Prepared in cooperation with the Missouri Department of Transportation
Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016
FLOW
Scientific Investigation Report 2017–5076
U.S. Department of the Interior U.S. Geological Survey Cover. Bathymetry and vertically averaged velocities of the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri, on May 25, 2016.
Back cover. Top: Point cloud visualization of the channel bed and right (west) side of main channel pier 11 of structure A6500 on Interstate 70 crossing the Mississippi River in St. Louis, Missouri, on May 25, 2016. Bottom: The U.S. Geological Survey boat surveying bathymetry and velocimetry at structures A4936 and A1850 on Interstate 255 crossing the Mississippi River near St. Louis, Missouri, on May 26, 2016. Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016
By Richard J. Huizinga
Prepared in cooperation with the Missouri Department of Transportation
Scientific Investigations Report 2017–5076
U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior RYAN K. ZINKE, Secretary U.S. Geological Survey William H. Werkheiser, Acting Director
U.S. Geological Survey, Reston, Virginia: 2017
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Suggested citation: Huizinga, R.J., 2017, Bathymetric and velocimetric surveys at highway bridges crossing the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016: U.S. Geological Survey Scientific Investigations Report 2017–5076, 102 p., https://doi.org/10.3133/sir20175076.
ISSN 2328-0328 (online) iii
Contents
Abstract...... 1 Introduction...... 1 Purpose and Scope...... 2 Description of Study Area...... 2 Description of Flow Conditions...... 2 Description of Equipment and Basic Processing...... 6 Basic Description of Methods...... 7 Surveying Methods...... 7 Survey Quality-Assurance/Quality-Control Measures...... 8 Beam Angle Check...... 8 Patch Tests...... 8 Uncertainty Estimation...... 10 Results of Bathymetric and Velocimetric Surveys...... 12 Structures A7577 and A4017 on U.S. Highway 40...... 13 Dual Bridge Structure A5585 on State Highway 364...... 24 Structures A3292 and L0561 on Interstate 70...... 32 Dual Bridge Structure A4557 on State Highway 370...... 40 Structure A3047 on U.S. Highway 67...... 48 Structure A6500 on Interstate 70...... 55 Structure A1500 on Interstate 55...... 63 Structures A4936 and A1850 on Interstate 255...... 69 General Findings and Implications...... 79 Effects of Low to Moderate Flooding Compared to Previous Surveys...... 79 Size and Shape of Scour Holes...... 82 Summary and Conclusions...... 88 References Cited...... 89 Appendix 1. Shaded Triangulated Irregular Network Images of the Channel and Side of Pier for Each Surveyed Pier...... 93 iv
Figures
1. Map showing location of surveyed bridges crossing the Missouri and Mississippi Rivers in the St. Louis, Missouri, metropolitan area...... 3 2. Graphs showing unit values of discharge from the streamflow-gaging stations on the Missouri River at St. Charles, Missouri, and on the Mississippi River at St. Louis, Missouri...... 5 3. Photographs showing the Teledyne RESON SeaBat® 7125-SV2 multibeam echosounder...... 7 4. Illustration showing generalized effects on data from a multibeam echosounder...... 9 5. Map showing total propagated uncertainty of bathymetric data from the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri...... 11 6. Map showing bathymetric survey of the Missouri River channel near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri...... 14 7. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri, on May 23, 2016, compared to previous surveys...... 15 8. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A7577 on U.S. Highway 40 crossing the Missouri River near St. Louis, Missouri...... 17 9. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A4017 on U.S. Highway 40 crossing the Missouri River near St. Louis, Missouri...... 18 10. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri, on May 23, 2016, and July 29, 2011...... 19 11. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri, on May 23, 2016, and October 18, 2010...... 22 12. Map showing bathymetry and vertically averaged velocities of the Missouri River channel near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri...... 23 13. Map showing bathymetric survey of the Missouri River channel near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri...... 25 14. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri, on May 24, 2016, compared to previous surveys...... 26 15. Profile showing key features, substructural and superstructural details, and surveyed channel bed along the upstream face of the upstream bridge of dual bridge structure A5585 on State Highway 364 crossing the Missouri River near St. Louis, Missouri...... 27 16. Profile showing key features, substructural and superstructural details, and surveyed channel bed along the upstream face of the downstream bridge of dual bridge structure A5585 on State Highway 364 crossing the Missouri River near St. Louis, Missouri...... 28 v
17. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri, on May 24, 2016, and August 1, 2011...... 29 18. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri, on May 24, 2016, and October 21, 2010...... 30 19. Map showing bathymetry and vertically averaged velocities of the Missouri River channel near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri...... 31 20. Map showing bathymetric survey of the Missouri River channel near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri...... 33 21. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri, on May 24, 2016, compared to previous surveys...... 34 22. Map showing bathymetry and vertically averaged velocities of the Missouri River channel near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri...... 35 23. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A3292 on Interstate 70 crossing the Missouri River near St. Louis, Missouri...... 36 24. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure L0561 on Interstate 70 crossing the Missouri River near St. Louis, Missouri...... 37 25. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri, on May 24, 2016, and August 2, 2011...... 38 26. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri, on May 24, 2016, and October 21, 2010...... 39 27. Map showing bathymetric survey of the Missouri River channel near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri...... 41 28. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri, on May 24, 2016, compared to previous surveys...... 42 29. Map showing bathymetry and vertically averaged velocities of the Missouri River channel near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri...... 43 30. Profile showing key features, substructural and superstructural details, and surveyed channel bed along the upstream face of the upstream bridge of dual bridge structure A4557 on State Highway 370 crossing the Missouri River near St. Louis, Missouri...... 44 31. Profile showing key features, substructural and superstructural details, and surveyed channel bed along the upstream face of the downstream bridge of dual bridge structure A4557 on State Highway 370 crossing the Missouri River near St. Louis, Missouri...... 45 32. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri, on May 24, 2016, and August 2, 2011...... 46 vi
33. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri, on May 24, 2016, and October 22, 2011...... 47 34. Map showing bathymetric survey of the Missouri River channel near structure A3047 on U.S. Highway 67 near St. Louis, Missouri...... 49 35. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near structure A3047 on U.S. Highway 67 near St. Louis, Missouri, on May 27, 2016, compared to previous surveys...... 50 36. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A3047 on U.S. Highway 67 crossing the Missouri River near St. Louis, Missouri...... 51 37. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near structure A3047 on U.S. Highway 67 near St. Louis, Missouri, on May 27, 2016, and August 3, 2011...... 52 38. Map showing difference between surfaces created from bathymetric surveys of the Missouri River channel near structure A3047 on U.S. Highway 67 near St. Louis, Missouri, on May 27, 2016, and October 25, 2010...... 53 39. Map showing bathymetry and vertically averaged velocities of the Missouri River channel near structure A3047 on U.S. Highway 67 near St. Louis, Missouri...... 54 40. Map showing bathymetric survey of the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri...... 56 41. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Mississippi River near structure A6500 on Interstate 70 in St. Louis, Missouri, on May 25, 2016, compared to previous surveys...... 57 42. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A6500 on Interstate 70 crossing the Mississippi River in St. Louis, Missouri...... 59 43. Point cloud visualization of the channel bed and right (west) side of main channel pier 11 of structure A6500 on Interstate 70 crossing the Mississippi River in St. Louis, Missouri...... 60 44. Map showing difference between surfaces created from bathymetric surveys of the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri, on May 25, 2016, and before construction, on July 7, 2009...... 61 45. Map showing bathymetry and vertically averaged velocities of the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri...... 62 46. Map showing bathymetric survey of the Mississippi River channel near structure A1500 on Interstate 55 in St. Louis, Missouri...... 64 47. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Mississippi River near structure A1500 on Interstate 55 in St. Louis, Missouri, on May 25, 2016, compared to previous surveys...... 65 48. Profile showing kKey features, substructural and superstructural details, and surveyed channel bed of structure A1500 on Interstate 55 crossing the Mississippi River in St. Louis, Missouri...... 66 49. Map showing difference between surfaces created from bathymetric surveys of the Mississippi River channel near structure A1500 on Interstate 55 in St. Louis, Missouri, on May 25, 2016, and October 20, 2010...... 67 50. Map showing bathymetry and vertically averaged velocities of the Mississippi River channel near structure A1500 on Interstate 55 in St. Louis, Missouri...... 68 51. Map showing bathymetric survey of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri...... 70 vii
52. Histogram showing frequency distribution of bed elevations for bathymetric survey-grid cells on the Mississippi River near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri, on May 26, 2016, compared to previous surveys...... 71 53. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A4936 on Interstate 255 crossing the Mississippi River near St. Louis, Missouri...... 72 54. Profile showing key features, substructural and superstructural details, and surveyed channel bed of structure A1850 on Interstate 255 crossing the Mississippi River near St. Louis, Missouri...... 73 55. Map showing bathymetry and vertically averaged velocities of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri...... 74 56. Map showing difference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri, on May 26, 2016, and October 19, 2010...... 76 57. Map showing difference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri, on May 26, 2016, and July 8, 2009...... 77 58. Map showing difference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri, on May 26, 2016, and May 12–13, 2009...... 78 59. Map showing difference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri, on May 26, 2016, and October 2–3, 2008...... 80 60. Graph showing average channel-bed and water-surface elevations near bridges on the Missouri and Mississippi Rivers near St. Louis, Missouri, from surveys in 2009, 2010, 2011, and 2016...... 82 61. Comparison of frequency distribution and cumulative percentage of bed elevations for bathymetric survey-grid cells from various surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri...... 83 62. Longitudinal profiles upstream from selected piers at structures A7577 and A4017 on U.S. Highway 40, and at dual bridge structure A5585 on State Highway 364, crossing the Missouri River near St. Louis, Missouri...... 85 63. Longitudinal profiles upstream from selected piers at structures A3292 and L0561 on Interstate 70, at dual bridge structure A4557 on State Highway 370, and at structure A3047 on U.S. Highway 67, crossing the Missouri River near St. Louis, Missouri...... 86 64. Longitudinal profiles upstream from selected piers at structure A6500 on Interstate 70, at structure A1500 on Interstate 55, and at structures A4936 and A1850 on Interstate 255, crossing the Mississippi River near St. Louis, Missouri...... 87 65. Longitudinal profiles upstream from railroad bridge piers near dual bridge structure A4557 on State Highway 370, and near structure A3047 on U.S. Highway 67, crossing the Missouri River near St. Louis, Missouri...... 88 viii
Appendix Figures
1–1. Shaded triangulated irregular network visualization of the channel bed and bents and piers of structures A7577 and A4017 on U.S. Highway 40 crossing the Missouri River near St. Louis, Missouri...... 94 1–2. Shaded triangulated irregular network visualization of the channel bed and piers of dual bridge structure A5585 on State Highway 364 crossing the Missouri River near St. Louis, Missouri...... 95 1–3. Shaded triangulated irregular network visualization of the channel bed and piers of structures A3292 and L0561 on Interstate 70 crossing the Missouri River near St. Louis, Missouri...... 96 1–4. Shaded triangulated irregular network visualization of the channel bed and piers of dual bridge structure A4557 on State Highway 370 crossing the Missouri River near St. Louis, Missouri...... 97 1–5. Shaded triangulated irregular network visualization of the channel bed and piers of structure A3047 on U.S. Highway 67 crossing the Missouri River near St. Louis, Missouri...... 98 1–6. Shaded triangulated irregular network visualization of the channel bed and piers of structure A6500 on Interstate 70 crossing the Mississippi River in St. Louis, Missouri...... 99 1–7. Shaded triangulated irregular network visualization of the channel bed piers of structure A1500 on Interstate 55 over the Mississippi River in St. Louis, Missouri...... 100 1–8. Shaded triangulated irregular network visualization of the channel bed and piers of structures A4936 and A1850 on Interstate 255 crossing the Mississippi River near St. Louis, Missouri...... 101 1–9. Shaded triangulated irregular network visualization of the channel bed and piers of structures A4936 and A1850 on Interstate 255 crossing the Mississippi River near St. Louis, Missouri...... 102
Tables
1. Highway bridges crossing the Missouri and Mississippi River in and into Missouri in the St. Louis metropolitan area, in downstream order...... 4 2. Results of a beam angle check from two check lines over a reference surface at the Lake of the Ozarks near Osage Beach, Missouri, on March 29, 2016...... 8 3. Patch test results at the Lake of the Ozarks near Osage Beach, Missouri, on March 29, 2016, and on the Missouri River in St. Louis, Missouri, on May 27, 2016...... 10 4. Total propagated uncertainty results for bathymetric data at a 1.64-foot grid spacing from surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016...... 10 5. Bridge and survey information, and selected channel-bed elevations from surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016...... 13 6. Results near piers and bents from surveys on the Missouri River near St. Louis, Missouri, May 23−27, 2016...... 16 7. Summary information and bathymetric surface difference statistics from surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri, from May 23–27, 2016, and previous surveys...... 20 8. Results near piers and bents from surveys on the Mississippi River near St. Louis, Missouri, May 23–27, 2016...... 58 ix
Conversion Factors
U.S. customary units to International System of Units
Multiply By To obtain Length foot (ft) 0.3048 meter (m) mile (mi) 1.609 kilometer (km) Volume cubic yard (yd3) 0.7646 cubic meter (m3) Flow rate foot per second (ft/s) 0.3048 meter per second (m/s) cubic foot per second (ft3/s) 0.02832 cubic meter per second (m3/s)
Datum
Vertical coordinate information is referenced to the North American Vertical Datum of 1988 (NAVD 88). Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).
Supplemental Information
In this report, the words “left” and “right” generally refer to directions that would be reported by an observer facing downstream. Distance on the Missouri River is given in river miles (RM) upstream from the confluence with the Mississippi River at St. Louis, Missouri, at river mile 195.2 of the Upper Mississippi River. Distance on the Mississippi River is given in river miles (RM) upstream from the confluence with the Ohio River at Cairo, Illinois, at river mile 953.5 of the Lower Mississippi River. Frequency is given in kilohertz (kHz). Data were collected, processed, and output in the International System of Units, and converted to U.S. customary units for presentation in the report at the request and for the convenience of the cooperator. x
Abbreviations
ADCP acoustic Doppler current profiler CUBE Combined Uncertainty Bathymetric Estimator GGA shorthand for the $GPGGA standard output format for Global Navigation Satellite System (GNSS) essential fix data defined by the National Marine Electronics Association (NMEA)-0183 standard that includes information on the three-dimensional location and accuracy of the GNSS receiver (National Marine Electronics Association, 2002) GNSS Global Navigation Satellite System IMU inertial measurement unit INS inertial navigation system MBES multibeam echosounder (the sonar system) MBMS multibeam echosounder mapping system (the sonar, navigation, and data acquisition system) MMS™ POS-Pac™ Mobile Mapping Suite (the navigation solution post-processing software) MoDOT Missouri Department of Transportation NMEA National Marine Electronics Association POS MV™ Position Orientation Solution for Marine Vessels (the inertial navigation system) RTK real-time kinematic (a type of differential correction for navigation with GNSS) RTN real-time network SBET smoothed best estimate of trajectory (a postprocessed navigation solution) TIN triangulated irregular network TPU total propagated uncertainty USGS U.S. Geological Survey VMT Velocity Mapping Toolbox (Parsons and others, 2013) Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016
By Richard J. Huizinga
Abstract Previous bathymetric surveys exist for all the sites exam- ined in this study. A previous survey in October 2010 at most of the sites had similar flow conditions and similar results to the Bathymetric and velocimetric data were collected by 2016 surveys. A survey during flood conditions in August 2011 the U.S. Geological Survey, in cooperation with the Missouri at the sites on the Missouri River and in May 2009 at structures Department of Transportation, near 13 bridges at 8 high- A4936 and A1850 (site 35) on the Mississippi River did not way crossings of the Missouri and Mississippi Rivers in the always indicate more substantial scour during flood condi- greater St. Louis, Missouri, area from May 23 to 27, 2016. A tions. At structure A6500 (site 33) on the Mississippi River, a multibeam echosounder mapping system was used to obtain previous survey in 2009 was part of a habitat assessment before channel-bed elevations for river reaches ranging from 1,640 to construction of the bridge and provides unique insight into the 1,970 feet longitudinally and extending laterally across the effects of the construction of that bridge on the channel in this active channel from bank to bank during low to moderate reach. Substantial scour was observed near the right pier, and flood flow conditions. These bathymetric surveys indicate the riprap blanket surrounding the left pier seems to limit scour the channel conditions at the time of the surveys and provide near that pier. Multiple additional surveys have been completed characteristics of scour holes that may be useful in the devel- at structures A4936 and A1850 (site 35) on the Mississippi opment of predictive guidelines or equations for scour holes. River, and the results of these surveys also are presented. These data also may be useful to the Missouri Department of Transportation as a low to moderate flood flow comparison to help assess the bridges for stability and integrity issues with respect to bridge scour during floods. Introduction Bathymetric data were collected around every pier that was in water, except those at the edge of water, and scour Scour in alluvial channels is the removal of channel bed holes were observed at most surveyed piers. The observed and bank material by flowing water and is the leading cause scour holes at the surveyed bridges were examined with of bridge failures in the United States (Richardson and Davis, respect to shape and depth. 2001). Scour at a bridge site is the result of short- and long- The frontal slope values determined for scour holes term geomorphic processes and the local effects caused by ele- observed in the current (2016) study generally are similar to ments of the structure in or adjacent to the waterway (Richard- recommended values in the literature and to values determined son and Davis, 2001; Huizinga and Rydlund, 2004). Because for scour holes in previous bathymetric surveys. Several of the effects of scour can be severe and dangerous, bridges and the structures had piers that were skewed to primary approach other structures over waterways are routinely assessed and flow, as indicated by the scour hole being longer on the side of inspected. Scour processes can be exacerbated during high- the pier with impinging flow, and some amount of deposition flow conditions because velocity and depth typically increase. on the leeward side, as typically has been observed at piers The Missouri Department of Transportation (MoDOT) is skewed to approach flow; however, at most skewed piers in the responsible for most of the transportation infrastructure in the State. current (2016) study, the scour hole was deeper on the leeward A part of this responsibility is fulfilled through periodic inspections of side of the pier. At most of these piers, the angled approach highway structures, including bridges that span waterways. At most flow was the result of a deflection or contraction of flow caused of these structures, all or most of the structure can be fully inspected by a spur dike near the pier, which may affect flow differently from land or from personnel lift trucks deployed from the roadway of than for a simple skew. At structure A6500 (site 33), the wide the structure; however, for structures over primary waterways, such face of the pier footing and seal course would behave as a com- as the Missouri and Mississippi Rivers, inspection of the part of the plex foundation, for which scour is computed differently. bridge that is underwater requires a different approach. 2 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
The U.S. Geological Survey (USGS), in cooperation bridges at 8 crossings in the greater St. Louis, Mo., metro- with MoDOT, began assessing scour at waterway crossings politan area (fig. 1) using a MBMS and an acoustic Doppler throughout the State in 1991 (Huizinga and Rydlund, 2004). In current profiler (ADCP; table 1). Equipment and methods 2007, the USGS, in cooperation with MoDOT, began deter- used and results obtained are described. The results obtained mining channel bathymetry and monitoring bridges for scour from the bathymetric and velocimetric surveys of the channel using single-beam echosounders and a multibeam echosounder document the channel-bed conditions and velocity distribution mapping system (MBMS; Rydlund, 2009; Huizinga, 2010, at the time of the surveys and provide characteristics of scour 2011, 2013, 2014, 2015, 2016; Huizinga and others, 2010). In holes that may be useful in developing predictive guidelines particular, the MBMS has proven to be a useful tool not only or equations for scour holes. These data also may be used by in determining channel bathymetry but also in providing a MoDOT as a low to moderate flood flow comparison to help medium- to high-resolution representation of bridge structural assess the bridges for stability and integrity issues with respect elements below the water line. In 2010, the USGS, in coopera- to bridge scour. Comparison of results to previous surveys at tion with MoDOT, began collecting bathymetric data at vari- the sites (Huizinga, 2011, 2012; Huizinga and others, 2010) ous highway bridges across primary waterways in Missouri. In also are provided. March 2010, 9 highway bridges at 7 crossings over the Mis- souri River near Kansas City, Missouri, were assessed using the MBMS (Huizinga, 2010); and in October 2010, 12 high- Description of Study Area way bridges at 7 crossings over the Missouri and Mississippi The study area for this report is the Missouri and Mis- Rivers near St. Louis, Mo., were assessed (Huizinga, 2011). sissippi Rivers in St. Louis, Mo., and includes the City of During high-flow conditions in June–August 2011, many of St. Louis, St. Louis County, and parts of St. Charles and the highway bridges and several of the railroad bridges along Jefferson Counties (fig. 1). The Missouri River flows through the entirety of the Missouri River downstream from Montana the St. Louis metropolitan area from west to east, joining the were assessed (Densmore and others, 2013; Dietsch and oth- Mississippi River north of downtown St. Louis. The Missouri ers, 2014), including the 37 highway bridges (at 28 crossings) and Mississippi Rivers are channelized in the St. Louis met- that span the Missouri River in and into Missouri (Huiz- ropolitan area; rock revetment, spur dikes, and L-head dikes inga, 2012). In April and May 2013, 10 highway bridges at are present along the banks to maintain the channel alignment, 9 crossings over the Missouri River between Kansas City and and levees and floodwalls are present on the upper banks to St. Louis, Mo., were assessed as part of more routine, non- limit flooding in the industrial, commercial, residential, and flood surveys at bridge sites in and into Missouri (Huizinga, agricultural areas on the flood plains. The site numbering 2014). In June 2014, eight highway bridges at seven crossings sequence used in previous studies on the Missouri and Missis- over the Missouri and Mississippi Rivers on the periphery of sippi Rivers (Huizinga, 2012, 2015) is used in this report for Missouri also were assessed as part of the routine, nonflood consistency and comparability. surveys at bridge sites (Huizinga, 2015). In June 2015, eight of the highway bridges at seven of the crossings near Kansas City were surveyed again (Huizinga, 2016). Description of Flow Conditions The current (2016) study is the second round of routine, nonflood surveys at the highway bridges across the Mis- Data from the streamflow-gaging station (hereinaf- souri and Mississippi Rivers near St. Louis, Mo. (fig. 1), ter referred to as “streamgage”) on the Missouri River at and includes 13 bridges at 8 crossings (table 1). One of the St. Charles, Mo. (station 06935965; U.S. Geological Survey, bridges at one crossing that was part of the previous surveys 2017; fig. 1), indicates the Missouri River was between flood in St. Louis (structure J1000 on U.S. Highway 40; Huizinga, rises when the sites on the Missouri River were surveyed on 2011, 2012) recently was replaced, resulting in structure May 23–27, 2016 (fig. 2A); however, the trough happened A4017 being made the westbound bridge and a new structure during generally higher late-spring flows (fig.B 2 ), during low A7577 being added as the new eastbound bridge (table 1); fur- to moderate flood flow conditions of nearly 150,000 cubic feet thermore, the new Stan Musial Veterans Memorial bridge on per second (ft3/s), compared to 60,000–65,000 ft3/s observed Interstate 70 (structure A6500; table 1) also is included in the during troughs in early April and late August. Similarly, data current study, the proposed location of which was the subject from the streamgage on the Mississippi River at St. Louis, Mo. of an aquatic habitat evaluation with MoDOT in 2009 before (station 07010000; U.S. Geological Survey, 2017; fig. 1), indi- construction (Huizinga and others, 2010). cates the Mississippi River also was between flood rises when the sites on the Mississippi River were surveyed May 25–26, 2016 (fig. 2A), but was during generally higher late-spring Purpose and Scope flows (fig. 2B). The discharge on the Missouri River as measured at The purpose of this report is to document the results of the St. Charles streamgage ranged from about 134,000 to bathymetric and velocimetric surveys completed in 2016 of 152,000 ft3/s during the dates of the surveys. This discharge the Missouri and Mississippi River channels near 13 highway range has a daily exceedance probability range of about 14 to Introduction 3
0 0 0 35 0 30 0 25 0 20 0 15 0 10
67
ILLINOIS 143 MISSOURI ILLINOIS3 67 A 278 MISSOURI est lar 94 27 Alton Bridge A30 7 Bellefontaine
Railroad Bridge 38 50 Florissant 79 370 67 26 ST. LOUIS COUNTY abash A08 0 Railroad A 557 East est 367 hain of Bridge Roc s 70 1 370 Bridge 94 Bridgeton St. Charles 270 ST. CHARLES COUNTY L0561 ld hain 25 of Roc s MADISON Bridge FLOW COUNTY 38 5 A32 2 170 367 70 94 A5585 East est 24 3 Maryland 67 eldon Heights Spring 364 A 017 23 D
340 340 40 61 64 CITY OF 70 38 0 A7577 270 170 ST. LOUIS 55 Merchants 141 MADISON Railroad 33 70 Bridge COUNTY A6500 Chesterfield 40 61 64 2 40 34 64 340 McKinley 61 A1500 64 Bridge 3 141 67 55 100 MISSOURI ILLINOIS 70 FLOW 100 44 38 35 100 A6500 33 30 255 ST. CLAIR 3 A 856 COUNTY Martin Luther King Bridge FLOW DOWNTOWN 55 ST. LOUIS 1412 Eads 30 270 64 Bridge 255 34 A 36 44 100 A1500 ST. CLAIR 38 30 21 Mehlville 35 COUNTY MacArthur30 61 A1850 Railroad 55 Bridge 67 MONROE Columbia 3 55 JEFFERSON COUNTY COUNTY 3 Base modified from U.S. Geological Survey digital data, 1:100,000, 1 6 0 1 2 3 5 MILES Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 1 2 3 5 KIL ME ERS
E PLANATION Principal railroad route
23 ILLINOIS Surveyed highway bridge location with site number— MISSOURI Numbering from Huizinga (2015) Kansas City, Mo. 1 U.S. Geological Survey streamflow-gaging station St. Louis, on the Missouri River at St. Charles, station 06935965 efferson City Mo. 2 U.S. Geological Survey streamflow-gaging station Osage Beach Cairo, Il. on the Mississippi River at St. Louis, station 07010000 Map area
Figure 1. Location of surveyed bridges crossing the Missouri and Mississippi Rivers in the St. Louis, Missouri, metropolitan area. 4 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO Figures . 1, 6–8, 10–12, 60–62, and appendix 1–1 1, 6–7, 9–12, 60–62, and appendix 1–1 1, 13–15, 17–19, 60–62, and appendix 1–2 1, 13–14, 16–19, 60–62, and appendix 1–2 1, 20–23, 25–26, 60–61, 63, and appendix 1–3 1, 20–22, 24–26, 60–61, 63, and appendix 1–3 1, 27–30, 32–33, 60–61, 63, and appendix 1–4 1, 27–29, 31–33, 60–61, 63, and appendix 1–4 1, 34–39, 60–61, 63, and appendix 1–5 1 1 1 1, 5, 40–45, 60–61, 64, and appendix 1–6 1 1 1, 46–50, 60–61, 64, and appendix 1–7 1, 51–53, 55–61, 64, and appendixes 1–8, 1–9 1, 51–52, 54–61, 64, and appendixes 1–8, 1–9 at river mile 195.2 of the Upper Mississippi — — — — — — — — Remarks Dual bridge crossing with A4017 Dual bridge crossing with A7577 Dual bridge crossing with Dual bridge crossing Dual bridge crossing Dual bridge crossing with L0561 A3292 Dual bridge crossing with Dual bridge crossing Dual bridge crossing A1850 Dual bridge crossing with A4936 Dual bridge crossing with No No No No No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Surveyed as part of this study a 8.1 43.9 32.7 29.6 27.0 202.6 190.8 182.6 181.2 180.2 180.0 179.2 168.8 mile River River Missouri Missouri Missouri Missouri Missouri Mississippi Mississippi Mississippi Mississippi Mississippi Mississippi Mississippi Mississippi , starting at the confluence with Mississippi River St. Louis, Mo. (fig. 1), Route US 40 E W US 40 MO 364 E W MO 364 IS 70 E W IS 70 MO 370 E W MO 370 US 67 US 67 IS 270 — IS 70 — — IS 55 IS 255 S IS 255 N County Mo. Mo. Mo. Mo. Mo. Mo. St. Charles, Mo. St. Louis, Mo. St. Charles, Mo. St. Louis, Mo. St. Charles, Mo. St. Louis, Mo. St. Charles, Mo. St. Louis, Mo. St. Charles, Mo. St. Charles, Mo. St. Louis City, St. Louis City, St. Louis City, St. Louis City, St. Louis City, St. Louis City, St. Louis, Mo. Local name Memorial Daniel Boone Daniel Boone Page Avenue Page Avenue Blanchette Blanchette Discovery Discovery Lewis & Clark Clark Chain of Rocks McKinley Veterans Stan Musial Martin Luther King Eads Poplar Street Barracks Jefferson Barracks Jefferson — — number Structure A7577 A4017 A5585 E W A5585 A3292 L0561 A4557 E W A4557 A3047 A4278 A0890 A6500 A4856 A1500 A4936 A1850 agency Primary Highway bridges crossing the Missouri and Mississippi River in into St. Louis metropolitan area, downstr eam order MoDOT MoDOT MoDOT MoDOT MoDOT IDOT IDOT IDOT MoDOT IDOT St. Louis MoDOT MoDOT
23 24 25 26 27 — — — 33 — — 34 35 Site For sites 23–27, river mile is the distance upstream on Lower Missouri River a (fig. 1) number Table 1. Table Illinois Department of westbound; MO, Missouri State highway; IS, Interstate —, not known/applicable; IDOT, W, US, U.S. highway; E, eastbound; Transportation; Missouri Department of [MoDOT, S, southbound; N, northbound; shaded rows are those bridges surveyed for this study] Transportation; starting at the confluence with Ohio River Cairo, Ill. (fig. 1), river mile 953.5 of Lower Mississippi River. For sites 33–35, river mile is the distance upstream on Upper Mississippi River, River. Introduction 5
450 A 425 E PLANATION 23 400 Approximate time of survey at indicated site number (fig. 1)
375
350 Mississippi River at 325 St. Louis, Missouri
300
33 34 35 275
250
225 Missouri River at 200 St. Charles, Missouri
175
27 150 23 24 26
125 25
100 5/15 5/17 5/19 5/21 5/23 5/25 5/27 5/29 5/31 6/2 6/4 500 B
400
Mississippi River at St. Louis, Missouri 300 Discharge, in thousand cubic feet per second
200
Missouri River at St. Charles, Missouri
100 Date range shown in 90 A above 80
70
60
50 4/1 4/16 5/1 5/16 6/1 6/16 7/1 7/16 8/1 8/16 9/1 Date
Figure 2. Unit values of discharge (1-hour interval) from the streamflow-gaging stations on the Missouri River at St. Charles, Missouri (station 06935965), and on the Mississippi River at St. Louis, Missouri (station 07010000; U.S. Geological Survey, 2017). A, May 15 through June 4, 2016. B, April 1 through September 1, 2016. 6 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
19 percent (based on flow duration analysis; U.S. Geological operated at a frequency of 400 kilohertz (kHz). The INS that Survey, 2003) and is less than the 50-percent annual exceed- was used is the Applanix Position Orientation Solution for ance probability (2-year recurrence interval) flood discharge Marine Vessels (POS MV™) WaveMaster system. The INS of 250,000 ft3/s (U.S. Army Corps of Engineers, 2003b, plate provides position in three-dimensional space and measures E–20). The discharge on the Mississippi River as measured the heave, pitch, roll, and heading of the vessel (and, thereby, at the St. Louis streamgage ranged from about 271,000 to the MBES) to accurately position the data received by the 290,000 ft3/s during the dates of the surveys. This discharge MBES. Real-time kinematic (RTK) differential corrections range has a daily exceedance probability range of about 20 to for the INS came from cellular communication with the 22 percent (based on flow duration analysis; U.S. Geological MoDOT Global Navigation Satellite System (GNSS) real- Survey, 2003) and is less than the 50-percent annual exceed- time network (RTN) for the navigation and tide solution dur- ance probability (2-year recurrence interval) flood discharge ing the 2016 surveys. of 450,000 ft3/s (U.S. Army Corps of Engineers, 2003a, As in previous surveys (Huizinga, 2010, 2011, 2012, table D–28). 2013, 2014, 2015, 2016), the navigation information from the Flow conditions at or less than the 50-percent annual 2016 surveys was postprocessed using the POS-Pac™ Mobile exceedance probability (2-year recurrence interval) flood are Mapping Suite (MMS™) software (Applanix Corporation, in the low to moderate flood-flow regime. In an analysis of 2009) to mitigate the effects of degraded positional accu- real-time scour monitor data at Jefferson City, Mo., Huizinga racy of the vessel while near or under a bridge. POS-Pac™ (2014) noted that substantial pier scour begins soon after MMS™ provides tools to identify and compensate for sensor the onset of hydrograph rise (substantial rise of 8 feet [ft] or and environmental errors and computes an optimally blended more), although the scour often does not reach maximum navigation solution from the GNSS and inertial measurement depth until the peak stage is reached or sometime thereafter unit (IMU) raw data. The blended navigation solution (called a (Huizinga, 2014, fig. 35). Although the peak discharge for the “smoothed best estimate of trajectory” or “SBET” file) gener- late spring happened shortly after the surveys, several moder- ated by postprocessing the navigation data was applied to the ate peaks had been observed at both streamgages, and flow survey at a given bridge to minimize the effects of the GNSS was substantially higher than base flow based on the daily outages while surveying under the bridges. exceedance values during the surveys (fig. 2B). Although the The data from the MBES and INS components were pro- scour scenario captured at the sites in this study may not rep- cessed and integrated into a cohesive dataset for cleanup and resent the maximum scour potential at the sites, the cumula- visualization. A computer onboard the survey vessel ran the tive information gathered at several sites during the course of HYPACK®/HYSWEEP® data acquisition software (HYPACK, multiple surveys in 2010, 2011, and 2016 remains useful for Inc., 2015) that was used to prepare for the bathymetric sur- determining scour for a variety of flow conditions, particu- veys and collect the survey data. After completing the surveys, larly when combined with, or compared to, a scour scenario the acquired depth data were further processed to remove data captured at high flood flow conditions. spikes and other spurious points in the multibeam swath trace, georeferenced using the navigation and position solution data from the SBET file from POS-Pac™ MMS™, and visualized Description of Equipment and Basic Processing in HYPACK®/HYSWEEP® as a triangulated irregular net- work (TIN) surface or a point cloud. The georeferenced data The bathymetry of the Missouri and Mississippi Rivers were output to a comma-delimited file, either having no data at each of the bridges was determined using a high-resolution reduction or filtered and reduced to a 1.64-ft data resolution. MBMS. The various components of the MBMS used for this These comma-delimited data were compiled into a geographic study are as described in reports about studies on the Missouri information system database for each site using the ArcGIS and Mississippi Rivers in Missouri (Huizinga, 2010, 2011, package (Esri, 2013), and are included with metadata in Huiz- 2012, 2013, 2014, 2015, 2016; Huizinga and others, 2010) inga (2017). and on the Missouri and Yellowstone Rivers in North Dakota Information about the velocity of the river at various (Densmore and others, 2013). The survey methods used to points throughout each study reach were collected using an obtain the data were similar to these previous studies, as were ADCP, similar to recent previous studies by Huizinga (2012, the measures used to ensure data quality. A brief description of 2013, 2014, 2015, 2016). A Teledyne RD Instruments Rio the equipment follows; a complete description of the various Grande ADCP operating at 600 kHz was used to obtain veloci- system components and methods used in this study is available ties at 1.64-ft increments, or “bins,” throughout the water in the previous reports by Huizinga (2010), Huizinga and oth- column. The Rio Grande 600 kHz ADCP operates in depths ers (2010), and Densmore and others (2013). from 2.3 to 230 ft and determines the velocity of the water A MBMS is an integration of several individual com- by measuring the Doppler shift of an acoustic signal reflected ponents: the multibeam echosounder (MBES), an inertial from various particles suspended in the water (Mueller and navigation system (INS), and a data-collection and data- others, 2013). By measuring the Doppler shift in four different processing computer. The MBES that was used for the 2016 beam directions, the velocity of the water in each bin can be surveys is the Teledyne RESON SeaBat® 7125-SV2 (fig. 3), determined in three dimensions. Introduction 7
A B
Piezo- ceramic Piezoceramic receiver projector array Stabilizer array struts
Sound velocity probe (inside shroud) Head tilt bracket
Transducer head
Figure 3. The Teledyne RESON SeaBat® 7125-SV2 multibeam echosounder. A, viewed from the bottom. B, mounted on the port side of the U.S. Geological Survey boat.
Basic Description of Methods and moored barges made surveying difficult in some areas. Areas near the bridge piers and along the banks also were The methods used to acquire and ensure the collection of surveyed in an upstream direction with the MBES head tilted quality data were the same as those used in previous studies at either 30 degrees to port or starboard to increase the acquisi- using the MBES (methods are detailed in Huizinga, 2010, tion of bathymetric data in the shallow areas, and higher on 2012; Huizinga and others, 2010). A brief summary of—and the banks and the sides of the piers. To limit potential damage differences from—these methods are highlighted below. to the MBES head, most of the shallow areas (less than about 6 ft of water depth) were not surveyed. Surveying Methods After completing the bathymetric survey with the MBMS at a given site, the velocity data were obtained with the ADCP Generally, the surveyed area extended across the active on seven lateral sections across the channel within the study channel from bank to bank, as had been done in the previous area. The position and speed of the boat was determined using studies on the Missouri and Mississippi Rivers near St. Louis a differential GNSS receiver mounted on a pole directly above (Huizinga, 2011, 2012). The surveyed reaches ranged from the ADCP. The bottom-track reference method for determining 1,640 to 1,970 ft long in the direction of flow, positioned so boat speed was anticipated to be unusable because of moving that the surveyed highway bridges were about one-third to channel-bed material, so the boat velocity was determined using one-half of the total length from the upstream boundary, using the GNSS essential fix (GGA) National Marine Electronics about the same upstream and downstream boundaries as were Association (NMEA)–0183 sentence (National Marine Elec- used in the 2011 flood study (Huizinga, 2012). The upstream tronics Association, 2002) from the differential GNSS receiver. and downstream boundaries of the surveyed areas were The distance between the velocity section lines generally was assumed to be beyond the substantial hydraulic effects (wake about 260 ft. Three sections were upstream and four sections vortices and shear flow) of the bridge structures. were downstream from the bridge in question. Each section line As in previous studies, bathymetric data were obtained was traversed in each direction across the river. The reported along longitudinal transect lines, and each survey was velocity values are the average from the two traverses of a given designed so that there was overlap of the survey swaths to section line, using averaging algorithms from the Velocity Map- attempt to ensure complete coverage of the channel bed and ping Toolbox (VMT; Parsons and others, 2013). Discharge for a minimize sonic “shadows.” Substantial overlap was achieved site was computed as the average of the discharges from recip- for many of the surveyed swaths, except in shallow areas near rocal pairs (two transects per section line) at the various sections the channel banks or spur dikes, and near in-flow structures, in the reach. Generally, measured discharge for an individual debris rafts, or moored barges. The presence of debris rafts transect was within 5 percent of the average. 8 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Survey Quality-Assurance/Quality-Control Table 2. Results of a beam angle check from two check lines Measures over a reference surface at the Lake of the Ozarks near Osage Beach, Missouri, on March 29, 2016.
A quality-assurance plan has been established for discharge [<, less than; —, no data] measurements using ADCPs that includes several instrument diagnostic checks and calibrations. These standard operating pro- Beam Maximum Mean Standard 95-percent cedures were followed when acquiring the velocity profile data angle limit outlier difference deviation confidence for these surveys, including a moving-bed test. For a detailed (degree) (foot) (foot) (foot) (foot) discussion of these procedures, see Mueller and others (2013). 0 0.46 –0.07 0.10 0.16 For the MBMS, the principal quality-assurance measures 5 0.52 –0.07 0.10 0.16 were assessed in real time during the survey. The MBMS operator continuously assessed the quality of the collected 10 0.39 –0.07 0.10 0.16 data during the survey by making visual observations of 15 0.33 –0.07 0.10 0.16 across-track swaths (such as convex, concave, or skewed bed 20 0.49 –0.03 0.10 0.20 returns in flat, smooth bottoms), noting data quality flags and 25 0.62 –0.03 0.10 0.16 alarms from the MBES and the INS, and noting comparisons 30 0.66 –0.03 0.10 0.20 between adjacent overlapping swaths. In addition to the real- time quality-assurance assessments during the survey, beam 35 0.75 –0.03 0.10 0.20 angle checks and a suite of patch tests were executed to ensure 40 0.69 –0.03 0.13 0.23 quality data were acquired from the MBMS before the 2016 45 0.89 –0.03 0.13 0.30 surveys. These tests were completed at the Lake of the Ozarks 50 1.05 0.00 0.20 0.36 near Osage Beach, Mo. (fig. 1, index map). Additional patch 55 1.54 0.07 0.23 0.49 tests were completed on the last day of the 2016 surveys, on 60 1.71 0.16 0.36 0.72 the Missouri River near St. Louis, to check that the mounting angles had not moved during the surveys. 65 2.13 0.16 0.33 0.66 Performance standardsa Beam Angle Check 1.00 <0.20 — <0.80 Met, angle <50 Met — Met A beam angle check is used to determine the accuracy of the depth readings obtained by the outer beams (greater than aPerformance standard check values are from U.S. Army Corps of Engineers 25 degrees from nadir [vertical]) of the MBES (U.S. Army (2013, table 3–1). Corps of Engineers, 2013), which may change with time as a was expected to be greater than the average depth observed result of inaccurate sound velocities, physical configuration in the 2016 surveys because the average depths observed dur- changes, and overall depth being surveyed. The HYPACK®/ ing the previous surveys in the St. Louis area generally were HYSWEEP® software has a utility that develops a statistical less than 40 ft (the average depth is the difference between assessment of the quality of the outer beams compared to a the average water surface elevation and average channel-bed reference surface (HYPACK, Inc., 2015). On March 29, 2016, elevation in Huizinga [2012, table 5]). As described earlier a reference surface was surveyed for a part of the Lake of the in the “Surveying Methods” section in this report, areas with Ozarks near Osage Beach (fig. 1, index map), and check lines depths greater than the average depths generally had substan- were run across the reference surface. Included with the mea- tial overlap of the surveyed swath with adjacent swaths. Data surement was a sound-velocity profile cast to document and from the outer beams in these areas were able to be either quantify any stratification in the water column near the refer- verified or removed to mitigate any detrimental effects caused ence surface. The results of this beam angle check (table 2) by beam angle inaccuracies. were within the recommended performance standards used by the U.S. Army Corps of Engineers for hydrographic surveys Patch Tests for all the representative angles below 50 degrees (U.S. Army Corps of Engineers, 2013), permitting the use of the central Patch tests are a series of dynamic calibration tests that are 90 degrees of the sound navigation and ranging (sonar) swath used to check for subtle variations in the orientation and timing with confidence. of the MBES with respect to the INS and real-world coor- Ideally, the average depth of the reference surface used dinates. The patch tests are used to determine timing offsets in the beam angle check would be equal to or greater than caused by latency between the MBES and the INS, and angular the depth in the area being surveyed. The depth of the Mis- offsets to roll, pitch, and yaw caused by the alignment of the souri and Mississippi Rivers in each study reach generally transducer head (fig. 4). These offsets have been observed to was impossible to estimate before each survey because of the be essentially constant for a given survey, barring an event that dynamic nature of the channel bed and flow conditions; how- causes the mount to change such as striking a floating or sub- ever, the average depth of the reference surface (about 53 ft) merged object (Huizinga, 2010, 2011, 2012, 2014, 2015, 2016). Introduction 9
∆t A. Latency B. Roll
α
α
C. Pitch D. aw
β δ
δ β
E PLANATION Actual bottom Measured bottom ∆t Timing offset for latency between the multibeam echosounder and Global Navigation Satellite System components of the inertial navigation system α Angular offset for roll of the transducer head along the longitudinal axis of the boat β Angular offset for pitch of the transducer head along the lateral axis of the boat δ Angular offset for yaw of the transducer head about the vertical axis
Figure 4. Generalized effects on data from a multibeam echosounder. A, timing offset for latency. B, angular offset for roll. C, angular offset for pitch. D, angular offset for yaw.
The offsets determined in the patch test are applied when 30 degrees to port tilt. The measured offset angles for processing the data collected during a given survey. roll, pitch, and yaw are somewhat different from previ- Patch tests were completed before the 2016 surveys at ous surveys with this equipment (Huizinga, 2016, table 3), the Lake of the Ozarks near Osage Beach, Mo. (fig. 1, index and likely is the result of adjustments made to the mount map), and again on the last day of surveying, while at site 27 between mobilization for the 2015 and 2016 surveys. It (structure A3047 on U.S. Highway 67; fig. 1) over the Mis- was noted in Huizinga (2010) that a sensitivity analysis of souri River near St. Louis (table 3). Although the MBES had the four offsets implied that the ultimate position of sur- several minor strikes of floating debris at various times during veyed points in three-dimensional space was least sensitive the 2016 surveys, there were no apparent changes to the roll, to the angular offset for yaw, whereas it was most sensitive pitch, or yaw angles from the beginning to the end of the to the angular offset for roll. surveys (table 3). The bathymetric data were processed to apply the offsets For this study, there was no measured timing offset determined from the patch tests, and to remove data spikes (table 3; Δt=0, fig. 4), which is consistent with latency and other spurious points in the multibeam swaths through test results for this boat and similar equipment configura- the use of automatic filters and manual editing. The bathymet- tion used in other surveys (Huizinga, 2010, 2011, 2012, ric data were then projected to a three-dimensional grid at a 2013, 2014, 2015, 2016; Huizinga and others, 2010). The resolution of 1.64 ft using the Combined Uncertainty Bathy- measured angular offset for pitch and yaw for all head- metric Estimator (CUBE) method (Calder and Mayer, 2003), tilt configurations remained constant at –1.00 degree and as implemented in the MB–MAX processing package of the 1.00 degree, respectively, for both patch tests (table 3). The HYPACK®/HYSWEEP® software (HYPACK, Inc., 2015) and measured angular offset for roll also remained constant used to generate a gridded raster surface of the channel bed for both patch tests for the various head tilt configurations near each bridge (hereinafter referred to as a “bathymetric (table 3) with –2.35 degrees for no tilt, –32.45 degrees surface”) using ArcGIS. The bathymetric surface for each site for 30 degrees to starboard tilt, and 27.75 degrees for from the 2016 survey was compared to similar bathymetric 10 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Table 3. Patch test results at the Lake of the Ozarks near Osage Beach, Missouri, on March 29, 2016, and on the Missouri River in St. Louis, Missouri, on May 27, 2016.
[sec, second; deg, degree]
Timing Angular Angular offset Angular offset Date of offset offset for roll for pitch for yaw Head tilt test (sec) (deg) (deg) (deg) 03/29/16 0 –2.35 –1.00 1.00 None. 05/27/16 0 –2.35 –1.00 1.00 None. 03/29/16 0 –32.45 –1.00 1.00 30 degrees starboard. 05/27/16 0 –32.45 –1.00 1.00 30 degrees starboard. 03/29/16 0 27.75 –1.00 1.00 30 degrees port. 05/27/16 0 27.75 –1.00 1.00 30 degrees port. surfaces created from previous surveys at a bridge by taking which provides a robust estimate of the spatial distribution of the difference between the 2016 raster surface and the previ- possible uncertainty within the survey area (Czuba and others, ous survey raster surface. Statistics of the elevations for each 2011); thus, the TPU of a point is a measure of the accuracy bathymetric surface were determined, as were statistics of the to be expected for such a point when all relevant error sources differences between the surfaces. Sediment volumes for cut are taken into account (Czuba and others, 2011). Statistics of (scour) and fill (deposition) between the 2016 survey and pre- TPU for each of the survey areas are shown in table 4, and an vious surveys in 2009, 2010 and 2011 also were determined example of the spatial distribution of TPU typically observed in from differences in the raster surfaces using ArcGIS. the survey data is shown in figure 5 for the bathymetric data at structure A6500 on Interstate 70 over the Mississippi River. The largest TPU in this group of surveys was about Uncertainty Estimation 2.53 ft (table 4); however, as noted in previous studies, TPU values of this magnitude typically happened near high-relief Similar to the previous studies of bathymetry in Mis- features, such as the front or side of a pier footing (fig. 5). souri (Huizinga, 2010, 2011, 2012, 2013, 2014, 2015, 2016), Most of the TPU values (more than 97 percent) were less than uncertainty in the surveys was estimated by computing the 0.50 ft (table 4), which is within the specifications for a “Spe- total propagated uncertainty (TPU) for each survey-grid cell in cial Order” survey, the most-stringent survey standard of the the bathymetric surface of each survey area, using the CUBE International Hydrographic Organization (IHO; International method (Calder and Mayer, 2003) as implemented in the MB- Hydrographic Organization, 2008). The TPU values were MAX processing package of the HYPACK®/HYSWEEP® soft- larger near moderate-relief features (banks, spur dikes, rock ware (HYPACK, Inc., 2015). The CUBE method allows all ran- riprap and outcrops, and scour holes near piers; fig. 5). Occa- dom system component uncertainties and resolution effects to sionally, the TPU values also were larger (1.00 ft or greater) be combined and propagated through the data processing steps, in the outermost beam extents of the multibeam swath in the Table 4. Total propagated uncertainty results for bathymetric data at a 1.64-foot grid spacing from surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016.
[MoDOT, Missouri Department of Transportation; ft, foot]
Maximum Mean Standard Percentage of bathymetry points with Site MoDOT Median value value of value of deviation of uncertainty value less than number structure of uncertainty uncertainty uncertainty uncertainty (fig. 1) number (ft) (ft) (ft) (ft) 2.00 ft 1.00 ft 0.50 ft 0.25 ft 23 A7577/A4017 1.38 0.17 0.13 0.12 100.0 99.8 97.2 90.9 24 A5585 E & W 1.71 0.15 0.13 0.11 100.0 99.9 97.9 92.3 25 A3292/L0561 1.54 0.16 0.13 0.13 100.0 99.7 97.0 87.1 26 A4557 E & W 1.44 0.14 0.13 0.09 100.0 99.9 98.7 93.1 27 A3047 1.38 0.15 0.13 0.11 100.0 99.9 97.9 92.8 33 A6500 2.00 0.21 0.20 0.08 100.0 99.9 99.1 78.7 34 A1500 2.53 0.20 0.20 0.09 100.0 99.9 98.5 89.0 35 A4936/A1850 1.71 0.19 0.20 0.08 100.0 99.9 99.0 89.6 Introduction 11
1.50+ 1.25 1.00 0.75 0.50 0.25 0 $
E PLANATION
Total propagated Total uncertainty of channel-bed elevation, in feet 90°10'20"
May 25, 2016 90°10'25"
396.6 feet above the NAVD 88 396.6 feet above the NAVD 276,000 cubic feet per second 90°10'30"
Survey date Discharge elevation water-surface Average
Stone revetment Stone Stone revetment Stone Stone revetment Stone
barge 90°10'35" Sunken
Pier 11 Riprap blanket Riprap Moored barge Moored
Mooring dolphins 90°10'40" FEET METERS 500 150 400 100 300
FLOW 200 90°10'45" 50 100
0 0 90°10'50"
Pier 10
Moored barge
dolphin
Mooring
Mooring dolphins
dolphin Moored dock
Mooring Moored barge Moored
Moored barge Moored Moored barge
Stone revetment Stone 90°10'55"
Stone revetment Stone Stone revetment 90°11' otal propagated uncertainty of bathymetric data from the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, T
.
90°11'05" Figure 5. Missouri Base from ational Agriculture Imagery Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American atum of 1 88 A 88
38°38'50" 38°38'45" 38°38'40" 38°38'35" 12 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO overlap with an adjacent swath, particularly when the MBES Previous bathymetric surveys have happened at all the head was tilted for the survey lines along the banks or near bridge sites in this study (Huizinga, 2010, 2012; Huizinga and the piers (fig. 5). Overlapping adjacent swaths in the channel others, 2010); furthermore, several of the sites had a Level II thalweg (the line of maximum depth in the channel) also can bridge scour assessment (Lagasse and others, 1991; Huizinga display larger TPU values because substantial bed movement and Rydlund, 2004). A map showing the difference in channel- can happen between survey passes (fig. 5). More than three- bed elevation for the area common to each surveys is included quarters (78 percent or more) of the channel bed at the sites for each site, and data from previous surveys are included in had TPU values of 0.25 ft or less (table 4). The tops of bridge the cross-section plot for that bridge. The difference maps substructural elements (pier footings and seal courses) typi- were created by taking the difference between the 2016 raster cally had TPU values of 0.25 ft or less. surface and a previous survey raster surface at a given bridge, The survey at structure A6500 on Interstate 70 had the and summary statistics (maximum, minimum, and mean) highest mean value of TPU, as well as generally the lowest of the difference rasters were determined. The surveys are percentage of bathymetry points that were less than the various broadly compared based on their timing and the discharge at TPU value cutoffs (table 4). There were a few impediments the time of the survey. If a site was subject to a Level II assess- to surveying at this site in the form of mooring dolphins and ment, the cross section of the channel on the downstream moored barges along both banks, but otherwise the survey was side of the bridge obtained during the Level II assessment is obtained with relatively smooth longitudinal swathes (fig. 5), included on the cross-section plot for that bridge. which was the case at nearly all the sites surveyed in this study. Although the configuration of the channel bed and the The primary anomaly at this site was near a series of moored underlying sediment transport conditions at a given site are barges along the right bank (“left” and “right” refer to directions associated with an instantaneous discharge in the discussions that would be reported by an observer facing downstream), that follow, a given bathymetric surface actually is a reflec- where objects on the channel bed and limited coverage resulted tion of more than those instantaneous transport conditions. A in substantial TPU values (fig. 5). Substantial TPU values also wide variety of factors affect the channel-bed configuration were observed near the piers because of the vertical sides of the of a reach for a given discharge (Gilbert and Murphy, 1914), footings and seal courses (fig. 5). Generally, the magnitude and including flow velocities and velocity distribution, the size distribution of TPU values observed at this site are representa- and timing of previous flood rises, whether or not the stage tive of those observed at all the other surveyed sites. currently is rising or falling, and other local hydraulic condi- tions; furthermore, the channel-bed configuration at a site is affected by upstream and local sediment conditions and contributions, as well as water temperature and other seasonal Results of Bathymetric and variations. Because of the myriad number and interactions Velocimetric Surveys of factors affecting sediment transport conditions and the resultant bed configuration, it would be simplistic to assume The site-specific results for each bridge are discussed in that the configuration and size of bed forms observed during the following sections, starting with the upstream-most bridge the current (2016) surveys near St. Louis are dependent only site on the Missouri River and progressing downstream along upon the instantaneous discharge at a given site. Although it the Mississippi River. The site-specific results are followed by a is beyond the scope of the current (2016) study to examine all discussion of general findings that are not specific to a particular the antecedent conditions that created the observed channel- site. The range of bed elevations described as “the channel-bed bed configuration, the comparisons with previous surveys elevations” for each survey was based on statistical analysis of under different flow conditions nevertheless contribute to the gridded raster surface of the bathymetry data at each site, understanding the many complexities of sediment transport. and covers the percentile range from 5 to 95 percent of the data. As in recent previous studies (Huizinga, 2012, 2013, Because the surveys generally were limited to the active chan- 2014, 2015, 2016), when discussing the vertically averaged nel from bank to bank excluding overbank areas, this percentile velocity values obtained during the surveys in the sections that range generally covered the channel bed but excluded the banks follow, neighboring vectors having random variations in direc- and localized high or low spots, such as spur dikes or scour tion and magnitude were taken as an indication of nonuniform holes near piers. All elevation data were referenced to the North flow in the section resulting from shear and wake vortices. American Vertical Datum of 1988 (NAVD 88). Conversely, neighboring vectors having gradual and system- For consistency with earlier studies, dune sizes are atic variations were taken as an indication of uniform flow in described in general terms for each of the bridge sites using the section. The velocity data for each section are an average the categories set by Huizinga (2012) for the discussion of of two velocity transects, spatially averaged to the section line bathymetry during the 2011 flood. In this report, small dunes using algorithms in the Velocity Mapping Toolbox (Parsons and ripples are those that are less than 5 ft high from crest to and others, 2013). trough, medium dunes are those that are 5 to 10 ft high, large Shaded TIN images of the channel and side of pier were dunes are those that are 10 to 15 ft high, and very large dunes prepared for each surveyed pier. These visualizations are are those that are 15 ft or more in height. shown in appendix figures 1–1 to 1–9. Results of Bathymetric and Velocimetric Surveys 13
Structures A7577 and A4017 on U.S. Highway 40 dunes was present in the middle of the channel, and numerous other small dunes and ripples were present throughout the rest Structures A7577 and A4017 (site 23) are dual bridges of the channel (fig. 6). As in previous surveys (Huizinga, 2011, on U.S. Highway 40, crossing the Missouri River at river mile 2012), a rock outcrop and a longitudinal spur dike were pres- (RM) 43.9, on the northwestern side of the St. Louis metro- ent on the left (north) bank downstream from the bridges, and politan area between Chesterfield and Weldon Spring, Mo. several other spur dikes were present on both banks (fig. 6). (fig. 1). The site was surveyed on May 23, 2016, and the aver- A construction causeway had been built into the channel from age water-surface elevation near the bridge, determined by the the left bank upstream from structure A7577 and the spur dike RTK GNSS tide solution, was 446.0 ft (table 5). Discharge on on the left bank under structure A4017 (fig. 6). Remnants of the Missouri River was about 117,000 ft3/s during the survey piers from old downstream structure J1000 are evident down- (table 5). stream from the spur dike on the left bank and downstream The survey area was about 1,840 ft long and about from pier 5 of downstream structure A4017 (fig. 6). 1,480 ft wide, extending across the active channel from bank Near the piers near the left bank (structure A7577 bents 6 to bank (fig. 6). The upstream end of the survey area was and 7, and structure A4017 pier 4, fig. 6), a localized deep about 620 ft upstream from the centerline of structures A7577 scour hole near the end of the construction causeway upstream and A4017 (fig. 6). The channel-bed elevations ranged from from the spur dike had an approximate minimum channel-bed about 413 to 435 ft for most of the surveyed area (5th to elevation of about 410 ft (table 6); however, bent 6 of structure 95th percentile range of the bathymetric data; table 5; fig. 7), A7577 and pier 4 of structure A4017 essentially were embed- except near the main channel piers of structures A7577 and ded in the rock of the construction causeway and spur dike on A4017 and near the ends of or downstream from various the left bank (fig. 6), which will limit or prevent scour near spur dikes (fig. 6). The thalweg was not well defined in the these piers. Near bent 7 of upstream structure A7577, a local upstream channel, but seemed to develop downstream from scour hole had an approximate minimum channel-bed eleva- the bridges, and was about 8 ft deeper than the channel bed in tion of about 406 ft (table 6), about 5 ft above the approximate the middle of the channel (fig. 6). A series of small to medium minimum channel-bed elevation of 401 ft (table 5), and about Table 5. Bridge and survey information, and selected channel-bed elevations from surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri, May 23–27, 2016.
[MoDOT, Missouri Department of Transportation; ADCP, acoustic Doppler current profiler; ft3/s, cubic foot per second; ft, foot; US, U.S. highway; E, east- bound; W, west-bound; MO, State highway; IS, Interstate highway; all elevations are in feet above the North American Vertical Datum of 1988]
Discharge Average Approximate channel-bed Approximate Average Site MoDOT from ADCP water-surface elevation of the indicated per- minimum Survey River channel-bed number structure Route measure- elevation near centile of the bathymetric data channel-bed date milea elevationc (fig. 1) number mentsb the bridge elevationd (ft) 5th percentile 95th percentile (ft3/s) (ft) (ft) (ft) (ft) 23 A7577/A4017 05/23/16 US 40 43.9 117,000 446.0 423.1 412.7 434.7 401 24 A5585 E & W 05/24/16 MO 364 32.7 110,000 434.1 414.4 406.0 424.1 399 25 A3292/L0561 05/24/16 IS 70 29.6 116,000 431.8 412.2 403.6 422.8 389 26 A4557 E & W 05/24/16 MO 370 27.0 114,000 429.9 408.0 399.0 416.8 388 27 A3047 05/27/16 US 67 8.1 131,000 413.7 392.1 381.3 403.0 374 33 A6500 05/25/16 IS 70 181.2 276,000 396.6 362.2 353.5 382.5 334 34 A1500 05/25/16 IS 55 179.2 279,000 395.7 360.5 350.0 382.0 340 35 A4936/A1850 05/26/16 IS 255 168.8 290,000 390.5 359.7 350.1 375.3 322 aFor sites 23–27, river mile is the distance upstream on the Lower Missouri River, starting at the confluence with the Mississippi River at St. Louis, Mo. (fig. 1), at river mile 195.2 of the Upper Mississippi River. For sites 33–35, river mile is the distance upstream on the Upper Mississippi River, starting at the confluence with the Ohio River at Cairo, Ill. (fig. 1), at river mile 953.5 of the Lower Mississippi River. bThe average discharge obtained while making the various velocity transects. The reported value is the discharges computed using Global Navigation Satel- lite System (GNSS) essential fix GGA data string as the reference, as described in the “Surveying Methods” section of the text. cThe statistical average of the gridded raster surface of channel-bed elevations. dThe minimum channel-bed elevation of the gridded raster surface, not necessarily in any scour holes near the bridge.
Structures A7577 and A4017 on U.S. Highway 40. 14 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
38 1 25
0 0 05 0 0 00 0 3 55 0 3 50 0 3 5 0 3 0 0 3 35 0 3 30 0 3 25 38 1 20 A B E PLANATION Channel-bed elevation, in feet above the North American
Construction causeway Vertical Datum of 1988 450
445 Rock Spur dike Longitudinal spur dike outcrop 0 0 05 440
Remnant 435 of J1000 A7577 Pier 4 38 1 15 Bent 6 A4017 430 Pier 4 425 Small dunes and ripples c-c' Medium dunes 420 A7577 Bent 7 415
410
Longitudinal sections 405 shown in figure 62 Remnant of J1000 f-f' Pier 5 400 d-d' A4017 38 1 10 FLOW Pier 5 A7577 395 Bent 8 Medium dunes No data Small dunes and ripples
Spur dike
g-g' e-e' A4017 38 1 05 A7577 Pier 6 $ Bent 9
Survey date May 23, 2016
Spur dike B'Cross section shown Discharge 117,000 cubic feet per second A' in figure 9 Cross section shown Average water-surface elevation 0 0 00 in figure 8 446.0 feet above the NAVD 88
Base from ational Agricultural Information Program, 201 0 100 200 300 400 500 FEET Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 METERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88 0 3 20
Figure 6. Bathymetric survey of the Missouri River channel near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 15
2.25 100
E PLANATION 2.00 90 [ft3/s, cubic foot per second] Frequency distribution 80 1.75 2016 survey data; 117,000 ft3/s 70 2011 survey data; 1.50 220,000 ft3/s 2010 survey data; 60 3 1.25 95,300 ft /s Cumulative percentage 50 2016 survey data; 1.00 117,000 ft3/s 40 2011 survey data; 3 0.75 220,000 ft /s
lower thanindicated elevation 2010 survey data; 30 3
Percentage of total survey-grid cells 95,300 ft /s
0.50 Cumulative percentage of survey-grid cells 20
0.25 10
0 0 395 400 405 410 415 420 425 430 435 440 445 450 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 7. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri, on May 23, 2016, compared to previous surveys.
9 ft below the average channel bed immediately upstream old structure J1000, where a scour hole present in the 2011 from the bent (the “Depth of scour hole from upstream chan- survey (Huizinga, 2012) has subsequently been filled (fig. 10). nel bed,” table 6; fig. 6). A local scour hole near pier 5 of The mean difference between the bathymetric surfaces (the downstream structure A4017 had a minimum elevation of statistical mean value of the gridded raster surface [fig. 10] 412 ft, about 11 ft below the average channel bed immediately created from the difference between the 2016 and 2011 upstream from the pier, and slightly deeper than the approxi- [previous] survey gridded raster bathymetric surfaces) was mate minimum elevation of the local scour hole near bent 8 of –0.27 ft (table 7), indicating overall minor channel degrada- upstream structure A7577 of 415 ft (fig. 6; table 6). tion between the 2011 and 2016 surveys. The net volume of Information from bridge plans indicate that all the bents cut in the reach from 2011 to 2016 was about 144,300 cubic of structure A7577 are shafts drilled 15 to 16 ft into bed- yards (yd3), and the net volume of fill was about 117,700 yd3, rock, with about 20 ft of bed material between the bottom of resulting in a net loss of about 26,700 yd3 of sediment between the scour hole and bedrock at bent 7 (fig. 8; table 6), which 2011 and 2016. The cross sections from the two surveys along increases substantially to the right (south) because of the the upstream face of the upstream structure A7577 bridge are sloping bedrock in the area (fig. 8; table 6). Information from not substantially different from one another between bents 7 bridge plans indicate that pier 4 of structure 4017 is a footing and 9 except near the new bents, but the scouring effect of the founded on bedrock, and about 15 ft of bed material was pres- construction causeway is clearly evident between bents 6 and ent between the bottom of the scour hole and bedrock (fig. 9; 7 (fig. 8). The frequency distribution of bed elevations also table 6). Piers 5 and 6 of structure A4017 are founded on was not substantially different in shape in 2016 than in 2011, shafts drilled 13 to 26 ft into bedrock, and more than 44 ft of except without the higher percentage of survey-grid cells with bed material was present between the bottom of the scour hole elevations between 420 and 426 ft evident in the 2011 and and bedrock (fig. 9; table 6) because of the sloping bedrock in 2010 surveys, and without the spike of grid cells with eleva- the area (fig. 9; table 6). tions around 436 ft evident in 2011 (fig. 7). A large mound The difference between the survey on May 23, 2016, and of rock near bent 9 of upstream structure A7577 (fig. 8) also the previous flood survey on July 29, 2011, does not indicate had been removed, which resulted in an area of substantial substantial bed variation from 2011 to 2016, with the excep- scour indicated near that bent and deposition around pier 6 of tion of areas near the construction causeway on the left bank downstream structure A4017 (fig. 10). The rock outcrop on and around the various spur dikes (fig. 10). There was an the downstream left (north) bank showed no signs of substan- area of substantial deposition near the location of pier 5 of tial change except for minor deposition along the toe of the 16 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
) ) ) ) ) ) ) b b d d c b b ( ( ( ( ( ( ( 1.43 3.03 2.82 1.79 5.95 1.94 2.90 1.85 6.25 4.65 1.67 1.06 2.03 2.20 2.76 2.05 2.96 1.22 1.68 c c c (ft/ft) scour hole Approximate frontal slope of
) ) ) ) b b b b 9 5 9 2 8 6 3 6 4 3 4 6 3 6 6 6 c ( ( ( ( (ft) 11 13 12 10 18 12 upstream hole from channel bed Depth of scour
- 6 b 20 46 66 15 44 60 34 52 69 35 49 64 57 57 58 46 45 49 66 43 49 58 76 61 56 (ft) distance be and bedrock Approximate of scour hole tween bottom
. (ft) 404 386 369 355 405 368 360 372 358 351 372 358 351 350 342 351 343 358 353 345 358 353 345 303 314 336 pier/bent elevation of Approximate bedrock near
27, 2016 −
(ft) 411 443 407 417 422 429 412 422 406 410 420 407 407 415 408 399 410 389 403 402 401 402 421 388 375 392 b b bent face elevation of Approximate scour hole at upstream pier/
a (ft) 411 410 406 415 421 420 412 420 406 410 420 407 407 415 407 399 409 389 403 402 401 402 403 379 375 392 minimum pier/bent elevation in channel-bed Approximate scour hole near
— — — — — (ft) 396.00 406.00 383.00 390.00 371.62 371.62 371.62 371.62 371.62 371.62 378.00 378.00 386.00 388.00 394.00 386.00 388.00 394.00 346.50 346.50 359.00 elevation Bottom of seal course
1 1 3 11 11 11 11 11 11 16 15 15 16 26 13 16 17 15 15 15 15 15 15 13 15 26 (ft) into bedrock Penetration
8 8 (ft) 11.5 10 32 24 28 32.9 33.5 33.5 32.9 33.5 33.5 29.5 29.5 24 24 24 24 24 24 24 24 26 26 26 Width Foundation information Type Drilled shaft Drilled shaft Drilled shaft Drilled shaft Footing Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Caisson Caisson Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft 6 7 8 9 4 5 6 5 6 7 5 6 7 2C 3C 4C 2C 3C 4C 11 15 16 16 17 10 12 MoDOT number pier/bent
MoDOT number structure Results near piers and bents from surveys on the Missouri River St. Louis, Missouri, May 23 A7577 A4017 A5585 Eastbound Westbound A5585 A3292 L0561 A4557 Eastbound Westbound A4557 A3047
23 24 25 26 27 Scour hole at this pier/bent is substantially affected by adjacent spur dike or construction dike. Scour hole at this pier/bent is substantially affected Poorly defined scour hole at this pier/bent. The point of lowest elevation in the scour hole near bridge pier/bent, not necessarily at upstream face. by upstream pier. Scour hole at this pier/bent is substantially affected Site a b c d (fig. 1) number Table 6. Table Datum of 1988] Vertical American ft, foot; —, not known/applicable; all elevations are in feet above the North Transportation; Missouri Department of [MoDOT, Results of Bathymetric and Velocimetric Surveys 17 A' 2,200 2,100 2,000 Footing Seal course Drilled shafts
Cap Pedestal Column Bent 9 Bent 1,900 epartment of ransportation, written commun., 2017 and top of bedroc line from 201 bridge plans Missouri 1,800 Substructural and superstructural details, approximate ground line, 1,700 1,600 t e Average water surface during 2016 survey (446.0 feet above the NAVD 88) Average water surface during 2011 survey (453.4 feet above the NAVD 88) Average water surface during 2010 survey (444.2 feet above the NAVD 88) e f
n Survey is along cross-section line shown in figure 6, facing downstream i
1,500 Approximate top of bedrock (from core logs) Bent 8 Bent Footing Seal course Drilled shafts 1,400 Cap Column Pedestal 1,300 of left (north) abutment , e c a f
l l i f
1,200 m o r f Part of bridge shown above Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey 1,100 Distance
Webwall Cap Column Bent 7 Bent 1,000 Drilled shafts 900
Webwall Drilled shafts Cap Column Bent 6 Bent 800 700 .
from bridge plans (2014)
Approximate ground line 600 Webwall Drilled shafts Cap Column Bent 5 Bent ey features, substructural and superstructural details, surveyed channel bed of structure A7577 on U.S. Highway 40 crossing the Missouri River K 500
A Figure 8. near St. Louis, Missouri 400
525 500 475 450 425 400 375 350 325
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E 18 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO B' 2,100 2,000
Seal course Drilled shafts Footing
1,900 Pedestal Cap Column Pier 6 Pier 1,800 epartment of ransportation, written commun., 2010 and top of bedroc line from 1 85 bridge plans Missouri 1,700 Substructural and superstructural details, approximate ground line, 1,600 1,500 t Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey e e Approximate ground line from bridge plans (1985) Approximate top of bedrock (from core logs) f
n Survey is along cross-section line shown in figure 6, facing downstream i
1,400
Seal course Footing Drilled shafts
Pedestal Column Cap Pier 5 Pier 1,300 of left (north) abutment , e c 1,200 a f
l l i f
m o r f Part of bridge shown above 1,100 Distance Average water surface during 2016 survey (446.0 feet above the NAVD 88) Average water surface during 2011 survey (453.4 feet above the NAVD 88) Average water surface during 2010 survey (444.2 feet above the NAVD 88) 1,000 900 Footing
Pedestal Column Cap Pier 4 Pier 800 700 . 600 ey features, substructural and superstructural details, surveyed channel bed of structure A4017 on U.S. Highway 40 crossing the Missouri River K
500 Figure 9. near St. Louis, Missouri B 400
525 500 475 450 425 400 375 350 325
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E
Results of Bathymetric and Velocimetric Surveys 19
0 3 20 0 3 25 FEE ME ERS 500 150 00 100 300 200
50 0 3 30 100 0 0
$ 0 3 35
Rock
outcrop 45
30 Spur dike Spur
20
0 3 0 15 Longitudinal spur dike spur Longitudinal 10 7 DEPOSITION 5 3
38 1 25 0 3 5 1 -1 E PLANATION -3
Pier 5
Pier 4
of J1000
of J1000
Remnant
Remnant -5
in figure 9 -7
Pier 6 Change in channel-bed elevation, feet
A4017
Cross section shown
Pier 5
A4017
Pier 4
A4017 0 3 50 B' SCOUR
Spur dike -10 B A' -15
A Construction
causeway -20
A7577
Bent 9
A7577
Bent 8
A7577
Bent 7 .
A7577
Bent 6 -30
in figure 8 0 3 55
Cross section shown
Spur dike Spur 0 0 00 ifference between surfaces created from bathymetric surveys of the Missouri River channel near structures A7577 and A4017 on U. S. Highway 40 D
FLOW 0 0 05
Base from ational Agriculture Imagery Program, 201 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 0 05 0 0 00 Figure 10. St. Louis, Missouri, on May 23, 2016, and July 29, 2011
38 1 20 38 1 15 38 1 10 38 1 05 20 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO -
b,c 5.8 8.5 (ft) 13.1 12.6 19.3 –4.3 –3.4 –7.6 –8.2 –3.7 12.1 12.6 12.0 near –15.7 –16.6 –16.8 e e e face(s) pier/bent upstream difference Maximum
(ft) 3.20 3.97 2.17 2.87 2.26 2.99 1.71 1.61 2.36 2.05 4.98 3.41 2.73 2.88 2.82 2.20 Standard deviation
b 0.16 0.86 2.23 0.77 0.53 0.51 0.77 (ft) –1.41 –0.27 –0.24 –0.20 –0.07 –1.77 –1.36 –0.38 –0.17 Mean
a,b (ft) 34.2 33.7 12.1 17.3 33.5 38.3 24.6 27.2 16.3 22.3 40.1 29.4 31.5 32.1 23.6 32.4 Max- imum previous survey surfaces
a,b (ft) Min- –21.7 –23.1 –14.1 –15.4 –21.6 –27.4 –26.6 –26.5 –19.9 –22.7 –29.7 –22.0 –21.2 –35.8 –17.6 –24.4 Statistics of differences between 2016 and imum
1.8 2.1 1.8 1.5 3.5 6.7 0.2 (ft) –7.4 –9.1 –8.6 –8.3 –8.1 –1.6 –0.8 –1.1 water- surface –13.2 Average Average elevation ) 2
ft 6 0.492 0.039 0.205 0.071 0.143 0.005 0.365 area –1.460 –0.165 –0.171 –2.409 –4.293 –4.701 –5.807 –4.675 –4.849 (x10 Surveyed
previous survey /s) 2,000 2,000 3 21,700 18,400 24,400 24,000 43,600 75,000 19,000 (ft –94,000 –19,000 –111,000 –114,000 –103,000 –109,000 –134,000 Discharge Difference between 2016 survey and
(ft) 444.2 453.4 432.0 443.2 430.0 440.4 428.4 438.2 410.2 421.8 398.2 396.5 383.8 403.7 390.3 391.6 water- , square foot; ft, foot; A, Huizinga (2011); B, Huizinga (2012); C, and others (2010); all elevations are A, Huizinga (2011); , square foot; ft, surface Average Average 2 elevation ) 2
ft 6 . 4.167 2.872 1.550 2.002 1.847 1.981 1.899 2.037 1.680 2.216 5.981 6.992 7.963 9.069 7.937 8.111 area d d d d d d d (x10 Surveyed
/s) 3 95,300 91,600 91,600 90,000 87,400 (ft 220,000 224,000 225,000 225,000 225,000 295,000 277,000 215,000 424,000 271,000 288,000 Discharge /s, cubic foot per second; ft 3 Previous survey . Date 07/29/11 08/01/11 08/02/11 08/02/11 08/03/11 10/18/10 10/21/10 10/21/10 10/22/10 10/25/10 07/07/09 10/20/10 07/08/09 10/19/10 10/02–03/08 05/12–13/09 A B A B A B A B A B C A A, C A, C A, C A of data Source
MoDOT number structure Summary information and bathymetric surface difference statistics from surveys on the Missouri Mississippi Rivers near St. Louis, Missouri, A7577/A4017 W A5585 E & A3292/L0561 W A4557 E & A3047 A6500 A1500 A4936/A1850
23 24 25 26 27 33 34 35 A positive value represents deposition, a negative scour. A The surveyed reach was substantially longer than in the 2016 survey The maximum or minimum value of change likely is near a vertical pier/bent face and affected by minor position variances. The maximum or minimum value of change likely is near a vertical pier/bent face and affected near the upstream pier/bent face was taken location of “approximate elevation scour hole at face” in tables 6 and 8. The maximum difference At the location of a new pier/bent compared to previous survey. Site a b c d e (fig. 1) number Table 7. Table May 23–27, 2016, and previous surveys ft Transportation; Missouri Department of [MoDOT, Datum of 1988] Vertical American in feet above the North Results of Bathymetric and Velocimetric Surveys 21 longitudinal spur dike (fig. 10). Although rock ultimately is causeway again is clearly evident between bents 6 and 7 an erodible material, its rate of erosion is substantially slower (fig. 8). The frequency distribution of bed elevations also than that of sand and silt (Richardson and Davis, 2001). was similar in shape in 2016 compared to 2010; however, a The difference between the survey on May 23, 2016, and lower percentage of grid cells had elevations between 420 and the previous nonflood survey on October 18, 2010, does not 426 ft, and a higher percentage of survey-grid cells had eleva- indicate substantial bed variation from 2010 to 2016, again tions between 429 and 443 ft (fig. 7). Again, the large mound with the exception of near the construction causeway on the of rock near bent 9 of upstream structure A7577 (fig. 8) also left bank and downstream from the spur dike on the left bank had been removed, with a resultant area of substantial scour (fig. 11). There was an area of substantial deposition near the indicated near that bent (fig. 11). location of pier 5 of old structure J1000, where a scour hole The vertically averaged velocity vectors indicate mostly present in the 2010 survey (Huizinga, 2011) has subsequently uniform flow throughout the reach (fig. 12). A maximum been filled (fig. 11). The mean difference between the bathy- velocity of about 8 feet per second (ft/s) was present in the metric surfaces was –1.41 ft (table 7), indicating moderate upstream channel thalweg and a minimum of 1 ft/s with flow channel degradation between the 2010 and 2016 surveys for reversal downstream from the various spur dikes in the reach the area common to both surveys. The net volume of cut in the (fig. 12). The flow constriction resulting from the presence reach from 2010 to 2016 was about 132,100 yd3, and the net of the construction causeway is clearly evident in the vec- volume of fill was about 30,800 yd3, resulting in a net loss of tors upstream from the bridges (fig. 12). A minor decrease in about 101,300 yd3 of sediment between 2010 and 2016. The velocity was observed downstream from bent 8 of upstream cross sections from the two surveys along the upstream face structure A7577 and pier 5 of downstream structure A4017, of the upstream structure A7577 bridge are not substantially likely exacerbated by the bent and pier being skewed to flow different from one another between bents 7 and 9 except near (fig. 12). Minor turbulence was present in all the sections the new bents, but the scouring effect of the construction (fig. 12).
22 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 3 20 0 3 25 FEE ME ERS 500 150 00 100 300 200
50 0 3 30 100 0 0
$ 0 3 35
Rock
outcrop 45
30 Spur dike Spur
20
0 3 0 15 Longitudinal spur dike spur Longitudinal 10 7 DEPOSITION 5 3
38 1 25 0 3 5 1 -1 E PLANATION -3
Pier 5
Pier 4
of J1000
of J1000
Remnant
Remnant -5
in figure 9 -7
Pier 6 Change in channel-bed elevation, feet
A4017
Cross section shown
Pier 5
A4017
Pier 4
A4017 0 3 50 B' SCOUR
Spur dike -10 B A' -15 .
A Construction
causeway -20
A7577
Bent 9
A7577
Bent 8
A7577
Bent 7
A7577
Bent 6 -30
in figure 8 0 3 55
Cross section shown
Spur dike Spur 0 0 00 ifference between surfaces created from bathymetric surveys of the Missouri River channel near structures A7577 and A4017 on U. S. Highway 40 D
FLOW 0 0 05
Base from ational Agriculture Imagery Program, 201 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88 Figure 11. St. Louis, Missouri, on May 23, 2016, and October 18, 2010
0 0 05 0 0 00
38 1 20 38 1 15 38 1 10 38 1 05 Results of Bathymetric and Velocimetric Surveys 23
38 1 25
0 0 05 0 0 00 0 3 55 0 3 50 0 3 5 0 3 0 0 3 35 0 3 30 0 3 25 38 1 20 A B E PLANATION Channel-bed elevation, in feet above the North American
Construction causeway Vertical Datum of 1988 450
445 Rock Spur dike Longitudinal spur dike outcrop 0 0 05 440
Remnant 435 of J1000 A7577 Pier 4 38 1 15 Bent 6 A4017 430 Pier 4 425 Small dunes and ripples A7577 Bent 7 Medium dunes 420
415
410
Remnant 405 of J1000 Pier 5 400 A7577 A4017 38 1 10 FLOW Bent 8 Pier 5 395
Medium dunes No data Small dunes and ripples $ Spur dike Vertically averaged velocity, in feet per second A7577 0−1 Bent 9 A4017 1−2 38 1 05 Pier 6 2−3 3−4 4−5 5−6 6−7 Survey date May 23, 2016 7−8 8−9 Spur dike B'Cross section shown Discharge 117,000 cubic feet per second in figure 9 Cross section shown A' 9−10 Average water-surface elevation 10−11 0 0 00 in figure 8 446.0 feet above the NAVD 88 11−12
Base from ational Agricultural Information Program, 201 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88 0 3 20
Figure 12. Bathymetry and vertically averaged velocities of the Missouri River channel near structures A7577 and A4017 on U.S. Highway 40 near St. Louis, Missouri. 24 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Dual Bridge Structure A5585 on State Highway had a minimum channel-bed elevation of about 410 ft (fig. 13; 364 table 6), about 6 ft below the average channel bed immediately upstream from the pier, whereas the scour hole at downstream Structure A5585 (site 24) consists of twin bridges on (westbound) pier 6 had a minimum channel-bed elevation of State Highway 364, crossing the Missouri River at RM 32.7, about 407 ft (fig. 13; table 6), about 4 ft below the average on the northwestern side of the St. Louis metropolitan area channel bed immediately upstream from the pier. The scour between Maryland Heights and St. Charles, Mo. (fig. 1). The hole at upstream (eastbound) pier 7 had a minimum channel- site was surveyed on May 24, 2016, and the average water- bed elevation of about 420 ft (fig. 13; table 6), whereas the surface elevation near the bridge, determined by the RTK scour hole at downstream (westbound) pier 7 had a minimum GNSS tide solution, was 434.1 ft (table 5). Flow on the Mis- channel-bed elevation of about 415 ft (fig. 13; table 6), both souri River was about 110,000 ft3/s during the survey (table 5), of which are only about 3 ft below the average channel bed which does not account for flow through a side channel near immediately upstream from the pier. the site. The flow measured at structures A3292 and L0561 Information from bridge plans indicates that the main just a little later in the day was about 116,000 ft3/s, and was channel piers of both bridges of structure A5585 are founded 114,000 ft3/s still later on the same day at dual bridge structure on shafts drilled 11 ft into bedrock (figs. 15, 16; table 6). A4557 (table 5). Depth of bed material between bedrock and the bottom of The survey area was about 1,640 ft long and about the various scour holes at dual bridge structure A5585 ranged 1,230 ft wide, extending from bank to bank in the main chan- from 34 to 69 ft because of the sloping bedrock in the area nel (fig. 13). The upstream end of the survey area was about (figs. 15, 16; table 6). The approximate minimum channel-bed 720 ft upstream from the centerline of dual bridge structure elevation in each of the scour holes was substantially higher A5585 at pier 5 (fig. 13). The approximate channel-bed than the bottom of the seal course elevation at each pier of elevations ranged from about 406 to 424 ft for most of the 371.62 ft (figs. 15, 16; table 6). surveyed area (5th to 95th percentile range of the bathymetric The difference between the survey on May 24, 2016, and data; table 5; fig. 14), except along the channel thalweg where the previous survey on August 1, 2011, indicates an approxi- medium to large dunes caused local approximate minimum mately even split of aggradation and degradation throughout channel-bed elevations of about 399 ft (fig. 13; table 5). The the reach, except near the rock outcrop on the left (north) bank thalweg was along the outside of the river bend on the left (fig. 17). Overall, there was minimal net change between the (north) bank, and was about 10 to 15 ft deeper than the bed surveys, as indicated by the mean difference being +0.16 ft in the middle of the channel (fig. 13). Numerous small dunes (table 7). The net volume of cut in the reach from 2011 to and ripples were present throughout the middle of the channel, 2016 was about 74,700 yd3, and the net volume of fill was and a nearly planar bed area was present with no prominent about 86,400 yd3, resulting in a net gain of about 11,700 yd3 features along the right (south) bank (fig. 13). As in previous of sediment between 2011 and 2016. There was net deposition surveys (Huizinga, 2011, 2012), a rock outcrop was present on near pier 5 and net scour near pier 6 (figs. 15–17). A substan- the left (north) bank throughout the reach (fig. 13). tial scour hole near upstream (eastbound) pier 7 caused in part Scour holes were present near the main channel piers of by debris trapped on that pier in the 2011 survey has filled in structure A5585 (fig. 13), and generally more substantial scour (fig. 15), as evidenced by the deposition in a horseshoe shape was associated with the upstream (eastbound) piers than the around the nose of that pier (fig. 17). The frequency distribu- downstream (westbound) piers. The scour hole at upstream tion of channel-bed elevations was slightly narrower in 2016 (eastbound) pier 5 had a minimum channel-bed elevation of than in 2011; a greater percentage of survey-grid cells were about 406 ft (fig. 13; table 6), about 8 ft below the average present at elevations between 410 and 416 ft than in 2011 channel bed immediately upstream from the pier, whereas the (fig. 14). The rock outcrop on the left (north) bank showed no scour hole at downstream (westbound) pier 5 had a minimum signs of substantial change except for areas of minor deposi- channel-bed elevation of about 407 ft (fig. 13; table 6), about tion on several rock ledges (fig. 17). As stated for the previ- 6 ft below the average channel bed immediately upstream ous site (Structures A7577 and A4017 on U.S. Highway 40), from the pier. The scour hole at upstream (eastbound) piers 6 although rock ultimately is an erodible material, its rate of and 7 extended to near the corresponding downstream (west- erosion is substantially slower than that of sand and silt (Rich- bound) pier. The scour hole at upstream (eastbound) pier 6 ardson and Davis, 2001).
Dual Bridge Structure A5585 on State Highway 364. Results of Bathymetric and Velocimetric Surveys 25
38 15 38 20
0 31 35 0 31 30 0 31 25 0 31 20 0 31 15 0 31 10 E PLANATION 38 10 A B Channel-bed elevation, in feet above the North American Vertical Datum of 1988 440 Rock outcrop Rock outcrop Rock outcrop 435
430
425
420 0 31 35 Large dune Medium dunes Large dune Medium dunes Medium dune 415
410 38 05
c-c' f-f' Pier 5 405
Longitudinal sections 400 shown in figure 62 FLOW 395 Small dunes and ripples Small dunes and ripples g-g' No data d-d' Pier 6
Longitudinal sections shown in figure 62
e-e' h-h' Pier 7
Planar bed
Spur dike 38 0 31 30 $
Cross section shown Survey date May 24, 2016 Cross section shown in figure 16 in figure 15 A' B' Discharge 110,000 cubic feet per second Average water-surface elevation 434.1 feet above the NAVD 88
Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88 0 31 15 0 31 20
Figure 13. Bathymetric survey of the Missouri River channel near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri. 26 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
1.4 100 E PLANATION 90 [ft3/s, cubic foot per second] 1.2 Frequency distribution 80 2016 survey data; 110,000 ft3/s 1.0 70 2011 survey data; 224,000 ft3/s 2010 survey data; 60 3 0.8 91,600 ft /s Cumulative percentage 50 2016 survey data; 3 0.6 110,000 ft /s 40 2011 survey data; indicated elevation 224,000 ft3/s 2010 survey data; 0.4 30 3
Percentage of total survey-grid cells 91,600 ft /s
20
0.2 Cumulative percentage of survey-grid cells lower than 10
0 0 390 395 400 405 410 415 420 425 430 435 440 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 14. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri, on May 24, 2016, compared to previous surveys.
The difference between the survey on May 24, 2016, and because a greater percentage of survey-grid cells were present the previous nonflood survey on October 21, 2010 (fig. 18), at elevations above 420 ft than in 2010 (fig. 14). indicates very minor scour throughout the reach from the 2010 The vertically averaged velocity vectors indicate mod- to 2016 surveys, resulting in a mean difference of –0.24 ft erate to substantial turbulence throughout the reach, rang- between the bathymetric surfaces (table 7). The net volume of ing from about 2 to 10 ft/s (fig. 19). Flow was angled to the cut in the reach from 2010 to 2016 was about 49,800 yd3, and left (north) in the upstream reach because of the bend in the the net volume of fill was about 36,600 yd3, resulting in a net river, and numerous local velocity minima were on the right loss of about 13,200 yd3 of sediment between 2010 and 2016. (south) side of the channel (fig. 19). Substantial turbulence The flow conditions of the 2010 survey were similar to the was observed in the channel thalweg, particularly downstream 2016 survey (table 7), which may help explain the similarity from the bridges (fig. 19). Piers 5 through 7 were aligned with between the surveys; however, the frequency distribution of flow, resulting in minimal additional turbulence downstream bed elevations was substantially wider in 2016 than in 2010, (fig. 19). Results of Bathymetric and Velocimetric Surveys 27
A'
1,600 Pier 8 Pier Cap Piles Column Pedestal Footing Seal course 1,500 1,400 Seal course Footing Drilled shafts
Pedestal Cap Column Pier 7 Pier Department of Transportation, written commun., 2010). and top of bedrock line from 1994 bridge plans (Missouri 1,300 Substructural and superstructural details, approximate ground line, 1,200 Seal course Footing Drilled shafts
Pedestal Cap Column Pier 6 Pier t e e f
n Survey is along cross-section line shown in figure 13, facing downstream. i 1,100
. 1,000 from 1994 bridge plans Approximate ground line Seal course Footing Drilled shafts Cap Pedestal Column
of left (north) abutment , Pier 5 Pier e c a f 900
l l i f
m o r f Part of bridge shown above 800 Distance 700 Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey Approximate top of bedrock (from core logs) 600 500 ey features, substructural and superstructural details, surveyed channel bed along the upstream face of bri dge dual bridge K 400
Average water surface during 2016 survey (434.1 feet above the NAVD 88) Average water surface during 2011 survey (443.2 feet above the NAVD 88) Average water surface during 2010 survey (432.0 feet above the NAVD 88) Pier 4 Pier Cap Pedestal Column Figure 15. structure A5585 on State Highway 364 crossing the Missouri River near St. Louis, Footing A 300
525 500 475 450 425 400 375 350 325
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E 28 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
B'
1,600 Pier 8 Pier Cap Piles Column Pedestal Footing Seal course 1,500 1,400 Seal course Footing Drilled shafts
Pedestal Cap Column Pier 7 Pier Department of Transportation, written commun., 2010). 1,300 and top of bedrock line from 1994 bridge plans (Missouri Substructural and superstructural details, approximate ground line, 1,200 Seal course Footing Drilled shafts
Pedestal Cap Column Pier 6 Pier t e e f
n Survey is along cross-section line shown in figure 13, facing downstream. 1,100 i
. 1,000 from 1994 bridge plans Approximate ground line Seal course Footing Drilled shafts Cap Pedestal Column
of left (north) abutment , Pier 5 Pier e c a 900 f
l l i f
m o r f Part of bridge shown above 800 Distance 700 Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey Approximate top of bedrock (from core logs) 600 500 ey features, substructural and superstructural details, surveyed channel bed along the upstream face of downstream bri dge dual bridge K 400
Average water surface during 2016 survey (434.1 feet above the NAVD 88) Average water surface during 2011 survey (443.2 feet above the NAVD 88) Average water surface during 2010 survey (432.0 feet above the NAVD 88) Pier 4 Pier Cap Pedestal Column Footing B Figure 16. structure A5585 on State Highway 364 crossing the Missouri River near St. Louis, 300
525 500 475 450 425 400 375 350 325
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E
Results of Bathymetric and Velocimetric Surveys 29
0 31 20 0 31 15
FEE
ME ERS 0 31 10 75 250 200 50 150 100 25 50 0 0
0 31 15 $ Rock outcrop Rock 30 20
38 20 15 0 31 20 10 7 DEPOSITION 5 3
1 Rock outcrop Rock
in figure 16
Pier 7 Pier Pier 5 Pier Pier 6 Pier -1
Cross section shown B' -3 B E PLANATION
-5 0 31 25 A' -7 A -10 Change in channel-bed elevation, feet SCOUR -15
. Spur dike Spur in figure 15 -20
Cross section shown -30 -45
38 15
0 31 30
Rock outcrop Rock 0 31 35 ifference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A5585 on S tate Highway 364 D
FLOW
Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 17. near St. Louis, Missouri, on May 24, 2016, and August 1, 2011
0 31 35 0 31 30 38
38 10 38 05
30 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 31 20 0 31 15
FEE
ME ERS 0 31 10 75 250 200 50 150 100 25 50 0 0
0 31 15 $ Rock outcrop Rock 30 20 15
38 20 0 31 20 10 7 DEPOSITION 5 3
1 Rock outcrop Rock
in figure 16
Pier 7 Pier Pier 5 Pier Pier 6 Pier -1
Cross section shown B' -3 B E PLANATION
-5 0 31 25 A' -7 A -10 Change in channel-bed elevation, feet SCOUR .
-15 Spur dike Spur in figure 15 -20
Cross section shown -30 -45
38 15
0 31 30
Rock outcrop Rock 0 31 35 ifference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A5585 on S tate Highway 364 D
FLOW
Figure 18. near St. Louis, Missouri, on May 24, 2016, and October 21, 2010
Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 31 35 0 31 30 38
38 10 38 05 Results of Bathymetric and Velocimetric Surveys 31
38 15 38 20
0 31 35 0 31 30 0 31 25 0 31 20 0 31 15 0 31 10 E PLANATION 38 10 A B Channel-bed elevation, in feet above the North American Vertical Datum of 1988 440 Rock outcrop Rock outcrop Rock outcrop 435
430
425
420 0 31 35 Large dune Medium dunes Large dune Medium dunes Medium dune 415
410 38 05
Pier 5 405
400 FLOW 395 Small dunes and ripples Small dunes and ripples No data Pier 6 $
Vertically averaged velocity, Pier 7 in feet per second Planar bed 0−1 1−2
Spur dike 0 31 30 38 2−3 3−4 4−5 5−6 6−7 Cross section shown Survey date May 24, 2016 Cross section shown in figure 16 7−8 in figure 15 A' B' Discharge 110,000 cubic feet per second 8−9 9−10 Average water-surface elevation 10−11 434.1 feet above the NAVD 88 11−12
Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS 0 31 15 0 31 20 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 19. Bathymetry and vertically averaged velocities of the Missouri River channel near dual bridge structure A5585 on State Highway 364 near St. Louis, Missouri. 32 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Structures A3292 and L0561 on Interstate 70 about 57 ft of bed material was present between the bottom of the scour hole and bedrock near the upstream pier (fig. 23; Structures A3292 and L0561 (site 25) are dual bridges on table 6). Pier 16 of downstream structure L0561 is founded on Interstate 70, crossing the Missouri River at RM 29.6, on the a caisson on bedrock, and the bottom of the minor local scour northwestern side of the St. Louis metropolitan area between hole near this pier was about 58 ft above the bottom of the Maryland Heights and St. Charles, Mo. (fig. 1). The site was caisson and bedrock (fig. 24; table 6). surveyed on May 24, 2016, and the average water-surface Larger scour holes were present near the right main elevation near the bridge, determined by the RTK GNSS tide channel piers of structures A3292 and L0561 (fig. 20). The solution, was 431.8 ft (table 5). Flow on the Missouri River scour hole at upstream pier 16 had an approximate minimum was about 116,000 ft3/s during the survey (table 5). channel-bed elevation of about 399 ft (fig. 23; table 6), about The survey area was about 1,640 ft long and varied in 12 ft below the average channel bed immediately upstream width from about 1,490 ft wide at the upstream end to about from the pier, whereas the scour hole at downstream pier 17 1,070 ft wide at the downstream end, extending from bank to had an approximate minimum channel-bed elevation of about bank in the main channel (fig. 20). The upstream end of the 389 ft (fig. 24; table 6), about 18 ft below the average channel survey area was about 690 ft upstream from the centerline bed immediately upstream from that pier. Information from of structures A3292 and L0561 (fig. 20). The approximate bridge plans indicates that pier 16 of upstream structure A3292 channel-bed elevations ranged from about 404 to 423 ft for is founded on shafts drilled 17 ft into bedrock, and about 57 ft most of the surveyed area (5th to 95th percentile range of the of bed material was present between the bottom of the scour bathymetric data; table 5; fig. 21), except downstream from hole and bedrock (fig. 23; table 6). Pier 17 of structure L0561 the spur dike on the left (northwest) bank downstream from is founded on a caisson on bedrock, and about 46 ft of bed the bridge, near the piers, and in the downstream channel thal- material was present between the bottom of the scour hole and weg (fig. 20). The thalweg was on the right (southeast) bank bedrock (fig. 24; table 6). throughout the reach and was about 8 to 15 ft deeper than the The vertically averaged velocity vectors indicate mostly channel bed in the middle of the channel (fig. 20). The channel uniform flow throughout the channel, ranging from about and thalweg deepened downstream from the bridges (fig. 20), 3 to 8 ft/s (fig. 22). Flow was angled to the right (southeast) likely because of the contraction of the channel caused by the in the upstream reach because of the downstream contraction building on the left bank downstream from the bridges. On the (fig. 22). Exceptions to uniform conditions include substantial upstream left (northwest) side, deposits reached an elevation turbulence observed downstream from the right (southeast) of about 423 ft (fig. 20). A line of medium dune features were main channel piers of structures A3292 and L0561 and minor detected in the middle of the channel through the survey reach, turbulence in the downstream-most transect (fig. 22). The right and numerous smaller dunes and ripples were present through- main channel piers were aligned with flow, whereas the left out the channel reach (fig. 20). A localized deep scour hole main channel piers were not. at the end of the shallow spur dike between the downstream The difference between the survey on May 24, 2016, bridge and the building on the left bank had a minimum and the previous survey on August 2, 2011 (fig. 25), indicates channel-bed elevation of about 397 ft (fig. 20). As in previous moderate deposition throughout the reach from 2011 to 2016, surveys (Huizinga, 2011, 2012), stone revetment was present resulting in a mean difference of +2.23 ft between the bathy- on the right (southeast) bank throughout the reach (fig. 20). metric surfaces (table 7). The net volume of cut in the reach A minor scour hole near the left main channel piers (pier from 2011 to 2016 was about 26,000 yd3, and the net volume 15 of upstream structure A3292 and pier 16 of downstream of fill was about 188,800 yd3, resulting in a net gain of about structure L0561; fig. 20) had an approximate minimum 162,800 yd3 of sediment between 2011 and 2016. Moderate channel-bed elevation of about 407 and 409 ft, respectively to substantial scour had been observed between the 2010 and (table 6), about 13 ft below the average channel bed imme- 2011 surveys (Huizinga, 2012), but ongoing sediment trans- diately upstream from pier 15 of structure A3292 (fig. 20; port processes seem to have fully replenished the sediment table 6). The scour hole was deeper on the right (southeast) deposits at this site. There was substantial deposition in the side of pier 15 (fig. 20), likely exacerbated by the effects of scour hole caused by a sizable debris raft upstream from pier a small debris raft trapped on the nose of that pier and the 15 of structure A3292 (fig 25; Huizinga, 2012). Areas of mod- angled flow near the left main channel piers caused by the erate scour were present downstream from the spur dike and constriction downstream (fig. 22). Information from bridge along the left (northwest) bank downstream from the bridges plans indicates that pier 15 of upstream structure A3292 is at the constriction, and minor localized scour of the deposits founded on shafts drilled about 16 ft in bedrock (table 6), and was present along the upstream left (northwest) bank (fig. 25).
Structures A3292 and L0561 on Interstate 70. Results of Bathymetric and Velocimetric Surveys 33
38 5 5 38 5 50 38 5 55 38 6 05
38 6
0 2 10 0 2 05 0 2 E PLANATION A B Channel-bed elevation, in feet above the North American Vertical Datum of 1988 435
430 0 2 10
425
Small dunes and ripples 420 Stone revetment 415
Spur dike A3292 410 Pier 15 c c' e e' L0561 Pier 16 405
400
0 2 05 395 Longitudinal sections shown in figure 63 390 38 5 0 FLOW Medium dunes 385 Medium dunes Medium dunes
Medium dunes
d d' f f' L0561 Pier 17 A3292 Pier 16 0 2 $ Small dunes and ripples
Small dunes and ripples Survey date May 24, 2016 Stone revetment Discharge 116,000 cubic feet per second Average water-surface elevation Stone revetment Cross section shown Cross section shown in figure 23 A' B' in figure 24 431.8 feet above the NAVD 88
0 28 55 Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth 0 28 50 0 28 5 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 20. Bathymetric survey of the Missouri River channel near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri. 34 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
1.8 100 E PLANATION 3 1.6 90 [ft /s, cubic foot per second]
Frequency distribution 80 1.4 2016 survey data; 116,000 ft3/s 70 2011 survey data; 1.2 225,000 ft3/s 2010 survey data; 60 3 1.0 91,600 ft /s Cumulative percentage 50 2016 survey data; 0.8 116,000 ft3/s 40 2011 survey data; indicated elevation 225,000 ft3/s 0.6 2010 survey data; 30 3
Percentage of total survey-grid cells 91,600 ft /s 0.4 20 Cumulative percentage of survey-grid cells lower than
0.2 10
0 0 385 390 395 400 405 410 415 420 425 430 435 440 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 21. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri, on May 24, 2016, compared to previous surveys.
The cross sections from the 2016 survey show the pattern of in a net gain of about 56,000 yd3 of sediment between 2010 deposition in the thalweg and scour on the left (northwest) and 2016. There was substantial deposition in the scour hole side of the channel compared to the 2011 survey (figs. 23, 24). caused by a debris raft upstream from pier 15 of structure The frequency distribution of bed elevations was narrower in A3292 (Huizinga, 2011) and in the middle of the channel 2016 than in 2010; however, a greater percentage of survey- at and immediately downstream from the bridges (fig. 26). grid cells were present at elevations between 420 and 424 ft Moderate localized scour was observed near the right main than in 2011 (fig. 21). The stone revetment on the upstream channel piers and along the toe of the upstream right (south- right (southeast) bank seems to have experienced deposition, east) bank (fig. 26). The cross sections from the two sur- whereas the revetment near the bridge seems to have experi- veys further indicate the general similarities (figs. 23, 24). enced minor scour (fig. 25), but this may be a function of posi- The frequency distribution of bed elevations was similar in tional variations between the surveys. Huizinga (2011) noted shape but slightly wider in 2016 than in 2010, and a greater issues with horizontal positioning at this site during the survey percentage of survey-grid cells were at a higher elevation in in October 2010. Substantial deposition or scour apparent 2016 than 2010 (fig. 21). The localized scour observed on the at the faces of the piers likely results from minor horizontal stone revetment on the right (southeast) bank in 2011 (Huiz- positional variances between the surveys (see the “Uncertainty inga, 2012) is present in the difference between the 2016 and Estimation” section). 2010 surveys (fig. 26), but this difference may be a function The difference between the survey on May 24, 2016, of positional variations between the surveys. Huizinga (2011) and the previous nonflood survey on October 21, 2010 noted issues with horizontal positioning at this site during the (fig. 26), does not indicate substantial bed variation from survey in October 2010. As with all difference maps in this 2010 to 2016, resulting in a mean difference of +0.86 ft report, substantial deposition or scour apparent at the faces between the bathymetric surfaces (table 7). The net volume of the piers results from minor horizontal positional vari- of cut in the reach from 2010 to 2016 was about 33,000 yd3, ances between the surveys (see the “Uncertainty Estimation” and the net volume of fill was about 89,000 yd3, resulting section). Results of Bathymetric and Velocimetric Surveys 35
38 5 5 38 5 50 38 5 55 38 6 05
38 6
0 2 10 0 2 05 0 2 E PLANATION A B Channel-bed elevation, in feet above the North American Vertical Datum of 1988 435
430 0 2 10
425
Small dunes and ripples 420 Stone revetment 415
Spur dike A3292 410 Pier 15 L0561 Pier 16 405
400
0 2 05 395
390 38 5 0 FLOW Medium dunes 385 Medium dunes Medium dunes
Medium dunes $ L0561 Pier 17 A3292 Pier 16 0 2 Vertically averaged velocity, in feet per second 0−1 1−2 Small dunes and ripples 2−3 3−4 4−5 Small dunes and ripples 5−6 6−7 Survey date May 24, 2016 Stone revetment 7−8 Discharge 116,000 cubic feet per second 8−9 9−10 Average water-surface elevation 10−11 Stone revetment Cross section shown Cross section shown in figure 23 A' B' in figure 24 431.8 feet above the NAVD 88 11−12
0 28 55 Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth 0 28 50 0 28 5 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 22. Bathymetry and vertically averaged velocities of the Missouri River channel near structures A3292 and L0561 on Interstate 70 near St. Louis, Missouri. 36 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
A'
3,300 Pier 17 Pier Cap Column Footing Pedestal 3,200 Seal course Drilled shafts 3,100 1973 bridge plans 3,000 epartment of ransportation, written commun., 2010 and top of bedroc line from 1 73 bridge plans Missouri Approximate ground line from Substructural and superstructural details, approximate ground line, Approximate top of bedrock (from core logs) 2,900 Seal course
Footing Drilled shafts
Pedestal Cap Column Pier 16 Pier 2,800 t e e f
n Survey is along cross-section line shown in figure 20, facing downstream i
2,700 2,600 of left (north) abutment , e c a 2,500 Average water surface during 2016 survey (431.8 feet above the NAVD 88) Average water surface during 2011 survey (440.4 feet above the NAVD 88) Average water surface during 2010 survey (430.0 feet above the NAVD 88) f
l l i f
Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey m o r f Part of bridge shown above 2,400 Seal course
Footing Drilled shafts
Distance Pedestal Cap Column Pier 15 Pier 2,300 2,200 2,100 . 2,000 ey features, substructural and superstructural details, surveyed channel bed of structure A3292 on Interstate 70 crossing t he Missouri River K Seal course
Footing Drilled shafts
Pedestal Column
Cap 1,900 Pier 14 Pier Figure 23. near St. Louis, Missouri A 1,800
525 500 475 450 425 400 375 350 325 300
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E Results of Bathymetric and Velocimetric Surveys 37 B' 3,300
Caisson
Pedestal Cap Column Pier 18 Pier 3,200 3,100 3,000 epartment of ransportation, written commun., 2010 and top of bedroc line from 1 55 bridge plans Missouri 1955 bridge plans Substructural and superstructural details, approximate ground line, Approximate ground line from 2,900 Approximate top of bedrock (from core logs) Caisson Pedestal
Cap Column
2,800 Pier 17 Pier t e e f
n Survey is along cross-section line shown in figure 20, facing downstream i
2,700 2,600 of left (north) abutment , e c a f 2,500
l l i f Average water surface during 2016 survey (431.8 feet above the NAVD 88) Average water surface during 2011 survey (440.4 feet above the NAVD 88) Average water surface during 2010 survey (430.0 feet above the NAVD 88) Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey
m o r f Part of bridge shown above 2,400 Distance
Caisson
Pedestal Column Cap Pier 16 Pier 2,300 2,200 2,100 . 2,000 ey features, substructural and superstructural details, surveyed channel bed of structure L0561 on Interstate 70 crossing t he Missouri River K
1,900
Caisson
Pedestal Column Cap Pier 15 Pier Figure 24. near St. Louis, Missouri B
1,800
525 500 475 450 425 400 375 350 325 300
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E 38 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO FEE ME ERS 75 250 200 50 150 100 25 50
38 6 05 0 0 0 2 $ 45 30
38 6
20
Stone revetment Stone 0 28 5 15 10 7 DEPOSITION 5
Spur dike 3
0 2 05 Stone revetment 1
in figure 24
L0561
Pier 17
L0561
Pier 16 -1
Cross section shown B' -3 B E PLANATION 38 5 55 -5
A3292
Pier 16
A3292
Pier 15 A' -7 A Change in channel-bed elevation, feet -10 SCOUR -15 -20 .
in figure 23 -30
Cross section shown 0 28 50 -45
38 5 50
Stone revetment Stone 0 2 10 ifference between surfaces created from bathymetric surveys of the Missouri River channel near structures A3292 and L0561 on I nterstate 70 D
FLOW 38 5 5 Figure 25. St. Louis, Missouri, on May 24, 2016, and August 2, 2011
Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
38 5 0 0 2
0 2 05 0 28 55 0 2 10 Results of Bathymetric and Velocimetric Surveys 39 FEE ME ERS 75 250 200 50 150 100 25 50
38 6 05 0 0 0 2 $ 45 30
38 6
20
Stone revetment Stone 0 28 5 15 10 7 DEPOSITION 5
Spur dike 3
0 2 05 Stone revetment 1
in figure 24
L0561
Pier 17
L0561
Pier 16 -1
Cross section shown B' -3 B E PLANATION 38 5 55 -5
A3292
Pier 16
A3292
Pier 15 A' -7 A Change in channel-bed elevation, feet -10 SCOUR -15 . -20
in figure 23 -30
Cross section shown 0 28 50 -45
38 5 50
Stone revetment Stone 0 2 10 ifference between surfaces created from bathymetric surveys of the Missouri River channel near structures A3292 and L0561 on I nterstate 70 D
FLOW 38 5 5 Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 26. St. Louis, Missouri, on May 24, 2016, and October 21, 2010
38 5 0 0 2
0 2 05 0 28 55 0 2 10 40 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Dual Bridge Structure A4557 on State Highway either upstream or downstream pier 4C (fig. 27); however, 370 the spur dike adjacent to these piers caused a local deep hole that reached a minimum channel-bed elevation of about 403 ft Structure A4557 (site 26) consists of twin bridges on downstream from the westbound pier (fig. 27; table 6). These State Highway 370, crossing the Missouri River at RM 27.0, piers essentially were embedded in the rock of the dike, which on the northwestern side of the St. Louis metropolitan area will limit or prevent additional scour near them. Material from between Bridgeton and St. Charles, Mo. (fig. 1). The site was the toe of the spur dike extended to downstream (westbound) surveyed on May 24, 2016, and the average water-surface pier 3C and may limit scour on the right (south) side of that elevation near the bridge, determined by the RTK GNSS tide pier as well; however, flow seems to be deflected towards the solution, was 429.9 ft (table 5). Flow on the Missouri River left (north) upstream from pier 3C (fig. 29) and may affect the was about 114,000 ft3/s during the survey (table 5). scour hole near these piers. The survey area was about 1,640 ft long and about The vertically averaged velocity vectors indicate mostly 1,280 ft wide, extending from bank to bank in the main uniform flow throughout most of the reach, ranging from channel (fig. 27). The upstream end of the survey area was about 2 to 8 ft/s (fig. 29). Exceptions to uniform conditions about 670 ft upstream from the centerline of structure A4557 include flow reversal on the right (southeast) bank down- (fig. 27). The approximate channel-bed elevations ranged stream from the spur dike (fig. 29). Moderate turbulence also from about 399 to 417 ft for most of the surveyed area (5th to was observed in the downstream-most transect (fig. 29). All 95th percentile range of the bathymetric data; table 5; fig. 28), the piers were aligned with flow, as indicated by little to no except near the piers and along the toe of the rock outcrop turbulence observed downstream that can be directly attributed along the left (northwest) side of the channel, which had a to the piers (fig. 29). minimum channel-bed elevation of about 392 ft (fig. 27). A substantial scour hole was observed at the railroad The approximate minimum channel-bed elevation of 388 ft bridge pier upstream from pier 2C (fig. 27). The hole had a was at the bottom of the scour hole at the railroad bridge pier minimum channel-bed elevation of 388 ft at the nose of the upstream from pier 2C (fig. 27; table 5). A series of medium pier, about 23 ft below the average channel bed immediately dune features were observed in the channel thalweg, with upstream from the pier (fig. 27). A smaller scour hole also numerous small dunes and ripples detected throughout most was present at the railroad bridge pier upstream from pier of the rest of the channel, and a nearly planar bed area with no 4C, which had a minimum channel-bed elevation of 403 ft at prominent features along the right (southeast) bank (fig. 27). the nose of the pier, about 5 ft below the average channel bed As in previous surveys (Huizinga, 2011, 2012), a spur dike immediately upstream from the pier (fig. 27). The scour holes was present under the downstream bridge on the right (south- at the railroad bridge piers did not seem to affect the scour at east) bank (fig. 27). piers 2C or 4C of structure A4557 (fig. 27). Small scour holes were present near the main chan- Information from bridge plans indicates that the main nel piers, except those near the spur dike on the right side of channel piers of both bridges of structure A4557 are founded the channel (pier 4C at both bridges; fig. 27). At pier 2C, the on shafts drilled 15 ft into bedrock (figs. 30, 31; table 6). scour hole near the upstream (eastbound) pier had a minimum Depth of bed material between bedrock and the bottom of channel-bed elevation of about 403 ft (fig. 27; table 6), about the various scour holes at dual bridge structure A4557 ranged 4 ft below the average channel bed immediately upstream from 43 to 66 ft because of the sloping bedrock and channel from the pier; and the scour hole at the downstream (west- bed in the area (figs. 30, 31; table 6). The minimum channel- bound) pier had a minimum channel-bed elevation of about bed elevation in each of the scour holes was more than 9 ft 401 ft (fig. 27; table 6), about 6 ft below the average chan- higher than the bottom of the seal course elevation at each pier nel bed immediately upstream from the pier. At pier 3C, the (figs. 30, 31; table 6). scour hole at the upstream pier had a minimum channel-bed The difference between the survey on May 24, 2016, and elevation of about 402 ft (fig. 27; table 6), about 6 ft below the previous survey on August 2, 2011 (fig. 32), does not indi- the average channel bed immediately upstream from the pier; cate substantial bed variation from 2011 to 2016, as indicated and the scour hole at the downstream pier also had a minimum by a mean difference of only –0.07 ft between the bathymetric channel-bed elevation of about 402 ft (fig. 27; table 6), about surfaces (table 7). The net volume of cut in the reach from 6 ft below the average channel bed immediately upstream 2011 to 2016 was about 44,600 yd3, and the net volume of from that pier. Essentially, no scour hole was present around fill was about 39,800 yd3, resulting in a net loss of only about
Dual Bridge Structure A4557 on State Highway 370. Results of Bathymetric and Velocimetric Surveys 41
38 7 50 38 7 55 38 8 05 38 8 10 38 8
0 28 10 0 28 05 0 28 0 27 55 A B E PLANATION Channel-bed elevation, in feet above the North American Vertical Datum of 1988 435 Spur dike
Rock outcrop Rock outcrop 430
425
420
415
0 28 10 Medium dunes Medium dunes Medium dunes 410
38 7 5
405
Railroad 400 bridge pier f f' c-c' e-e' Pier 2C 395 FLOW 390 Longitudinal sections Longitudinal sections shown in figure 65 shown in figure 63 No data Small dunes and ripples Small dunes and ripples Submerged object d-d' 0 28 05 Pier 3C
g g' Planar bed Spur dike Railroad Pier 4C $ bridge pier Planar bed
Survey date May 24, 2016
Cross section shown Cross section shown Discharge 114,000 cubic feet per second 0 28 38 7 0 in figure 30 A' B' in figure 31 Average water-surface elevation 429.9 feet above the NAVD 88
Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth 0 27 50 0 27 5 0 27 0 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 27. Bathymetric survey of the Missouri River channel near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri. 42 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
2.25 100 E PLANATION 3 2.00 90 [ft /s, cubic foot per second] Frequency distribution 80 2016 survey data; 1.75 114,000 ft3/s 2011 survey data; 70 3 1.50 224,000 ft /s 2010 survey data; 60 90,000 ft3/s 1.25 Cumulative percentage 50 2016 survey data; 3 1.00 114,000 ft /s 2011 survey data; 40 indicated elevation 225,000 ft3/s 0.75 2010 survey data; 30 90,000 ft3/s Percentage of total survey-grid cells 0.50 20 Cumulative percentage of survey-grid cells lower than 0.25 10
0 0 385 390 395 400 405 410 415 420 425 430 435 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 28. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri, on May 24, 2016, compared to previous surveys.
4,800 yd3 of sediment between 2011 and 2016. There was an the net volume of fill was about 33,300 yd3, resulting in a net area of scour around the railroad bridge pier upstream from loss of only about 13,700 yd3 of sediment between 2010 and pier 2C and an area of deposition in the middle of the channel 2016. There was an area of scour around the railroad bridge upstream from the railroad bridge (fig. 32). The cross sections pier upstream from pier 2C, and some additional scour in the from the two surveys were similar to one another except in thalweg downstream from the bridges; however, an area of the area between the left bank and pier 2C (figs. 30, 31). The deposition was present in the reach upstream from the railroad frequency distribution of bed elevations were of remarkably bridge, and localized deposition was present along the right similar shape in all three of the surveys to date at this site (southeast) side of the channel downstream from the bridges (fig. 28), despite the difference in discharge (table 7). The rock (fig. 33). The cross sections from these two surveys also were outcrop on the downstream left (northwest) bank showed no similar to one another except in the area between the left signs of substantial change except for minor deposition along bank and pier 2C (figs. 30, 31). As mentioned in the previ- the toe of the bank (fig. 32). As with all difference maps in this ous paragraph, the frequency distribution of bed elevations report, substantial deposition or scour apparent at the faces were of remarkably similar shape in all three of the surveys of the piers results from minor horizontal positional vari- to date at this site (fig. 28), despite the difference in discharge ances between the surveys (see the “Uncertainty Estimation” (table 7). The rock outcrop on the upstream left (northwest) section). bank showed no signs of substantial change except for minor The difference between the survey on May 24, 2016, and deposition along the toe of the bank along the interface with the previous nonflood survey on October 22, 2010 (fig. 33), the thalweg (fig. 33). As with all difference maps in this also does not indicate substantial bed variation from 2010 report, substantial deposition or scour apparent at the faces to 2016, as indicated by a mean difference of only –0.20 ft of the piers results from minor horizontal positional vari- between the bathymetric surfaces (table 7). The net volume of ances between the surveys (see the “Uncertainty Estimation” cut in the reach from 2010 to 2016 was about 47,000 yd3, and section). Results of Bathymetric and Velocimetric Surveys 43
38 7 50 38 7 55 38 8 05 38 8 10 38 8
0 28 10 0 28 05 0 28 0 27 55 A B E PLANATION Channel-bed elevation, in feet above the North American Vertical Datum of 1988 435 Spur dike
Rock outcrop Rock outcrop 430
425
420
415
0 28 10 Medium dunes Medium dunes Medium dunes 410
38 7 5
405
Railroad 400 bridge pier
Pier 2C 395 FLOW 390
No data Small dunes and ripples Small dunes and ripples Submerged object Pier 3C 0 28 05 $
Vertically averaged velocity, in feet per second Planar bed 0−1 Spur dike 1−2 Railroad Pier 4C bridge pier 2−3 Planar bed 3−4 4−5 5−6 6−7 Survey date May 24, 2016 7−8 Cross section shown Cross section shown Discharge 114,000 cubic feet per second 8−9 0 28 38 7 0 in figure 30 A' B' in figure 31 9−10 Average water-surface elevation 10−11 429.9 feet above the NAVD 88 11−12
Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth 0 27 50 0 27 5 0 27 0 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 29. Bathymetry and vertically averaged velocities of the Missouri River channel near dual bridge structure A4557 on State Highway 370 near St. Louis, Missouri. 44 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
A' 2,550 Pier 5C Pier Cap Piles Column Footing Pedestal 2,450 Seal course 2,350 Seal course
Footing Drilled shafts
Pedestal Cap Column Pier 4C Pier epartment of ransportation, written commun., 2010 2,250 and top of bedroc line from 1 bridge plans Missouri Substructural and superstructural details, approximate ground line, 2,150 Seal course Footing
Drilled shafts
Pedestal Cap Column Pier 3C Pier 2,050 t e e f
n Survey is along cross-section line shown in figure 27, facing downstream i
1,950 . Seal course Footing Drilled shafts
Cap Pedestal
Column 1,850 Pier 2C Pier of left (north) abutment , e c a f
l l i f
m o r 1,750 f Part of bridge shown above Distance 1,650 1,550 Approximate top of bedrock (from core logs) Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey 1,450 Approximate ground line from 1994 bridge plans Average water surface during 2016 survey (429.9 feet above the NAVD 88) Average water surface during 2011 survey (438.2 feet above the NAVD 88) Average water surface during 2010 survey (428.4 feet above the NAVD 88) 1,350 ey features, substructural and superstructural details, surveyed channel bed along the upstream face of bri dge dual bridge K 1,250
Cap Pedestal Column Pier 1C Pier Footing A Figure 30. structure A4557 on State Highway 370 crossing the Missouri River near St. Louis,
1,150
500 475 450 425 400 375 350 325
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E Results of Bathymetric and Velocimetric Surveys 45
B' 2,550 Pier 5C Pier Cap Piles Column Footing Pedestal 2,450 Seal course 2,350 Seal course
Footing Drilled shafts
Pedestal Cap Column Pier 4C Pier epartment of ransportation, written commun., 2010 2,250 and top of bedroc line from 1 bridge plans Missouri Substructural and superstructural details, approximate ground line, 2,150 Seal course Footing
Drilled shafts
Pedestal Cap Column Pier 3C Pier 2,050 t e e f
n Survey is along cross-section line shown in figure 27, facing downstream i
1,950 . Seal course Footing Drilled shafts
Cap Pedestal
Column 1,850 Pier 2C Pier of left (north) abutment , e c a f
l l i f
m o r 1,750 f Part of bridge shown above Distance 1,650 1,550 Approximate top of bedrock (from core logs) Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey 1,450 Approximate ground line from 1994 bridge plans Average water surface during 2016 survey (429.9 feet above the NAVD 88) Average water surface during 2011 survey (438.2 feet above the NAVD 88) Average water surface during 2010 survey (428.4 feet above the NAVD 88) 1,350 ey features, substructural and superstructural details, surveyed channel bed along the upstream face of downstream bri dge dual bridge K
1,250
Cap Pedestal Column Pier 1C Pier Footing Figure 31. structure A4557 on State Highway 370 crossing the Missouri River near St. Louis, B
1,150
500 475 450 425 400 375 350 325
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E
46 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 27 0 0 27 55 FEE 38 8 10 ME ERS 75 250 200 50 150 100 25 50 0 0
0 28 $
38 8 05 30
Spur dike 0 27 5 20 15 10 7 DEPOSITION 5 3 1 38 8
-1 0 28 05 -3 E PLANATION
-5 Rock outcrop Rock
-7 0 27 50
in figure 31
Pier 2C Pier
Pier 3C Pier Pier 4C Pier B dike Spur -10
Cross section shown Change in channel-bed elevation, feet SCOUR B' -15 A . A' -20 -30
-45
object Submerged
38 7 55 in figure 30
Railroad
Railroad
bridge pier bridge bridge pier bridge
Cross section shown
0 28 10 Rock outcrop Rock ifference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A4557 on S tate Highway 370 D
38 7 50
FLOW
Figure 32. near St. Louis, Missouri, on May 24, 2016, and August 2, 2011
Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 28
0 28 10 38 7 5 0 28 05 38 7 0
Results of Bathymetric and Velocimetric Surveys 47
0 27 0 0 27 55 FEE 38 8 10 ME ERS 75 250 200 50 150 100 25 50 0 0
0 28 $
38 8 05 30
Spur dike 0 27 5 20 15 10 7 DEPOSITION 5 3 1 38 8
-1 0 28 05 -3 E PLANATION
-5 Rock outcrop Rock
-7 0 27 50
in figure 31
Pier 2C Pier
Pier 3C Pier Pier 4C Pier B dike Spur -10
Cross section shown Change in channel-bed elevation, feet SCOUR B' -15 A A' -20 . -30
-45
object Submerged
38 7 55 in figure 30
Railroad
Railroad
bridge pier bridge bridge pier bridge
Cross section shown
0 28 10 Rock outcrop Rock ifference between surfaces created from bathymetric surveys of the Missouri River channel near dual bridge structure A4557 on S tate Highway 370 D
38 7 50
FLOW
Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 33. St. Louis, Missouri, on May 24, 2016, and October 22, 2011
0 28
0 28 10 38 7 5 0 28 05 38 7 0 48 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Structure A3047 on U.S. Highway 67 of scour hole at upstream pier/bent face” and “Approximate elevation of bedrock near pier/bent” in table 6). Pier 11 is Structure A3047 (site 27) on U.S. Highway 67 crosses the founded on shafts drilled 15 ft into bedrock, and about 61 ft of Missouri River at RM 8.1, on the northern side of the St. Louis bed material was present between the bottom of the scour hole metropolitan area between Florissant and West Alton, Mo. and bedrock (fig. 36; table 6). Pier 12 is founded on shafts (fig. 1). The site was surveyed on May 27, 2016, and the aver- drilled 26 ft into bedrock, and about 56 ft of bed material was age water-surface elevation near the bridge, determined by present between the bottom of the scour hole and bedrock the RTK GNSS tide solution, was 413.7 ft (table 5). Flow on (fig. 36; table 6). the Missouri River was about 131,000 ft3/s during the survey Scour holes also were observed near the railroad bridge (table 5). piers upstream from structure A3047. The scour hole near the The survey area was about 1,640 ft long and about railroad bridge pier upstream from pier 10 was essentially 1,350 ft wide, extending essentially from bank to bank in the indistinguishable from the channel thalweg (fig. 34); however, main channel (fig. 34). The upstream end of the survey area substantial scour holes were present near the railroad bridge was about 670 ft upstream from the centerline of structure piers upstream from piers 11 and 12. Scour near the upstream A3047 (fig. 34). The approximate channel-bed elevations railroad bridge piers did not seem to have an effect on the ranged from about 381 to 403 ft for most of the surveyed piers of structure A3047 (fig. 34). As in previous surveys area (5th to 95th percentile range of the bathymetric data; (Huizinga, 2011, 2012), the remnant of old bridge piers were table 5; fig. 35). A deep thalweg on the left (northeast) bank observed in the channel downstream from the existing railroad was about 12 to 18 ft deeper than the channel bed in the bridge piers (fig. 34). middle of the channel (fig. 34). Near the spur dike on the The difference between the survey on May 27, 2016, right (southwest) side near the bridge, deposits reached an and the previous survey on August 3, 2011 (fig. 37), indicates elevation of about 404 ft, and behind the longitudinal spur moderate deposition (a mean difference of +0.77 ft between dike on the left (north) side near the bridge, deposits reached the bathymetric surfaces) throughout the reach from 2011 to an elevation of about 406 ft (fig. 34). Numerous small dunes 2016 (table 7). The net volume of cut in the reach from 2011 and ripples were detected throughout the channel; a few to 2016 was about 34,300 yd3, and the net volume of fill was almost-medium dune features with superimposed small about 91,900 yd3, resulting in a net gain of about 57,600 yd3 dunes and ripples were present in the middle of the chan- of sediment between 2011 and 2016. Substantial scour had nel (fig. 34). As in previous surveys (Huizinga, 2011, 2012), been observed between the 2010 and 2011 surveys (Huizinga, stone revetment was present on the upstream right (south- 2012), but ongoing sediment transport processes seem to have west) bank (fig. 34). fully replenished the sediment deposits at this site. There was Small to moderate scour holes were present near the an area of moderate scour near the longitudinal spur dike on main channel piers, except pier 10 near the longitudinal spur the upstream left (northeast) bank (fig. 37). The cross sec- dike on the left (north) side of the channel (fig. 34). Near tions from the two surveys are very similar (fig. 36), and the pier 10, the channel thalweg had an approximate minimum frequency distribution of bed elevations in 2016 was of a channel-bed elevation of about 379 ft (fig. 34; table 6), which similar shape to that in 2011; however, a smaller percentage of is about 32 ft above the bottom of the seal course elevation survey-grid cells were at lower elevations in 2016 than 2011 of 346.50 ft (fig. 36; table 6); however, pier 10 is essentially (fig. 35). The cumulative percentage curves for 2016 and 2011 embedded in the rock of a longitudinal spur dike, which will are remarkably similar (fig. 35). The stone revetment on the limit or prevent scour at this pier. At pier 11, the scour hole right (southwest) bank showed minor deposition in the reach had an approximate minimum channel-bed elevation of about upstream from the bridge (fig. 37). 375 ft, about 12 ft below the average channel bed immediately The difference between the survey on May 27, 2016, and upstream from the pier (fig. 34; table 6). At pier 12, the scour the previous nonflood survey on October 25, 2010 (fig. 38), hole had an approximate minimum channel-bed elevation of indicates minor to moderate scour (a mean difference of about 392 ft, about 6 ft below the average channel bed imme- –1.77 ft between the bathymetric surfaces) throughout the diately upstream from the pier (fig. 34; table 6). reach from 2010 to 2016 (table 7). The net volume of cut in Information from bridge plans indicates that pier 10 is the reach from 2010 to 2016 was about 117,400 yd3, and the founded on shafts drilled 13 ft into bedrock, and about 76 ft net volume of fill was about 13,600 yd3, resulting in a net loss of bed material was present between the channel thalweg and of about 103,800 yd3 of sediment between 2010 and 2016. bedrock at the bridge (table 6), and about 85 ft of bed mate- Most of the scour was observed in the upstream thalweg, rial was present between the bed at the nose of the pier and approaching a balance of scour and deposition as one moves bedrock (fig. 36; difference between “Approximate elevation downstream through the reach (fig. 38). The cross sections
Structure A3047 on U.S. Highway 67. Results of Bathymetric and Velocimetric Surveys 49
0 1 10 0 1 05 0 13 55 0 13 50 0 13 5 0 1
38 50 5 38 50 0 A E PLANATION Channel-bed elevation, in feet above the North American Vertical Datum of 1988
38 50 5 0 1 15 415 Spur dike
Longitudinal spur dike 410
Longitudinal spur dike Old pier Pier 10 Longitudinal spur dike remnant 405
Railroad bridge pier 400 Small dunes amd ripples
395 Small dunes amd ripples
390
Medium dunes with superimposed small dunes 385
Medium dunes with Railroad 38 50 0 superimposed small dunes bridge pier b b' Pier 11 380 d d' FLOW Old pier remnant 375
No data 0 1 20 Longitudinal sections shown in figure 63 Longitudinal sections shown in figure 65
Small dunes amd ripples
Railroad bridge pier c c' Pier 12 Small dunes amd ripples e e' $ Old pier remnant
Spur dike 38 50 35 Survey date May 27, 2016 Stone revetment Discharge 131,000 cubic feet per second
Spur dike Cross section shown A' Average water-surface elevation in figure 36 413.7 feet above the NAVD 88
Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth 38 50 30 38 50 25 38 50 20 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 34. Bathymetric survey of the Missouri River channel near structure A3047 on U.S. Highway 67 near St. Louis, Missouri. 50 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
1.6 100 E PLANATION 3 90 [ft /s, cubic foot per second] 1.4 Frequency distribution 80 2016 survey data; 3 1.2 131,000 ft /s 2011 survey data; 70 225,000 ft3/s 1.0 2010 survey data; 60 87,400 ft3/s Cumulative percentage 0.8 50 2016 survey data; 131,000 ft3/s 2011 survey data; 40 0.6 indicated elevation 225,000 ft3/s 2010 survey data; 30 87,400 ft3/s Percentage of total survey-grid cells 0.4 20 Cumulative percentage of survey-grid cells lower than 0.2 10
0 0 370 375 380 385 390 395 400 405 410 415 420 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 35. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Missouri River near structure A3047 on U.S. Highway 67 near St. Louis, Missouri, on May 27, 2016, compared to previous surveys.
from the two surveys are similar on the left and right sides The vertically averaged velocity vectors indicate mostly of the channel, and indicate scour for most of the channel uniform flow throughout the reach, ranging from about 2 to between piers 10 and 12 (fig. 36). The frequency distribution 8 ft/s (fig. 39). Exceptions to uniform flow include angled of bed elevations was of a similar shape but wider in 2016 flows near the ends of various spur dikes along the banks than in 2010; a greater percentage of survey-grid cells was at and minor turbulence downstream from the piers, which are elevations above 398 ft (fig. 35). slightly skewed to approach flow (fig. 39). Results of Bathymetric and Velocimetric Surveys 51
A'
2,600 Pier 13 Pier Cap Column 2,500 Footing Pedestal Seal course Drilled shafts 2,400 2,300 epartment of ransportation, written commun., 2002
Seal course Footing
Drilled shafts and top of bedroc line from 1 7 bridge plans Missouri Pedestal Cap Column Pier 12 Pier 2,200 Substructural and superstructural details, approximate ground line, 2,100 2,000 t e e f
n Survey is along cross-section line shown in figure 34, facing downstream i
1,900 Average water surface during 2016 survey (413.7 feet above the NAVD 88) Average water surface during 2011 survey (421.8 feet above the NAVD 88) Average water surface during 2010 survey (410.2 feet above the NAVD 88) Channel bed from 2016 multibeam survey Channel bed from 2011 multibeam survey Channel bed from 2010 multibeam survey
1,800 Pier 11 Pier Cap of left (north) abutment , e c Column Footing Pedestal 1,700 a f
l l i Seal course f Drilled shafts
m o r f Part of bridge shown above 1,600 Distance 1,500 scour survey on 11/19/2002 Approximate ground line from Level II 1,400 Approximate top of bedrock (from core logs)
Seal course Footing
Drilled shafts Pedestal Cap Column Pier 10 Pier 1,300 1,200 . 1,100 ey features, substructural and superstructural details, surveyed channel bed of structure A3047 on U.S. Highway 67 crossing the Missouri River K 1974 bridge plans
1,000 Approximate ground line from
Seal course Footing
Drilled shafts Pedestal Cap Column Pier 9 Pier Figure 36. near St. Louis, Missouri A 900
525 500 475 450 425 400 375 350 325 300 275
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E
52 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
38 50 20 38 50 30 38 50 25 FEE ME ERS 0 13 5 75 250 200 50 150 100
25 50
0 0
0 13 50 $ Spur dike Spur 30
20 Longitudinal spur dike spur Longitudinal 15
0 13 55 10 7 DEPOSITION 5 3 1 -1 -3
0 1 E PLANATION
-5
Spur dike Spur 38 50 0 Pier 12 -7 A'
Pier 11 -10
Pier 10 Change in channel-bed elevation, feet
SCOUR Longitudinal spur dike spur Longitudinal -15 A -20 -30
in figure 36 -45
Spur dike Cross section shown
Old pier
remnant .
Old pier 0 1 05 remnant
Old pier
remnant
Railroad
bridge pier
Railroad
Stone revetment
bridge pier
Railroad
bridge pier Longitudinal spur dike spur Longitudinal
0 1 10 ifference between surfaces created from bathymetric surveys of the Missouri River channel near structure A3047 on U.S. Highway 67 St. Louis,
D 38 50 5
FLOW Figure 37. Missouri, on May 27, 2016, and August 3, 2011 Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 1 15 0 1 20
38 50 35 38 50 5 38 50 0
Results of Bathymetric and Velocimetric Surveys 53
38 50 20 38 50 30 38 50 25 FEE ME ERS 0 13 5 75 250 200 50 150 100
25 50
0 0
0 13 50 $ Spur dike Spur 30
20 Longitudinal spur dike spur Longitudinal 15
0 13 55 10 7 DEPOSITION 5 3 1 -1 -3
0 1 E PLANATION
-5
Spur dike Spur 38 50 0 Pier 12 -7 A'
Pier 11 -10
Pier 10 Change in channel-bed elevation, feet
SCOUR Longitudinal spur dike spur Longitudinal -15 A -20 -30
in figure 36 -45
Spur dike Cross section shown
Old pier .
remnant
Old pier 0 1 05 remnant
Old pier
remnant
Railroad
bridge pier
Railroad
Stone revetment
bridge pier
Railroad
bridge pier Longitudinal spur dike spur Longitudinal
0 1 10 ifference between surfaces created from bathymetric surveys of the Missouri River channel near structure A3047 on U.S. Highway 67 St. Louis,
D 38 50 5
FLOW Figure 38. Missouri, on May 27, 2016, and October 25, 2010 Base from Missouri Spatial ata Information Service, 2007 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 1 15 0 1 20
38 50 35 38 50 5 38 50 0 54 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 1 10 0 1 05 0 13 55 0 13 50 0 13 5 0 1
38 50 5 38 50 0 A E PLANATION Channel-bed elevation, in feet above the North American Vertical Datum of 1988
38 50 5 0 1 15 415 Spur dike
Longitudinal spur dike 410
Longitudinal spur dike Old pier Pier 10 Longitudinal spur dike remnant 405
Railroad bridge pier 400 Small dunes amd ripples
395 Small dunes amd ripples
390
Medium dunes with superimposed small dunes 385
Railroad 38 50 0 Medium dunes with bridge pier Pier 11 380 superimposed small dunes FLOW Old pier remnant 375
No data 0 1 20 $ Small dunes amd ripples Vertically averaged velocity, in feet per second Railroad 0−1 bridge pier Pier 12 Small dunes amd ripples 1−2 2−3 Old pier 3−4 remnant 4−5
Spur dike 38 50 35 5−6 6−7 Survey date May 27, 2016 7−8 Stone revetment Discharge 131,000 cubic feet per second 8−9
Spur dike 9−10 Cross section shown A' Average water-surface elevation 10−11 in figure 36 413.7 feet above the NAVD 88 11−12
Base from Missouri Spatial ata Information Service, 2007 0 50 100 150 200 250 FEE Universal ransverse Mercator pro ection, zone 15 orth 38 50 30 38 50 25 38 50 20 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 25 50 75 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 39. Bathymetry and vertically averaged velocities of the Missouri River channel near structure A3047 on U.S. Highway 67 near St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 55
Structure A6500 on Interstate 70 elevation of the bottom of the scour hole on the upstream side of the pier is about 348 ft, about 13 ft below the bottom of the Structure A6500 (site 33) on Interstate 70 crosses the seal course (table 8). Information from bridge plans indicates Mississippi River at RM 181.2, on the eastern side of St. Louis that pier 11 is founded on shafts drilled 22 ft into bedrock, and City, Mo., just north of downtown (fig. 1). The site was about 15 ft of bed material was present between the bottom of surveyed on May 25, 2016, and the average water-surface the scour hole and bedrock (fig. 42; table 8). The undermined elevation near the bridge, determined by the RTK GNSS tide seal course is evident in a point cloud image of the right (west) solution, was 396.6 ft (table 5). Flow on the Mississippi River side of pier 11 (fig. 43); furthermore, the seal course seems to was about 276,000 ft3/s during the survey (table 5). be larger than the footing by about 7 ft on each side (fig. 43), The survey area was about 1,970 ft long and about which is not indicated in the plans (fig. 42). This is true for 1,480 ft wide, extending from bank to bank in the main both piers (appendix 1, fig. 1–6). The approximate ground line channel (fig. 40). The upstream end of the survey area was from the 2010 bridge plans was digitized directly from the about 860 ft upstream from the centerline of structure A6500 (fig. 40). The approximate channel-bed elevations ranged from about 354 to 383 ft for most of the surveyed area (5th to 95th percentile range of the bathymetric data; table 5; fig. 41), except downstream from the right (west) main channel pier, where the overall minimum channel-bed elevation was 334 ft (tables 5, 8; fig. 40). A poorly defined thalweg was pres- ent along the left (east) bank throughout the surveyed area. Numerous small dunes and ripples were detected throughout the channel, and a few medium dune features with superim- posed small dunes and ripples were present in the middle of the channel (fig. 40). As in the previous survey (Huizinga and others, 2010), stone revetment was present on both banks throughout the reach (fig. 40). There was no scour hole near left (east) main channel pier 12 because the pier is surrounded with a riprap blanket (figs. 40, 42; table 8). The top of the riprap blanket is slightly higher than the bottom of the pier seal course elevation of 361.5 ft (fig. 42; table 8). Main channel pier 11 seems to be partly surrounded with mounded riprap, but the top of the riprap pile is below the bottom of the seal course elevation on the downstream side of the pier (fig. 40; table 8). The approximate
Structure A6500 on Interstate 70. 56 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 11 05 0 11 0 10 55 0 10 50 0 10 5 0 10 0 0 10 35 0 10 30 0 10 25 0 10 20 FLOW E PLANATION Channel-bed elevation, in feet 38 38 50 above the North American Vertical Datum of 1988 395
390 Medium dunes with
Stone revetment 385
superimposed small dunes Moored barge Moored Mooring Stone revetment 380 dolphin 375
370 38 38 5 b Longitudinal section A 365 Moored barge Moored shown in figure 64 b' 360
Stone revetment Pier 12 355
350 Longitudinal section Riprap blanket shown in figure 64 c 345 c' 340 Pier 11 Medium dunes with A' superimposed small dunes 335 38 38 0 Cross section shown in figure 42 330
Stone revetment Mooring No data dolphin
Moored barge Moored dock
Moored barge
Stone revetment Sunken barge
Mooring 38 38 35 dolphins $
Stone revetment Survey date May 25, 2016 Mooring dolphins Discharge 276,000 cubic feet per second Moored barge Average water-surface elevation 396.6 feet above the NAVD 88
Base from ational Agricultural Information Program, 2015 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 40. Bathymetric survey of the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 57
3.0 100 E PLANATION 3 90 [ft /s, cubic foot per second]
2.5 Frequency distribution 80 2016 survey data; 276,000 ft3/s 2009 survey data; 70 3 2.0 295,000 ft /s
60 Cumulative percentage 2016 survey data; 276,000 ft3/s 1.5 50 2009 survey data; 295,000 ft3/s 40 indicated elevation 1.0 30 Percentage of total survey-grid cells
20 0.5 Cumulative percentage of survey-grid cells lower than
10
0 0 330 335 340 345 350 355 360 365 370 375 380 385 390 395 400 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 41. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Mississippi River near structure A6500 on Interstate 70 in St. Louis, Missouri, on May 25, 2016, compared to previous surveys.
plans and seems to plot in the correct location relative to the a higher percentage of survey-grid cells at a slightly lower interface between the footings and seal courses according to elevation than in 2009, which mirrors the observed scour in the plans; however, it is uncertain why this line is more than the reach (fig. 41). The discharges and water-surface eleva- 20 ft higher than the two bathymetric survey lines (fig. 42). tions for the 2009 and 2016 surveys were similar (table 7; This site was the subject of a preconstruction habitat fig. 42). assessment, using data collected with the MBMS (Huizinga In the preconstruction survey in 2009, flow was observed and others, 2010). The previous survey gives unique insight to cross from the Illinois (east) side of the river to the Missouri into the effects of the construction of structure A6500 on (west) side through the reach, and generally this was reflected the channel in this reach. The difference between the survey in the vertically averaged velocity vectors for the present on May 25, 2016, and the preconstruction survey on July (2016) survey (fig. 45). Both piers are skewed to approach 7, 2009 (fig. 44), indicates moderate scour (a mean differ- flow, and the scour hole near pier 11 has the typical character- ence of –1.36 ft between the bathymetric surfaces) overall istics of a hole at a skewed pier, being longer on the side with in the reach from 2009 to 2016 (table 7). The net volume of impinging flow and an angled line of deposition on the lee- cut in the reach from 2009 to 2016 was about 336,500 yd3, ward side (figs. 40, 45); however, the 55-ft-wide, square nose and the net volume of fill was about 166,900 yd3, resulting of pier 11, a mild constriction downstream from the pier, and in a net loss of about 169,600 yd3 of sediment between 2009 the additional scour from adjacent mooring dolphins down- and 2016. Large areas of substantial deposition of more than stream likely have exacerbated the scour on the leeward side 10 ft were upstream from the bridge and in the middle of of the pier by increasing local turbulence and pulling sediment the channel downstream from the bridge, as well as along into suspension (figs. 40, 45). A similar situation was observed the right (west) bank downstream from the bridge (fig. 44); at the main channel pylon for structure A7650 in Kansas City however, there was substantial scour along the left (east) bank in 2015 (Huizinga, 2016, fig. 24). throughout the reach and substantial scour of nearly 30 ft at The vertically averaged velocity vectors indicate mostly and downstream from pier 11 (fig. 44). The cross sections uniform flow throughout the reach, ranging from about 2 to from the two surveys show this trend as well; the 2016 survey 8 ft/s (fig. 45). Exceptions to uniform flow include moderate alternates from being above and below the 2009 survey sec- turbulence and flow reversal downstream from the piers which tion (fig. 42). The frequency distribution of bed elevations are skewed to approach flow, and mild turbulence near the was of a similar shape in 2016 compared to 2009 but with various mooring dolphins in the reach (fig. 45). 58 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
) ) ) ) ) ) ) ) b d d e e g e e ( ( ( ( ( ( ( ( 1.97 1.85 1.87 1.79 1.57 1.79 1.28 2.27 1.75 hole (ft/ft) of scour frontal slope Approximate
3 2 2 6 2 6 0 1 ) ) g g b d 11 19 14 12 12 10 10 ( ( (ft) upstream hole from channel bed Depth of scour
5 (ft) 46 15 71 43 28 79 63 60 66 63 56 80 71 60 59 59 Approximate bottom of scour hole and bedrock distance between
(ft) 304 318 287 297 324 356 294 297 297 294 293 295 294 297 297 294 293 pier/bent elevation of Approximate bedrock near
(ft) 362 348 379 340 352 383 374 360 357 364 360 351 374 368 357 363 358 b Approximate pier/bent face hole at upstream elevation of scour
-
a (ft) 350 334 358 340 352 361 373 360 357 360 356 349 374 368 357 353 352 bent b,c hole near pier/ elevation in scour mum channel-bed Approximate mini
— (ft) 361.50 361.50 356.00 339.00 347.00 361.00 353.00 353.00 348.00 344.00 328.00 361.00 353.00 353.00 348.00 344.00 elevation Bottom of seal course
A4936 and A1850; therefore, results shown for this pier are the same both structures. A4936 and 7 7 7 1 1 1 1 1 1 1 1 1 1 1 1 18 22 (ft) into bedrock Penetration
55 55 27 28 30 16 28 36 36 36 36 56 28 36 36 36 36 (ft) Width Foundation information Type Drilled shaft Drilled shaft Drilled shaft Drilled shaft Drilled shaft Footing Piling Piling Piling Piling Piling Piling Piling Piling Piling Piling Piling 5 4 3 2 7 8 9 7 8 9 11 11 11 12 10 12 10 f MoDOT number pier/bent A6500 A1500 A4936 A1850 Results near piers and bents from surveys on the Mississippi River St. Louis, Missouri, May 23–27, 2016. MoDOT number structure
33 34 35 Pier/bent is surrounded by a substantial riprap blanket. by stone revetment along the bank. Scour hole is substantially affected by upstream pier/bent. Scour hole at this pier/bent is substantially affected The point of lowest elevation in the scour hole near bridge pier/bent, not necessarily at upstream face. Indicated elevation is the minimum in area immediately adjacent to riprap blanket around pier/bent. Poorly defined scour hole at this pier/bent. Pier 12 is a single continuous pier that extends between structures Site a b c d e f g (fig. 1) number Table 8. Table Datum of 1988] Vertical American ft, feet; —, not known/applicable; all elevations are in feet above the North Transportation; Missouri Department of [MoDOT, Results of Bathymetric and Velocimetric Surveys 59 A' 2,500 2,400 2,300 2,200 Footing Seal course
Drilled shafts
Tower Shaft Pier 11 Pier 2,100 epartment of ransportation, written commun., 2017 and top of bedroc line from 2010 bridge plans Missouri 2,000 Substructural and superstructural details, approximate ground line, 1,900 t 1,800 e e f
n i
1,700 Survey is along cross-section line shown in figure 40, facing downstream. 1,600 1,500 Channel bed from 2016 multibeam survey Channel bed from 2009 multibeam survey 1,400 1,300 Approximate top of bedrock (from core logs) Approximate ground line from 2010 bridge plans centerline of left (east) main span end pier , Part of bridge shown above
m o r f 1,200 Distance Average water surface during 2016 survey (396.6 feet above the NAVD 88) Average water surface during 2009 survey (398.2 feet above the NAVD 88) 1,100 1,000 900 800 . 700 Footing Seal course
Drilled shafts
Tower Shaft Pier 12 Pier 600 ey features, substructural and superstructural details, surveyed channel bed of structure A6500 on Interstate 70 crossing t he Mississippi K
500 Figure 42. River in St. Louis, Missouri A 400
500 475 450 425 400 375 350 325 300 275
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E 60 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Flow Footing Seal course (about 7 feet wider than the footing)
Approximate bottom of Sonic “shadow” indicating the seal course undermining of the seal course
E PLANATION Elevation of point, in feet above the North American Vertical Datum of 1988
334 340 346 352 358 364 370 376 382 388
Figure 43. Point cloud visualization of the channel bed and right (west) side of main channel pier 11 of structure A6500 on Interstate 70 crossing the Mississippi River in St. Louis, Missouri.
Results of Bathymetric and Velocimetric Surveys 61 0 10 20 FEE ME ERS 500 150 00
100 0 10 25 300 200 50 100
0 0
A 0 10 30
$
Stone revetment Stone
Stone revetment Stone
0 10 35 30 barge revetment Stone
Sunken 20
Pier 12 Riprap blanket Riprap 15 10 7
Mooring dolphins 0 10 0 DEPOSITION 5 3 1
-1
FLOW 0 10 5 -3 E PLANATION -5 -7 . -10 Change in channel-bed elevation, feet SCOUR
-15 0 10 50 -20
Pier 11 -30 -45
dolphin
Mooring
dolphin
Mooring dolphins
Mooring
0 10 55 Stone revetment Stone Stone revetment
A' 0 11
in figure 42
Cross section shown ifference between surfaces created from bathymetric surveys of the Mississippi River channel near structure A6500 on Interstat e 70 in St. Louis, D
0 11 05 Figure 44. Missouri, on May 25, 2016, and before construction, July 7, 2009 Base from ational Agricultural Information Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
38 38 50 38 38 5 38 38 0 38 38 35 62 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 11 05 0 11 0 10 55 0 10 50 0 10 5 0 10 0 0 10 35 0 10 30 0 10 25 0 10 20 FLOW E PLANATION Channel-bed elevation, in feet 38 38 50 above the North American Vertical Datum of 1988 395
390 Medium dunes with
Stone revetment 385
superimposed small dunes Moored barge Moored Mooring Stone revetment 380 dolphin 375
370 38 38 5
Riprap blanket A 365 Moored barge Moored
360
Stone revetment Pier 12 355
350
345
340 Pier 11 Medium dunes with A' superimposed small dunes 335 38 38 0 Cross section shown in figure 42 330
Stone revetment Mooring No data dolphin
Moored barge Moored dock
Moored barge
Stone revetment Sunken $ barge Vertically averaged velocity, in feet per second Mooring 38 38 35 dolphins 0−1 1−2 2−3 3−4 4−5 5−6 6−7
Stone revetment Survey date May 25, 2016 7−8 Mooring dolphins Discharge 276,000 cubic feet per second 8−9 9−10
Moored barge Average water-surface elevation 10−11 396.6 feet above the NAVD 88 11−12
Base from ational Agricultural Information Program, 2015 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 45. Bathymetry and vertically averaged velocities of the Mississippi River channel near structure A6500 on Interstate 70 in St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 63
Structure A1500 on Interstate 55 only about 1 ft above the bottom of the seal course elevation (fig. 48; table 8). Information from bridge plans indicates that Structure A1500 (site 34) on Interstate 55 crosses the pier 4 is founded on shafts drilled 7 ft into bedrock, and about Mississippi River at RM 179.2 on the eastern side St. Louis 43 ft of bed material was present between the bottom of the City, Mo., just east of downtown (fig. 1). The site was sur- scour hole and bedrock (fig. 48; table 8). Similarly, a moderate veyed on May 25, 2016, and the average water-surface scour hole was present near the right main channel pier (pier elevation near the bridge, determined by the RTK GNSS tide 3, fig. 46) with a minimum elevation of about 352 ft, about solution, was 395.7 ft (table 5). Flow on the Mississippi River 12 ft below the average channel bed immediately upstream was about 279,000 ft3/s during the survey (table 5). from the pier (fig. 46; table 8), and about 5 ft above the bottom The survey area was about 1,640 ft long and about of the seal course elevation (fig. 48; table 8). Information from 1,710 ft wide, extending from bank to bank in the main chan- bridge plans indicates that pier 3 also is founded on shafts nel (fig. 46). The upstream end of the survey area was about drilled 7 ft into bedrock, and about 28 ft of bed material was 720 ft upstream from the centerline between structure A1500 present between the bottom of the scour hole and bedrock (fig. 46). The approximate channel-bed elevations ranged (fig. 48; table 8). from about 350 to 382 ft for most of the surveyed area (5th to As with the left bank pier, there was no observable scour 95th percentile range of the bathymetric data; table 5; fig. 47), hole at the right bank pier (pier 2, fig. 46). The right bank is except near pier 4 of structure A1500 and along the toe of the covered with granite paving stone revetment under the bridge left (east) bank (fig. 46). A deep thalweg was along the left and upstream that extends to the toe of the bank and will limit (east) bank throughout the surveyed reach and was about 12 to or prevent scour at this pier. The minimum elevation at the toe 18 ft deeper than the channel bed in the middle of the channel of the right bank near pier 2 was about 361 ft (fig. 46), which (fig. 46). A row of medium dune features with superimposed is about 5 ft above the bottom of the footing elevation of small dunes and ripples were observed in the right (west) side 355.63 ft (fig. 48); however, the toe of the bank is nearly 90 ft of the channel, along with numerous small dunes and ripples to the left from the pier (figs. 46, 48). Information from bridge throughout the rest of the channel (fig. 46). As in the previous plans indicates that pier 2 is founded on footings on bedrock, survey (Huizinga, 2011), the stone revetment was present on and about 27 ft of bed material were present between the bed both banks (fig. 46). and bedrock at the nose of the pier (fig. 48; difference between There was no observed scour hole near the left bank pier “Approximate elevation of scour hole at upstream pier/bent (pier 5, fig. 46). The upper left bank is covered with gravel and face” and “Approximate elevation of bedrock near pier/bent” cobble-sized revetment that seems to extend to the toe of the in table 8). bank and will limit or prevent scour at this pier. The channel The difference between the survey on May 25, 2016, and thalweg at the toe of the left bank had a minimum elevation the previous survey on October 20, 2010 (fig. 49), indicates a of about 350 ft immediately downstream from pier 5 (fig. 46), balance of scour and deposition (a mean difference of –0.38 ft which is about 6 ft below the bottom of the seal course eleva- between the bathymetric surfaces) throughout the reach from tion of 356.00 ft (fig. 48; table 8); however, the thalweg is 2010 to 2016 (table 7). The net volume of cut in the reach more than 100 ft to the right from the pier (figs. 46, 48). Infor- from 2010 to 2016 was about 141,500 yd3, and the net volume mation from bridge plans indicates that pier 5 is founded on of fill was about 105,700 yd3, resulting in a net loss of about shafts drilled 7 ft into bedrock, and about 63 ft of bed material 35,800 yd3 of sediment between 2010 and 2016. There was was present between the channel thalweg and bedrock near the moderate deposition of more than 10 ft in the middle of the bridge (fig. 48), and about 71 ft of bed material was present channel downstream from the bridge (fig. 49); however, sub- between the bed and bedrock at the upstream pier face (fig. 48; stantial scour of as much as 10 ft was observed in the middle table 8). of the upstream channel, and moderate scour was observed A moderate scour hole was present near the left main along the left (east) side of the channel throughout the reach channel pier (pier 4, fig. 46) with a minimum elevation of (fig. 49). The cross section from the 2016 survey alternates about 340 ft, about 14 ft below the average channel bed above and below the 2010 survey; however, the scour holes immediately upstream from the pier (fig. 46; table 8), and at piers 3 and 4 are similar in size and depth (fig. 48). The
Structure A1500 on Interstate 55. 64 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 11 10 0 11 05 0 10 55 0 10 50 0 10 5 0 10 0
0 11
E PLANATION Channel-bed elevation, in feet above the North American FLOW Vertical Datum of 1988 38 37 15 390 Mooring Medium dunes with dolphins 385 Moored barges superimposed small dunes Small dunes and ripples 380 Moored barge Moored 375
370
Stone revetment 365 Longitudinal sections shown in figure 64 360
Stone revetment 355
350 c Mooring b dolphin 345 38 37 10 c' A' b' 340 Cross section shown Pier 2 in figure 48 Pier 3 Pier 4 A Pier 5 335 Mooring dolphin 330
325 Medium dunes with superimposed small dunes Small dunes and ripples 320
Mooring No data dolphin
Stone revetment
Moored barges
Stone revetment 38 37 05 $
Stone revetment
Moored barge
Service dock
Small dunes and ripples Medium dunes with superimposed small dunes Survey date May 25, 2016
Moored barges Discharge 279,000 cubic feet per second Moored
barge Average water-surface elevation 395.7 feet above the NAVD 88 38 37 Base from ational Agricultural Information Program, 2015 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth 38 36 55 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 46. Bathymetric survey of the Mississippi River channel near structure A1500 on Interstate 55 in St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 65
2.50 100 E PLANATION 3 2.25 90 [ft /s, cubic foot per second] Frequency distribution 2.00 80 2016 survey data; 279,000 ft3/s 2010 survey data; 1.75 70 277,000 ft3/s
Cumulative percentage 1.50 60 2016 survey data; 279,000 ft3/s 1.25 50 2010 survey data; 277,000 ft3/s 1.00 40 indicated elevation
0.75 30 Percentage of total survey-grid cells
0.50 20 Cumulative percentage of survey-grid cells lower than
0.25 10
0 0 330 335 340 345 350 355 360 365 370 375 380 385 390 395 400 Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 47. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Mississippi River near structure A1500 on Interstate 55 in St. Louis, Missouri, on May 25, 2016, compared to previous surveys. discharges of the Mississippi River were similar for both except localized areas of deposition (fig. 49). As with all dif- surveys (table 7); however, the frequency distribution of bed ference maps presented in this report, substantial deposition elevations was substantially narrower in 2016 than in 2010 or scour apparent at the faces of the piers results from minor because of a higher minimum channel-bed elevation and horizontal positional variances between the surveys (see the a higher percentage of survey-grid cells at elevations from “Uncertainty Estimation” section). 360 to 364 ft but a substantially lower percentage of survey- The vertically averaged velocity vectors indicate mostly grid cells at elevations between 350 and 356 ft (fig. 47). The uniform flow throughout the reach, ranging from about 3 to scour hole near pier 4 was slightly deeper along the right side 8 ft/s (fig. 50). Exceptions to uniform flow include minor to in 2016 than in 2010, whereas the scour hole near pier 3 was moderate turbulence in several transects, particularly near the slightly shallower in 2016 than in 2010 (fig. 49). The stone mooring dolphins along the left (east) bank, near the moored revetment on the banks showed no signs of substantial change barges, and downstream from the bridge piers (fig. 50). 66 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
A'
2,200
(Abutment) Pier 1 Pier Column Footing 2,100 Drilled shafts 2,000
Footing Pedestal Column Cap 1,900 Pier 2 Pier 1,800 epartment of ransportation, written commun., 200 1,700 and top of bedroc line from 1 63 bridge plans Missouri Substructural and superstructural details, approximate ground line, 1,600 Approximate ground line from bridge plans (1963) 1,500 Footing
Seal course Drilled shafts
Pedestal Column Cap 1,400 Pier 3 Pier t e e f
Survey is along cross-section line shown in figure 46, facing downstream n i 1,300
1,200 1,100 of left (east) abutment , e 1,000 c a f
l l i f
m Average water surface during 2016 survey (395.7 feet above the NAVD 88) Average water surface during 2010 survey (396.5 feet above the NAVD 88) 900 o
r
Channel bed from 2016 multibeam survey Channel bed from 2010 multibeam survey f Pier 4 Pier 800 Distance Cap Column 700 Footing Pedestal Drilled shafts Seal course 600 500 400 Approximate ground line from Level II scour survey (08/13/2010) Approximate top of bedrock (from core logs) Approximate ground line from USGS discharge measurement on 07/13/1993
300 Pedestal Column Cap Pier 5 Pier 200 Footing Seal course
100
Profile showing kKey features, substructural and superstructural details, surveyed channel bed of structure A1500 on Inters tate 55 Drilled shafts (Abutment)
Pier 6 Pier Column Pedestal Footing 0 Figure 48. crossing the Mississippi River in St. Louis, Missouri. A -100
500 475 450 425 400 375 350 325 300 275
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E
Results of Bathymetric and Velocimetric Surveys 67 38 36 55 FEE ME ERS 500 150 00 100 300
0 10 0 200 50 A 100
0 0
$
Stone revetment Stone Pier 5 Pier
0 10 5 30
dolphin dolphin dolphin
Mooring Mooring Mooring 20 15
Mooring dolphins 10 7
0 10 50 DEPOSITION Pier 4 Pier 5 3 1 -1 -3 E PLANATION 0 10 55 -5 -7
FLOW -10 Change in channel-bed elevation, feet
SCOUR Pier 3 Pier -15 -20 -30 0 11 -45
. Stone revetment Stone 2 Pier Stone revetment
0 11 05 ifference between surfaces created from bathymetric surveys of the Mississippi River channel near structure A1500 on Interstat e 55 in St. Louis, A' D
in figure 48
Cross section shown 0 11 10
Figure 49. Missouri, on May 25, 2016, and October 20, 2010 Base from ational Agricultural Information Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
38 37
38 37 10 38 37 15 38 37 05 68 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 11 10 0 11 05 0 10 55 0 10 50 0 10 5 0 10 0
0 11
E PLANATION Channel-bed elevation, in feet above the North American FLOW Vertical Datum of 1988 38 37 15 390 Mooring Medium dunes with dolphins 385 Moored barges superimposed small dunes Small dunes and ripples 380 Moored barge Moored 375
370
Stone revetment 365
360
Stone revetment 355
Mooring 350 dolphin 38 37 10 345 A' 340 Cross section shown Pier 2 in figure 48 Pier 3 Pier 4 A Pier 5 335 Mooring dolphin 330
325 Medium dunes with superimposed small dunes Small dunes and ripples 320
Mooring No data dolphin
Stone revetment
Moored barges Stone revetment $ 38 37 05 Vertically averaged velocity,
Stone revetment in feet per second
Service dock 0−1 1−2 2−3 3−4 Small dunes and ripples 4−5 Medium dunes with 5−6 superimposed small dunes 6−7 Survey date May 25, 2016 7−8 Moored barges Discharge 279,000 cubic feet per second 8−9 Moored barge 9−10 Average water-surface elevation 10−11 395.7 feet above the NAVD 88 11−12 38 37 Base from ational Agricultural Information Program, 2015 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth 38 36 55 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 50. Bathymetry and vertically averaged velocities of the Mississippi River channel near structure A1500 on Interstate 55 in St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 69
Structures A4936 and A1850 on Interstate 255 7 of structures A4936 and A1850 are founded on piles driven to refusal on bedrock at both structures, and about 79 to 80 ft Structures A4936 and A1850 (site 35) are dual bridges of bed material was present between the bottom of the scour on Interstate 255, crossing the Mississippi River at RM 168.8, holes and bedrock (figs. 53, 54; table 8). on the southeastern side of the St. Louis metropolitan area Near pier 8 of upstream structure A4936, the scour hole between Mehlville, Mo., and Columbia, Illinois (fig. 1). had an approximate minimum channel-bed elevation of about The site was surveyed on May 26, 2016, and the average 360 ft, about 11 ft below the average channel bed immediately water-surface elevation near the bridge, determined by the upstream from the pier and 7 ft above the bottom of the seal RTK GNSS tide solution, was 390.5 ft (table 5). Flow on the course elevation of 353.00 ft (figs. 51, 53; table 8). The scour Mississippi River was about 290,000 ft3/s during the survey hole exposed the footing and the top of the seal course at the (table 5). upstream pier (fig. 53), and about 7 ft of channel-bed mate- The survey area was about 1,640 ft long and varied in rial was present above the bottom of the seal course elevation width from about 2,260 ft wide upstream from the L-head dike (table 8). At downstream structure A1850, the scour hole near to about 1,640 ft wide at the downstream end (fig. 51). The pier 8 had an approximate minimum channel-bed elevation of survey area extended from bank to bank in the reach upstream 368 ft, about 6 ft below the average channel bed immediately from the L-head dike, and from the L-head dike to the right upstream (fig. 51); however, the scour hole at the upstream bank in the downstream part of the reach (fig. 51). The pier extended downstream, partly affecting the scour near the upstream end of the survey area was about 720 ft upstream downstream pier (table 8). Nonetheless, the scour hole at the from the centerline of structures A4936 and A1850 at pier 12 downstream pier did not seem to extend below the pedestal (fig. 51). The approximate channel-bed elevations ranged (fig. 54), and about 15 ft of channel-bed material was present from about 350 to 375 ft for most of the surveyed area (5th to above the bottom of the seal course elevation (table 8). Infor- 95th percentile range of the bathymetric data; table 5; fig. 52), mation from bridge plans indicates that pier 8 of structures except near the L-head dike (fig. 51). A shallow thalweg was A4936 and A1850 are founded on piles driven to refusal on present along the right (west) bank throughout the reach and bedrock at both structures, and about 63 to 71 ft of bed mate- was about 3 to 7 ft deeper than the channel bed in the middle rial was present between the bottom of the scour holes and of the channel (fig. 51). The channel and thalweg deepened bedrock (figs. 53, 54; table 8). downstream from the bridges (fig. 51), likely because of Near pier 9 of upstream structure A4936, the scour hole the contraction of the channel caused by the L-head dike on had an approximate minimum channel-bed elevation of about the left bank. On the upstream left (northeast) side, depos- 357 ft, about 10 ft below the average channel bed immediately its reached an elevation of about 377 ft (fig. 51). A line of upstream from the pier, and about 4 ft above the bottom of medium dune features were detected along the toe of the right the seal course elevation of 353.00 ft (figs. 51, 53; table 8). (west) bank, and numerous smaller dunes and ripples were At downstream structure A1850, the scour hole near pier 9 present throughout the survey reach (fig. 51). A localized deep had a minimum channel-bed elevation of 357 ft, also about scour hole at the side of the L-head dike on the left bank had 10 ft below the average channel bed immediately upstream, an approximate minimum channel-bed elevation of about and about 4 ft above the bottom of the seal course elevation 322 ft (fig. 51; table 5). As in previous surveys (Huizinga, of 353.00 ft (figs. 51, 54; table 8). Information from bridge 2011; Rydlund, 2009), a rock outcrop was present on the right plans indicates that pier 9 of structures A4936 and A1850 are (west) bank throughout the reach (fig. 51). founded on piles driven to refusal on bedrock at both struc- Substantial scour holes were present near piers 7, 8, and tures, and about 60 ft of bed material was present between the 9 of upstream structure A4936; and moderate scour holes were bottom of the scour holes and bedrock (figs. 53, 54; table 8). present near piers 7, 8, and 9 of downstream structure A1850 Scour holes were not observed upstream from piers 10 (fig. 51). Near pier 7 of upstream structure A4936, the scour and 11 of either structure A4936 or A1850 (fig. 51); in fact, the hole had a minimum elevation of about 373 ft, about 12 ft surveyed channel bed seems to be aggraded near these piers below the average channel bed immediately upstream from the (figs. 53, 54), which indicates riprap or some other scour-resis- pier and 12 ft above the bottom of the seal course elevation tant material has been piled near the upstream faces of these of 361.00 ft (figs. 51, 53; table 8). The scour hole extended piers; however, the side edges and downstream corners of the downstream around pier 7 of downstream structure A1850 footings are apparent at pier 11 of both structures (appendix 1, (fig. 51) and had an approximate minimum channel-bed eleva- figs. 1–9C, 1–9D), and a local scour hole with an approximate tion of 374 ft near that pier (fig. 54; table 8). The scour holes minimum channel-bed elevation of 352 ft was present near did not extend below the bottom of the pedestals at either pier the downstream left corner of pier 11 of downstream structure (figs. 53, 54). Information from bridge plans indicates that pier A1850 (fig. 51; table 8). The remnant of an old bridge pier was observed between piers 9 and 10 of downstream structure A1850 (figs. 51, 54). Information from bridge plans indicates that piers 10 and 11 are founded on piles driven to refusal on
Structures A4936 and A1850 on Interstate 255. 70 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 16 5 0 16 0 0 16 35 0 16 30 0 16 25 0 16 20 0 16 15
38 2 20 38 2 15 E PLANATION Channel-bed elevation, in feet above the North American FLOW Vertical Datum of 1988 395
390 Medium dunes Small dunes and ripples 385 380
Rock outcrop 375 370 365 38 2 20 Small dunes and ripples Longitudinal sections 360 shown in figure 64 355 Longitudinal section f e d c 350 shown in figure 64 f' A4936 A4936 A4936 A4936 A4936 Pier 11 Pier 10 Pier 9 Pier 8 Pier 7 Cross section shown A' e' d' c' A 345 in figure 53 340 Pier 13 Pier 12 A1850 h g Cross section shown Pier 10 h' g' 335 in figure 54 B' A1850 A1850 A1850 A1850 B 0 16 50 Medium dunes Pier 11 Pier 9 Pier 8 Pier 7 330
Remnant of 325 Mooring old bridge pier 320 dolphins
Rock outcrop No data 38 2 15
L-head dike
Mooring $ dolphins
Medium dunes Small dunes and ripples L-head dike
Rock outcrop
Survey date May 26, 2016 38 2 10 Discharge 290,000 cubic feet per second Average water-surface elevation 390.5 feet above the NAVD 88
Base from ational Agricultural Information Program, 2015 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth 38 2 05 38 2 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 51. Bathymetric survey of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 71
4.0 100 E PLANATION [ft3/s, cubic foot per second] 90 3.5 Frequency distribution 80 2016 survey data; 290,000 ft3/s 3.0 2010 survey data; 70 288,000 ft3/s July 2009 survey data; 2.5 3 60 271,000 ft /s May 2009 survey data; 424,000 ft3/s 2.0 50 2008 survey data; 215,000 ft3/s 40 1.5 indicated elevation Cumulative percentage 2016 survey data; 30 290,000 ft3/s Percentage of total survey-grid cells 1.0 2010 survey data; 3 20 288,000 ft /s July 2009 survey data; Cumulative percentage of survey-grid cells lower than 0.5 271,000 ft3/s 10 May 2009 survey data; 424,000 ft3/s 0 0 2008 survey data; 320 325 330 335 340 345 350 355 360 365 370 375 380 385 390 395 215,000 ft3/s Elevation, in feet above the North American Vertical Datum of 1988 (NAVD 88)
Figure 52. Frequency distribution of bed elevations for bathymetric survey-grid cells on the Mississippi River near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri, on May 26, 2016, compared to previous surveys. bedrock at both structures, and about 59 to 66 ft of bed mate- 5 to 6 ft/s in the current (2016) survey (fig. 55), which are of rial was present between the approximate minimum channel- sufficiently high magnitude to create a moderate to substantial bed elevation near each pier and bedrock (figs. 53, 54; table 8). scour hole in a sand-bed channel like the Mississippi River, A minor to moderate scour hole was present upstream dependent upon the cross-sectional size and shape of the from pier 12 with a minimum elevation of about 349 ft, about pier (Richardson and Davis, 2001). Furthermore, during the 6 ft below the average channel bed immediately upstream survey on May 12–13, 2009, completed as part of the fixed from the pier, but 21 ft above the bottom of the seal course scour-monitor study at this site (Rydlund, 2009; full bathym- elevation of 328.00 ft (figs. 51, 53, 54; table 8). Information etry shown in Huizinga and others [2010] and included with from bridge plans indicates that pier 12 is founded on piles the data from this report), flow conditions were such that flow driven to refusal on bedrock, and about 56 ft of bed material was over the L-head dike (Huizinga and others, 2010, fig. 11). was present between the bottom of the scour hole and bedrock Although velocity data were not collected during that survey, (figs. 53, 54; table 8). the researchers recollect experiencing substantial veloci- The vertically averaged velocity vectors indicate mostly ties around piers 7 through 9 of a magnitude similar to those uniform flow throughout the channel, ranging from about observed further to the right in the channel when there was 2 to 9 ft/s (fig. 55). Flow was angled to the right (west) in the flow over the L-head dike. transects immediately upstream and adjacent to the L-head As indicated in the previous paragraph, real-time scour dike because of the constricting effect of the dike (fig. 55). monitoring of the scour hole at pier 12 happened at this site Exceptions to uniform conditions include moderate turbulence in 2008–2009 using fixed, single-beam acoustic transduc- observed in all the transects, and substantial velocity gradi- ers attached to the upstream and downstream nose of pier 12 ents and flow reversal in the area adjacent to the L-head dike (Rydlund, 2009). Three bathymetric surveys of the area were (fig. 55). The piers generally seem to be aligned with flow completed at a variety of flow conditions as part of that study (fig. 55). for verification of data received from the fixed transducers; Given the generally low velocities observed along the furthermore, this site was part of the previous study of sites left (east) bank in the upstream part of the reach, which obvi- on the Missouri and Mississippi Rivers near St. Louis (Huiz- ously results in deposition in the area along the upstream inga, 2011). As in the preceding discussions at each site in left bank, the size of the scour holes around piers 7 through the St. Louis area, the differences between the current (2016) 9—and particularly near pier 7—perhaps are unexpected; survey at this site and the previous surveys will be examined however, velocities upstream from piers 8 and 9 were around and discussed in reverse chronological order. 72 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO A' 3,700
Pede- stal
Footing Column Cap Pier 13 Pier 3,600 3,500 3,400 3,300 epartment of ransportation, written commun., 2002 3,200 and top of bedroc line from 1 77 bridge plans Missouri scour survey on 11/19/2002 Substructural and superstructural details, approximate ground line, 3,100 Approximate ground line from Level II 3,000 Channel bed from 2016 multibeam survey Channel bed from 2010 multibeam survey Channel bed from July 2009 multibeam survey Channel bed from May 2009 multibeam survey Channel bed from 2008 multibeam survey Approximate top of bedrock (from core logs) 2,900 t e e f
Average water surface during 2016 survey (390.5 feet above the NAVD 88) Average water surface during 2010 survey (391.6 feet above the NAVD 88) Average water surface during July 2009 survey (390.3 feet above the NAVD 88) Average water surface during May 2009 survey (403.7 feet above the NAVD 88) Average water surface during 2008 survey (383.8 feet above the NAVD 88) Survey is along cross-section line shown in figure 51, facing downstream n
i 2,800
Pier 12 Pier 2,700 2,600 Cap Piles Footing Column Pedestal Seal course
2,500 Pier 11 Pier fill face of left (east) abutment ,
m o 2,400 r f Part of bridge shown above 2,300
Distance Pier 10 Pier 2,200 2,100 Cap Piles Footing Column Pedestal Seal course
2,000 Pier 9 Pier 1,900
1,800 Pier 8 Pier . 1,700 ey features, substructural and superstructural details, surveyed channel bed of structure A4936 on Interstate 255 crossing the Mississippi River 1,600 Cap Piles K Column Footing Pedestal Seal course
bridge plans line from 1977
Approximate ground 1,500 Pier 7 Pier A Figure 53. near St. Louis, Missouri 1,400
500 475 450 425 400 375 350 325 300 275
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E Results of Bathymetric and Velocimetric Surveys 73 B' 3,700
Pede- stal
Footing Column Cap Pier 13 Pier 3,600 3,500 3,400 3,300 epartment of ransportation, written commun., 2002 3,200 and top of bedroc line from 1 77 bridge plans Missouri scour survey on 11/19/2002 Substructural and superstructural details, approximate ground line, 3,100 Approximate ground line from Level II 3,000 Channel bed from 2016 multibeam survey Channel bed from 2010 multibeam survey Channel bed from July 2009 multibeam survey Channel bed from May 2009 multibeam survey Channel bed from 2008 multibeam survey Approximate top of bedrock (from core logs) 2,900 t e e f
Average water surface during 2016 survey (390.5 feet above the NAVD 88) Average water surface during 2010 survey (391.6 feet above the NAVD 88) Average water surface during July 2009 survey (390.3 feet above the NAVD 88) Average water surface during May 2009 survey (403.7 feet above the NAVD 88) Average water surface during 2008 survey (383.8 feet above the NAVD 88) Survey is along cross-section line shown in figure 51, facing downstream n
i 2,800
Pier 12 Pier 2,700 2,600 Cap Piles Footing Column Pedestal Seal course
2,500 Pier 11 Pier fill face of left (east) abutment ,
m o 2,400 r f Part of bridge shown above 2,300
Distance Pier 10 Pier 2,200 2,100 Cap Piles Footing Column bridge pier Pedestal Seal course Remnant of old
2,000 Pier 9 Pier 1,900
1,800 Pier 8 Pier . 1,700 ey features, substructural and superstructural details, surveyed channel bed of structure A1850 on Interstate 255 crossing the Mississippi River 1,600 K Cap Piles Column Footing Pedestal
Seal course bridge plans line from 1977
Approximate ground 1,500 Pier 7 Pier Figure 54. near St. Louis, Missouri B 1,400
500 475 450 425 400 375 350 325 300 275
t above the North American Vertical Datum of 1988 (NAVD 88) (NAVD 1988 of Datum Vertical American North the above t e e f n i , n o i t a v e l E 74 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
0 16 5 0 16 0 0 16 35 0 16 30 0 16 25 0 16 20 0 16 15
38 2 20 38 2 15 E PLANATION Channel-bed elevation, in feet above the North American FLOW Vertical Datum of 1988 395
390 Medium dunes Small dunes and ripples 385 380
Rock outcrop 375 370 365 38 2 20 Small dunes and ripples 360 355 350 A4936 A4936 A4936 A4936 A4936 Pier 11 Pier 10 Pier 9 Pier 8 Pier 7 Cross section shown A' A 345 in figure 53 340 Pier 13 Pier 12 A1850 Cross section shown Pier 10 335 in figure 54 B' A1850 A1850 A1850 A1850 B 0 16 50 Medium dunes Pier 11 Pier 9 Pier 8 Pier 7 330
Remnant of 325 Mooring old bridge pier 320 dolphins
Rock outcrop No data 38 2 15
L-head dike
Mooring $ dolphins Vertically averaged velocity, in feet per second Medium dunes Small dunes and ripples L-head dike 0−1 1−2 2−3 3−4 4−5
Rock outcrop 5−6 6−7 Survey date May 26, 2016 38 2 10 7−8 Discharge 290,000 cubic feet per second 8−9 9−10 Average water-surface elevation 10−11 390.5 feet above the NAVD 88 11−12
Base from ational Agricultural Information Program, 2015 0 100 200 300 00 500 FEE Universal ransverse Mercator pro ection, zone 15 orth 38 2 05 38 2 Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 0 50 100 150 ME ERS ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
Figure 55. Bathymetry and vertically averaged velocities of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 near St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 75
The difference between the survey on May 26, 2016, and bank in all the surveys (figs. 53, 54). The frequency distribu- the previous survey on October 19, 2010 (fig. 56), indicates an tion of bed elevations was of a similar shape in 2016 com- approximate balance of scour and deposition (a mean differ- pared to July 2009, albeit with a lower percentage of survey- ence of +0.77 ft between the bathymetric surfaces) throughout grid cells at elevations between 358 and 366 ft and a higher the reach from 2010 to 2016 (table 7). The net volume of cut percentage of survey-grid cells at elevations between 366 and in the reach from 2010 to 2016 was about 53,800 yd3, and 380 ft than in July 2009 (fig. 52). The rock outcrops on the the net volume of fill was about 140,500 yd3, resulting in a right (west) bank seem to have experienced localized deposi- net gain of about 86,700 yd3 of sediment between 2010 and tion, as did the structure of the L-head dike (fig. 57), but it is 2016. There was moderate to substantial deposition of more uncertain how much of this apparent difference is a function than 10 ft in the scour holes upstream from piers 8 and 9 of of positional variations between the surveys. Position infor- upstream structure A4936 between 2010 and 2016 (fig. 56). mation for surveys before 2010 were not processed through There was a general area of moderate deposition in the left POS-Pac™ MMS™, and therefore have more questionable (east) side of the channel throughout the reach, an area of positional accuracy, particularly near the bridges where GNSS moderate scour on the far left (east) side along the bank, signal might be lost. As with all difference maps presented in and a balance of minor to moderate scour and deposition in this report, substantial deposition or scour apparent at the faces the rest of the channel between piers 12 and 13 on the right of the piers likely results from minor horizontal positional (west) bank (fig. 56). The cross sections from the 2016 survey variances between the surveys (see the “Uncertainty Estima- compared to the 2010 survey show the pattern of deposition, tion” section). particularly between piers 8 and 11, whereas the section lines The difference between the survey on May 26, 2016, and are similar to one another between pier 12 and pier 13 on the survey on May 12–13, 2009 (fig. 58), also indicates an the right bank in all the surveys (figs. 53, 54). The frequency approximate balance of scour and deposition (a mean differ- distribution of bed elevations was of a similar shape in 2016 ence of –0.17 ft between the bathymetric surfaces) throughout compared to 2010; however, a lower percentage of survey-grid the reach from May 2009 to 2016 (table 7). The discharge cells were at elevations between 352 and 357 ft, and a higher during the May 2009 survey was 424,000 ft3/s (table 7), which percentage of survey-grid cells were at elevations between is close to the 50-percent annual exceedance probability 365 and 375 ft than in 2010 (fig. 52). The rock outcrops on the (2-year recurrence interval) flood discharge of 450,000 ft3/s right (west) bank seem to have experienced localized deposi- for the streamgage at St. Louis (U.S. Army Corps of Engi- tion, whereas the structure of the L-head dike appears to have neers, 2004a, table D–28). However, the net volume of cut experienced minor scour (fig. 56), but this may be partly a in the reach from May 2009 to 2016 was about 131,800 yd3, function of positional variations between the surveys. As and the net volume of fill was about 111,500 yd3, resulting in with all difference maps presented in this report, substantial a net loss of only about 20,300 yd3 of sediment between May deposition or scour apparent at the faces of the piers likely 2009 and 2016. There was moderate deposition of over 6 ft results from minor horizontal positional variances between the in the scour holes upstream from piers 8 and 9 of upstream surveys (see the “Uncertainty Estimation” section). structure A4936, and moderate scour near pier 10 as well as The difference between the survey on May 26, 2016, and downstream from pier 12 of both structures A4936 and A1850 the survey on July 8, 2009 (fig. 57), also indicates an approxi- between May 2009 and 2016 (fig. 58). There was a general mate balance of scour and deposition (a mean difference of area of minor to moderate deposition in the left (east) side +0.51 ft between the bathymetric surfaces) throughout the of the channel upstream from the bridges and in the middle reach from July 2009 to 2016 (table 7). The net volume of cut of the channel downstream from the bridges, with an area in the reach from July 2009 to 2016 was about 97,400 yd3, and of moderate scour in the middle to right side of the channel the net volume of fill was about 152,200 yd3, resulting in a net upstream from the bridge and between piers 11 and 12, and gain of about 54,800 yd3 of sediment between July 2009 and a balance of minor to moderate scour and deposition along 2016. There was moderate to substantial deposition of more the right (west) bank as in the other surveys (fig. 58). There than 10 ft in the scour holes upstream from piers 8 and 9 of was substantial scour of over 15 ft along the left (west) bank, upstream structure A4936, and moderate scour near pier 10, and in the scour hole created by flow around the L-head dike as well as downstream from pier 12 of both structures A4936 (fig. 58). The cross sections from the 2016 survey compared and A1850 between July 2009 and 2016 (fig. 57). There was to the May 2009 survey show the similarities of the sections, a general area of moderate deposition in the left (east) side except between piers 7 and 8 and between piers 11 and 12 of the channel at and upstream from the bridges, an area of (figs. 53, 54). The frequency distribution of bed elevations moderate scour in the middle of the channel near the upstream was of a remarkably similar shape in 2016 compared to May and downstream ends of the reach, and a balance of minor 2009, albeit with a lower percentage of survey-grid cells at to moderate scour and deposition along the right (west) bank elevations between 358 and 366 ft and a higher percentage of (fig. 57). The cross sections from the 2016 survey compared to survey-grid cells at elevations between 366 and 369 ft than in the July 2009 survey show the pattern of deposition, particu- May 2009 (fig. 52). The frequency distribution and cumula- larly between piers 10 and 12, whereas the section lines are tive percentage curve of the 2016 survey are most similar to similar to one another between pier 12 and pier 13 on the right the May 2009 curves, despite the difference of discharge of 76 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO FEE ME ERS B A 500 150
00
Pier 7 Pier
A1850
Pier 7 Pier A4936 100
300 38 2 15
0 16 15 200
50
Pier 8 Pier
A1850
Pier 8 Pier A4936 100
0 0
$
L-head dike L-head
38 2
Pier 9 Pier
A1850
Pier 9 Pier A4936
L-head dike 0 16 20
45
Remnant of Remnant old bridge pier bridge old
30
A1850
A4936
Pier 10 Pier Pier 10 Pier 20 15 10
7
A1850 A4936
DEPOSITION
Pier 11 Pier Pier 11 Pier 0 16 25 5 3
1 Pier 12 Pier -1 -3 E PLANATION
0 16 30 -5
FLOW
-7 38 2 20 Change in channel-bed elevation, feet -10 SCOUR -15 . -20 -30
0 16 35 -45
38 2 05
dolphins
Mooring dolphins Mooring Rock outcrop
Pier 13 Pier Rock outcrop
Rock outcrop 0 16 0 A' B' ifference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 D
in figure 53 in figure 54
Cross section shown Cross section shown
0 16 5 Figure 56. St. Louis, Missouri, on May 26, 2016, and October 19, 2010 Base from ational Agricultural Information Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 16 50
38 2 15 38 2 20 38 2 10 Results of Bathymetric and Velocimetric Surveys 77 FEE ME ERS B A 500 150
00
Pier 7 Pier
A1850
Pier 7 Pier A4936 100
300 38 2 15
0 16 15 200
50
Pier 8 Pier
A1850
Pier 8 Pier
36 49 A 100
0 0
$
L-head dike L-head
38 2
Pier 9 Pier
A1850
Pier 9 Pier A4936
L-head dike 0 16 20
45
Remnant of Remnant old bridge pier bridge old
30
A1850
A4936
Pier 10 Pier Pier 10 Pier 20 15 10
7
A1850 A4936
DEPOSITION
Pier 11 Pier Pier 11 Pier 0 16 25 5 3
1 Pier 12 Pier -1 -3 E PLANATION
0 16 30 -5
FLOW
-7 38 2 20 Change in channel-bed elevation, feet -10 SCOUR -15 . -20 -30
0 16 35 -45
38 2 05
dolphins
Mooring dolphins Mooring Rock outcrop
Pier 13 Pier Rock outcrop
Rock outcrop 0 16 0 A' B' ifference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 D
in figure 53 in figure 54
Cross section shown Cross section shown
0 16 5 Figure 57. near St. Louis, Missouri, on May 26, 2016, and July 8, 2009 Base from ational Agricultural Information Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 16 50
38 2 15 38 2 20 38 2 10 78 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO FEE ME ERS B A 500 150
00
Pier 7 Pier
A1850
Pier 7 Pier A4936 100
300 38 2 15
0 16 15 200
50
Pier 8 Pier
A1850
Pier 8 Pier A4936 100
0 0
$
L-head dike L-head
38 2
Pier 9 Pier
A1850
Pier 9 Pier A4936
L-head dike 0 16 20
45
Remnant of Remnant old bridge pier bridge old
30
A1850
A4936
Pier 10 Pier Pier 10 Pier 20 15 10
7
A1850 A4936
DEPOSITION
Pier 11 Pier Pier 11 Pier 0 16 25 5 3
1 Pier 12 Pier -1 -3 E PLANATION
0 16 30 -5
FLOW
-7 38 2 20 Change in channel-bed elevation, feet -10 SCOUR -15 . -20 -30
0 16 35 -45
38 2 05
dolphins
Mooring dolphins Mooring Rock outcrop
Pier 13 Pier Rock outcrop
Rock outcrop 0 16 0 A' B' ifference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 D
in figure 53 in figure 54
Cross section shown Cross section shown
0 16 5 Figure 58. St. Louis, Missouri, on May 26, 2016, and 12–13, 2009 Base from ational Agricultural Information Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88
0 16 50
38 2 15 38 2 20 38 2 10 Results of Bathymetric and Velocimetric Surveys 79
134,000 ft3/s between May 2009 and 2016 (fig. 52; table 7). horizontal positional variances between the surveys (see the The rock outcrops on the right (west) bank appear to have “Uncertainty Estimation” section), particularly with data near experienced localized scour, as did the structure of the L-head the bridge before 2010. dike (fig. 58), but it is presumed much of this apparent differ- ence is a function of positional variations between the surveys. As mentioned in the previous paragraph, position information General Findings and Implications for surveys before 2010 were not processed through POS- Several of the findings at each surveyed bridge were Pac™ MMS™, and therefore have more questionable posi- common to all the bridges, and some findings were evident tional accuracy, particularly near the bridges where GNSS sig- only when results of the surveys were examined as a set. nal might be lost. As with all difference maps presented in this These general findings are of benefit in the assessment of report, substantial deposition or scour apparent at the faces of scour at the surveyed bridges, as well as other bridges close by the piers likely results from minor horizontal positional vari- or in similar settings. ances between the surveys (see the “Uncertainty Estimation” section), particularly with data near the bridge before 2010. The difference between the survey on May 26, 2016, and Effects of Low to Moderate Flooding Compared the survey on October 2–3, 2008 (fig. 59), also indicates an to Previous Surveys approximate balance of scour and deposition (a mean differ- ence of +0.53 ft between the bathymetric surfaces) through- Richardson and Davis (2001) separate long-term aggra- out the reach from 2008 to 2016 (table 7). The net volume dation and degradation of a channel from the contraction of cut in the reach from 2008 to 2016 was about 70,300 yd3, and local scour that happens at a bridge site during floods. and the net volume of fill was about 126,400 yd3, resulting Contraction scour is the general change in the channel-bed in a net gain of about 56,100 yd3 of sediment between 2008 elevation across a bridge opening resulting from the passage and 2016. There was moderate deposition of over 8 ft in the of a flood through a constriction, where more material is in scour hole upstream from pier 8 of upstream structure A4936, suspension and transport. Local scour is the localized erosion moderate to substantial deposition of over 10 ft in the scour of material caused by flow vortex action that forms near bridge hole upstream from pier 9 of upstream structure A4936, and piers and abutments. Although all the scour processes (long moderate scour downstream from piers 10 and 12 of both term, contraction, and local scour) continually are at work, structures A4936 and A1850 between 2008 and 2016 (fig. 59). contraction and local scour generally are cyclic for the live- There was a general area of minor to moderate scour in the bed scour typically observed in alluvial channels and generally middle of the channel throughout the reach, whereas there was result in a decrease and subsequent increase of the channel- minor to moderate deposition on both sides of the channel bed elevation during a flood. (fig. 59). There was substantial scour of more than 20 ft in the Because of the myriad number and interactions of factors scour hole created by flow around the L-head dike (fig. 59). affecting sediment transport conditions and the resultant bed The cross sections from the 2008 survey were similar to the configuration, it is recognized as simplistic to assume that the July 2009 and 2010 surveys, so the comparison to the 2016 configuration and size of bed forms observed during the cur- sections show the pattern of deposition, particularly between rent (2016) surveys near St. Louis (fig. 1) are dependent only piers 10 and 12, whereas the section lines are similar to one upon the instantaneous discharge at a given site. While it is another between pier 12 and pier 13 on the right bank in all beyond the scope of the current (2016) study to examine all of the surveys (figs. 53, 54). As in all the surveys at this site, the antecedent conditions that created the observed channel- the frequency distribution of bed elevations was of a similar bed configuration, the following discussion attempts to draw shape in 2016 compared to 2008, albeit with a lower per- conclusions based on the conditions observed at each site dur- centage of survey-grid cells at elevations between 352 and ing the current (2016) and previous surveys. 356 ft and between 358 and 365 ft, and a higher percentage A comparison of the dune sizes at the various sites is of survey-grid cells at elevations between 365 and 385 ft than indicative of the different flow regimes between 2011 and in 2008 (fig. 52). The rock outcrops on the right (west) bank 2016 at the Missouri River sites (sites 23 to 27). Whereas appear to have experienced localized deposition, whereas many of the surveys in 2011 had medium to large dune the structure of the L-head dike appears to have experienced features, the 2016 surveys were filled throughout with mostly localized moderate scour (fig. 59), but it is presumed much of small to medium dune features and ripples (figs. 6, 13, 20, 27, this apparent difference is a function of positional variations and 34). The largest dune features in the 2016 surveys were between the surveys. As mentioned in the previous paragraph, observed at dual bridge structure A5585 (site 24, fig. 13). The position information for surveys before 2010 were not pro- smaller size and amplitude of the dune features compared to cessed through POS-Pac™ MMS™, and therefore have more 2011 indicates less bed-material and bedload transport because questionable positional accuracy, particularly near the bridges of the lower flow values (Simons and others, 1965). where GNSS signal might be lost. As with all difference Many flood durations on the Missouri and Mississippi maps presented in this report, substantial deposition or scour Rivers near St. Louis can be measured in days to weeks apparent at the faces of the piers likely results from minor because of the large upstream contributing drainage area; 80 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO FEE ME ERS B A 500 150
00
Pier 7 Pier
A1850
Pier 7 Pier A4936 100
300 38 2 15
0 16 15 200
50
Pier 8 Pier
A1850
Pier 8 Pier
4936 A 100
0 0
$
L-head dike L-head
38 2
Pier 9 Pier
A1850
Pier 9 Pier A4936
L-head dike 0 16 20
45
Remnant of Remnant old bridge pier bridge old
30
A1850
A4936
Pier 10 Pier Pier 10 Pier 20 15 10
7
A1850 A4936
DEPOSITION
Pier 11 Pier Pier 11 Pier 0 16 25 5 3 1 -1 -3
E PLANATION Pier 12 Pier
0 16 30 -5
FLOW
-7 38 2 20 Change in channel-bed elevation, feet -10 SCOUR -15 . -20 -30
0 16 35 -45
38 2 05
dolphins
Mooring dolphins Mooring Rock outcrop
Pier 13 Pier Rock outcrop
Rock outcrop 0 16 0 A' B' ifference between surfaces created from bathymetric surveys of the Mississippi River channel near structures A4936 and A1850 on Interstate 255 D
in figure 53 in figure 54
Cross section shown Cross section shown
0 16 5 Base from ational Agricultural Information Program, 2015 Universal ransverse Mercator pro ection, zone 15 orth Horizontal coordinate information referenced to the orth American atum of 1 83 A 83 ertical coordinate information referenced to the orth American ertical atum of 1 88 A 88 Figure 59. St. Louis, Missouri, on May 26, 2016, and October 2–3, 2008
0 16 50
38 2 15 38 2 20 38 2 10 Results of Bathymetric and Velocimetric Surveys 81 however, as described in the “Description of Flow Conditions” and scour. At dual bridge structure A4557, the feature may be section earlier in this report, most of the surveys in this study a combination of the constriction at structures A3292/L0561 happened during a trough between flood rises during gener- (site 25) upstream (fig. 20) and being near the downstream ally higher late-spring flows (fig. 2). The fixed scour monitors end of the relatively straight reach of river between structures on structures L0550 and A4497 at Jefferson City, Mo., about A3292/L0561 and dual bridge structure A4557 (fig. 1); sedi- 145 river miles upstream from the St. Louis metropolitan area, ment may be pulled into suspension in the constriction and discussed in Huizinga (2014) indicate that many of the local unable to be deposited near dual bridge structure A4557 until scour holes observed at the upstream nose of the piers at that the next river bend downstream (fig. 1). Deposition upstream site did not fill in rapidly after the recession of a flood (Huiz- from the constriction at structures A3292/L0561 also may inga, 2014, fig. 35); nevertheless, flood recession generally explain the trend in the average channel-bed elevations seen at leads to deposition rather than scour. Examining results based dual bridge structures A5585 (site 24; fig. 60). Unfortunately, purely on instantaneous discharge and ignoring effects from there are no other bridges near structure A3047 (site 27) from antecedent flow conditions, it might be reasonable to assume which any conclusions about scour or deposition in the vicin- that the scour holes near the piers and the general scour ity of A3047 can be drawn. observed under the bridge crossings might be of an equal Flow rates at sites 34 and 35 on the Mississippi River to lesser magnitude than that observed during the previous during the 2016 surveys were less than 1 percent different than surveys during the July/August 2011 flood, and of an equal to the 2010 flow rates, and about 6 percent lower than the 2009 greater magnitude during the previous surveys during gener- flow rate at site 33 (table 7), implying similar, nonflood condi- ally lower flow in 2010. Generally, this assumption proved to tions during both surveys at each site. Water-surface eleva- be true, with only minor exceptions. tions were about 1 to 2 ft lower in 2016 than in the previous Flow rates at the Missouri River sites (sites 23 to 27) nonflood survey (table 7), and the average difference (sta- during the 2016 surveys ranged from about 20 to 50 percent tistical mean) between the bathymetric surfaces varied from greater than the 2010 flow rate, and water-surface elevations 1.4 ft lower to 0.8 ft higher in 2016 than the previous survey were 1.5 to 3.5 ft higher in 2016 than in 2010 (table 7). The (table 7). When the average channel-bed elevation is exam- average difference (statistical mean) between the bathymetric ined with time (fig. 60), there is more variation in the aver- surfaces varied from 1.8 ft lower to 0.9 ft higher in 2016 than age channel-bed elevations at a given site on the Mississippi 2010 (table 7). Alternatively, flow rate at the Missouri River River than on the Missouri River, and the average channel-bed sites during the 2016 surveys ranged from about 49 to 58 per- elevation of the 2016 surveys fell above the previous survey, cent of the 2011 flow rate, and water-surface elevations were as might be expected given the discharge ratios of the 2016 about 7 to 9 ft lower in 2016 than in 2011 (table 7), and the compared to the previous survey. average difference (statistical mean) between the bathymet- In the multiple surveys at structures A4936/A1850 (site ric surfaces varied from 0.3 ft lower to 2.2 ft higher in 2016 35), the flow rate of the May 2009 survey was high enough to than 2011 (table 7). When the average channel-bed elevation be considered a “flood” survey, with the 2016 flow rate being is examined with time (fig. 60), there generally appears to be about 68 percent of the May 2009 flow rate and similar in only small variation in the average channel-bed elevations at magnitude to the 2011 flood as measured at the streamgage at a given site on the Missouri River, and generally, the average St. Charles, Mo. The water-surface elevation was over 13 ft channel-bed elevation of the 2016 surveys fell between the lower in 2016 than in May 2009 (table 7), but the average two previous surveys, as might be expected given the dis- channel-bed elevation was only 0.2 ft lower in 2016 than in charge ratios of the 2016 compared to the previous surveys. May 2009 (table 7). In fact, in all the surveys at this site, the However, average channel-bed elevation at structures A3292/ average difference between the bathymetric surfaces only L0561 (site 25) was higher in 2016 than in either 2010 or ranged from 0.2 ft lower to 0.8 ft higher, regardless of the flow 2011, and the average channel-bed elevation at dual bridge conditions (table 7). structure A5585 (site 24) is closer to the 2011 bed elevation An examination of the frequency distributions of bed ele- than is seen at other sites on the Missouri (table 7; fig. 60). vations in the 2016 surveys compared to the previous surveys Structures A3292/L0561 in particular had a positive aver- reveals additional differences that may be the result of flow age difference between the bathymetric surfaces from 2016 conditions during the 2016 surveys (fig. 61). The frequency to 2011 and from 2016 to 2010 (table 7), the only site to be distributions generally were narrower in the 2016 survey than so. This configuration of average channel-bed elevations in the 2011 survey at each site, with a higher percentage of and average differences shows that greater discharge alone survey-grid cells in a particular elevation range (fig. 61A). The does not necessarily result in more scour at a site (as would narrower distribution curves result in generally steeper cumu- be evidenced by lower average channel-bed elevations with lative percentage curves in 2016 than in 2011, but not as steep increased discharge). as in 2010 (fig. 61B). Cumulative percentage curves that are The lack of variability in the average channel-bed eleva- steep indicate a channel bed with a narrower range of eleva- tions at dual bridge structure A4557 (site 26) and structure tions (more level throughout the reach), whereas those that are A3047 (site 27) further downstream may indicate these sites less steep indicate a wider variation of elevations. Cumulative are at or near a local feature that controls sediment deposition percentage curves with “steps” indicate a channel with distinct 82 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
460 E PLANATION 450
Average water-surface 440 elevation 2016 survey data 430 2009 or 2011 (flood) survey data Confluence of Missouri and 2009 or 2010 (nonflood)
420 Mississippi Rivers at river mile
195.2 on the Mississippi River survey data A6500, site 33 A1500, site 34 A4936/A1850, site 35 410 Average channel-bed elevation 2016 survey data 400 2009 or 2011 (flood) survey data
Vertical Datum of 1988 390 2009 or 2010 (nonflood) survey data 380 Elevation, in feet above the North American A5585, site 24 A4557, site 26 A3047, site 27 370 A3292/L0561, site 25 A7577/A4017, site 23
360 Missouri Mississippi River River
350 50 40 30 20 10 0 185 175 165 River mile
Figure 60. Average channel-bed and water-surface elevations near bridges on the Missouri and Mississippi Rivers near St. Louis, Missouri, from surveys in 2009, 2010, 2011, and 2016. groups of elevations, such as thalweg on one side and a shal- downstream sites. The similarity of channel-bed elevations low area on the opposite side of the channel (such as structure cause the cumulative percentage curves to be very similar to A3047, figs. 34 and 35); however, some of the steps in the one another, as well as to plot close together (fig. 61B). Part cumulative percentage curves are the result of collecting more of the difference in bed slope may be the result of the Chain information higher on the banks by tilting the MBES head in of Rocks, the remains of a natural geologic formation and an the later surveys than was done in 2010. old river control structure (Missouri Department of Con- The frequency distributions seem to confirm the hypo- servation, 2017), which creates a grade control of the river thetical scenario of a sediment control feature near dual downstream from structure A0890 on Interstate 270 and the bridge structure A4557 postulated in the average channel-bed Old Chain of Rocks Bridge (fig. 1), resulting in a difference elevation curve discussion above. The frequency distribution in the channel-bed elevation upstream and downstream of curves for structures A7577/A4017 and structures A3292/ this feature. Unfortunately, data have not been collected at L0561 have local maxima with a higher percentage of survey- either structure A6500 or A1500 during a flood comparable grid cells than other sites on the Missouri (fig. 61A). As would to the May 2009 event surveyed at structures A4936/A1850 be expected, these maxima are at a lower elevation than sites or the 2011 event on the Missouri River. upstream from them and generally at a higher elevation than most of sites downstream; however, the distribution curve for Size and Shape of Scour Holes dual bridge structure A4557 consistently has a local maximum that is at a higher elevation than the next upstream site, and the Scour holes were observed at most piers in the main cumulative percentage curve is close to and occasionally to the channel area, except those on banks or surrounded by riprap right of (implying a higher elevation than) the next upstream or debris rafts. As discussed in summaries of previous bathy- site in the surveys (fig. 61B). metric surveys in Missouri (Huizinga, 2010, 2011, 2012, 2014, The similarity of the frequency distributions and cumu- 2015, 2016), the size and shape of these holes often was differ- lative percentage curves of the Mississippi River sites (sites ent from pier to pier because pier scour is a function of several 33–35) is remarkable (fig. 61B). Whereas the Missouri River factors, including the depth and velocity of approach flow, the sites exhibit a relatively constant bed slope throughout the width and nose shape of the pier, and the angle of approach reach, the Mississippi River sites are substantially lower, flow (Richardson and Davis, 2001). The effect of several of and all have similar average channel-bed elevations (fig. 60; these factors on scour holes observed during the 2016 surveys table 5), despite the distance between the upstream and are discussed below. Results of Bathymetric and Velocimetric Surveys 83
A. Frequency distribution B. Cumulative percentage 4.0 100 2009 or 2010 nonflood survey 2009 or 2010 90 3.5 nonflood survey 80 3.0 70 2.5 60
2.0 50
40 1.5 30 1.0 20 0.5 10
0 0 2.5 100 2009 or 2011 flood survey 2009 or 2011 flood survey 90
2.0 80
70
1.5 60
50
1.0 40
30
0.5 20 Percentage of total survey-grid cells 10
0 0 3.0 100 2016 survey 2016 survey 90
2.5 Cumulative percentage of survey-grid cells lower than indicated elevation 80
70 2.0 60
1.5 50
40 1.0 30
20 0.5 10
0 0 320 330 340 350 360 370 380 390 400 410 420 430 440 450 320 330 340 350 360 370 380 390 400 410 420 430 440 450 Elevation, in feet above the North American Vertical Datum of 1988
E PLANATION E PLANATION Structures A7577/A4017, site 23 Structure A3047, site 27 Structures A7577/A4017, site 23 Structure A3047, site 27 Dual structure A5585, site 24 Structure A6500, site 33 Dual structure A5585, site 24 Structure A6500, site 33 Structures A3292/L0561, site 25 Structure A1500, site 34 Structures A3292/L0561, site 25 Structure A1500, site 34 Dual structure A4557, site 26 Structures A4936/A1850, Dual structure A4557, site 26 Structures A4936/A1850, site 35 site 35
Figure 61. Comparison of frequency distribution and cumulative percentage of bed elevations for bathymetric survey-grid cells from various surveys on the Missouri and Mississippi Rivers near St. Louis, Missouri. A, frequency distribution. B, cumulative percentage. 84 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
A longitudinal profile was drawn upstream from the nose of the survey at these highway bridge sites. The approximate of each pier with a well-defined scour hole, and the approxi- frontal slope of the well-defined scour holes at the railroad mate frontal slope (computed as horizontal distance over bridge piers ranged from 1.67 to 3.39 (fig. 65); however, the vertical distance, or run over rise, for relatability to highway hole with the largest slope value—or the shallowest frontal embankment slopes) was determined for each hole (tables 6, slope—(3.39 at the right main channel pier of the Wabash 8). The frontal slope was not determined for piers with poorly railroad bridge; figs. 27, 65B) was observed in an area with a defined scour holes. Profiles for selected piers are shown in nearly planar bed with low velocities (fig. 29), which indicate figures 62 through 64. minimal sediment transport in that area. Piers in similar planar The approximate frontal slope of the well-defined scour bed areas near dual bridge structure A5585 (pier 7 of both holes for sites on the Missouri River ranged from 1.06 to eastbound and westbound bridges; fig. 13) also demonstrated 3.03 (figs. 62, 63; table 6). Several scour holes at the Mis- very shallow frontal slopes (figs. 62H, 62K; table 6). souri River sites had frontal slopes of values greater than 3.03, Several of the surveyed bridges had piers that were but generally scour holes near these piers were substantially skewed to approach flow, resulting in asymmetric scour holes affected by an upstream pier (table 6). The approximate frontal at those bridges: bents 7 and 8 of structure A7577 and pier 5 slope of the well-defined scour holes for sites on the Missis- of structure A4017 on U.S. Highway 40 (fig. 6); pier 15 of sippi River ranged from 1.28 to 2.27 (fig. 64; table 8). The structure A3292 and pier 16 of structure L0561 on Interstate mean value of the frontal slopes at the Missouri River sites not 70 (fig. 20); pier 3C of dual bridge structure A4557 on State affected by upstream piers was 2.09 (table 6), and the mean Highway 370 (fig. 27); pier 11 of structure A6500 on Inter- value at the Mississippi River sites was 1.79 (table 8). Rich- state 70 (fig. 40); and pier 12 of structures A4936 and A1850 ardson and Davis (2001) noted that the side slope of a scour on Interstate 255 (fig. 51). Generally, the scour hole was hole in cohesionless sand in air could range from 1.0 to 1.8 longer on the side of the pier with impinging flow, with some depending on the composition of the bed material and its dry amount of deposition on the leeward side, as typically has angle of repose, and suggest using a value of 2.0 for design been observed at piers skewed to approach flow; however, at purposes to account for the wet angle of repose. The slope val- most of the skewed piers in the current (2016) study, the scour ues determined in the current (2016) study generally are simi- hole was deeper on the leeward side of the pier (see bent 7, lar to the values noted in Richardson and Davis (2001) and to structure A7577 [fig. 6]; pier 15, structure A3292 [fig. 20]; values determined for scour holes in similar studies (Huizinga, downstream pier 3C, structure A4557 [fig. 27]; and pier 11, 2010, 2011, 2015, 2016), and are similar to previous surveys structure A6500 [fig. 40]). At most of these piers, the angled at these sites (figs. 62–64). approach flow was the result of a deflection or contraction of A longitudinal profile also was drawn upstream from flow caused by a spur dike near the pier (figs. 6, 20, 27), which the nose of the railroad bridge piers near dual bridge struc- may affect flow differently than for a simple skew. At structure ture A4557 and near structure A3047, and the approximate A6500, the very wide face of the pier footing and seal course frontal slope was determined for each hole (fig. 65). Although (over 55 ft) would behave as a complex foundation, for which analysis of scour near the railroad bridges was not within the scour is computed differently (Richardson and Davis, 2001). scope of the study, these railroad bridges were in close prox- At all of the structures, the skew to approach flow is apparent imity to the highway bridges, and fell within the boundaries in the velocity vectors (figs. 12, 22, 29, 45, 55). Results of Bathymetric and Velocimetric Surveys 85
c c' d d' e e' 435 440 450 A. Structure A7577, Bent 7 B. Structure A7577, Bent 8 C. Structure A7577, Bent 9 430 435 445 Front of Face of Face of 425 Drilled Shaft 430 Base Shaft 440 Base Shaft
420 425 435
415 420 430
410 415 425 Footing Footing 405 410 420
f f' g g' 440 450 D. Structure A4017, Pier 5 E. Structure A4017, Pier 6 E PLANATION 435 445 Channel bed from 2016 bathymetric surveys, in feet above the North 430 Face of 440 Face of American Vertical Datum of 1988 Pedestal Pedestal Channel bed from 2011 bathymetric surveys, in feet above the North 425 435 American Vertical Datum of 1988 Channel bed from 2010 bathymetric 420 430 surveys, in feet above the North American Vertical Datum of 1988 Approximate frontal slope line 415 425 Pier substructural elements
410 420
c c' d d' e e' 430 430 435 F. Structure A5585, Pier 5 East G. Structure A5585, Pier 6 East H. Structure A5585, Pier 7 East 425 425 430 Face of Face of Pedestal 420 Face of 420 Pedestal 425 Pedestal 415 415 420
410 410 415
405 405 410 Channel-bed elevation, in feet above the North American Vertical Datum of 1988 Footing Footing 400 400 405
f f' g g' h h' 430 430 440 I. Structure A5585, Pier 5 West J. Structure A5585, Pier 6 West K. Structure A5585, Pier 7 West 425 425 435 Face of Face of Face of 420 Pedestal 420 Pedestal 430 Pedestal
415 415 425
410 410 420
405 405 415
Footing Footing 400 400 410 50 40 30 20 10 0 50 40 30 20 10 0 50 40 30 20 10 0 Distance upstream from pier face, in feet
Figure 62. Longitudinal profiles upstream from selected piers at structures A7577 and A4017 on U.S. Highway 40, and at dual bridge structure A5585 on State Highway 364, crossing the Missouri River near St. Louis, Missouri 86 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
c c' d d' 425 420 A. Structure A3292, Pier 15 B. Structure A3292, Pier 16 420 Trapped Debris 415 Face of Pedestal 415 410 Face of 410 Pedestal 405
405 400 E PLANATION 400 395 Channel bed from 2016 bathymetric surveys, in feet above the North Footing Footing American Vertical Datum of 1988 395 390 Channel bed from 2011 bathymetric 80 60 40 20 0 50 40 30 20 10 0 surveys, in feet above the North e e' f f' American Vertical Datum of 1988 430 415 Channel bed from 2010 bathymetric C. Structure L0561, Pier 16 D. Structure L0561, Pier 17 surveys, in feet above the North 425 410 American Vertical Datum of 1988 Face of Face of Approximate frontal slope line Pedestal Pier substructural elements 420 Pedestal 405
415 400
410 395
405 Caisson 390 Caisson 400 385 40 30 20 10 0 50 40 30 20 10 0 c c' d d' e e' 420 420 420 E. Structure A4557, Pier 2C East F. Structure A4557, Pier 3C East G. Structure A4557, Pier 2C West 415 Face of 415 Face of 415 Face of Pedestal Pedestal Pedestal 410 410 410
405 405 405
400 400 400 Footing Footing Footing
395 395 395 Channel-bed elevation, in feet above the North American Vertical Datum of 1988 Seal course Seal course Seal course
390 390 390 40 30 20 10 0 40 30 20 10 0 40 30 20 10 0 b b' c c' 405 415 H. Structure A3047, Pier 11 I. Structure A3047, Pier 12 400 Face of 410 Face of Pedestal Pedestal 395 405 Submerged object on nose of pier 390 400
385 395
380 390
375 385 40 30 20 10 0 40 30 20 10 0 Distance upstream from pier face, in feet
Figure 63. Longitudinal profiles upstream from selected piers at structures A3292 and L0561 on Interstate 70, at dual bridge structure A4557 on State Highway 370, and at structure A3047 on U.S. Highway 67, crossing the Missouri River near St. Louis, Missouri. Results of Bathymetric and Velocimetric Surveys 87
b b' c c' 385 375 A. Structure A6500, Pier 12 B. Structure A6500, Pier 11 380 370 Seal course Face of Footing 2009 preconstruction 375 365 survey line Seal course
370 2016 top of 360 riprap blanket 2016 top of riprap 365 355 2009 preconstruction E PLANATION 360 survey line 350 Channel bed from 2016 bathymetric surveys, in feet above the North American Vertical Datum of 1988 355 345 100 80 60 40 20 0 100 80 60 40 20 0 Channel bed from 2009 (flood) bathymetric surveys, in feet above the A A' A A' 365 375 North American Vertical Datum of 1988 C. Structure A1500, Pier 4 D. Structure A1500, Pier 3 Channel bed from 2009/2010 (nonflood) Face of bathymetric surveys, in feet above the 360 Pedestal 370 Face of North American Vertical Datum of 1988 Pedestal Approximate frontal slope line Footing Pier substructural elements 355 365 Seal course Footing 350 360
345 355
340 350 Seal course
335 345 50 40 30 20 10 0 50 40 30 20 10 0 A A' C C' 395 380 375 E. Structure A1850, Pier 7 F. Structure A4936, Pier 8 G. Structure A4936, Pier 9 390 375 Face of 370 Face of Face of Column Pedestal Column Pedestal 385 370 365 Footing
380 365 Footing 360 Pedestal Seal 375 360 355 course
370 355 Seal course 350 Channel-bed elevation, in feet above the North American Vertical Datum of 1988 Footing Piles Seal course Piles 365 350 345
E E' B B' D D' 375 390 380 H. Structure AA4936/1850, Pier 12 I. Structure A1850, Pier 8 J. Structure A1850, Pier 9 370 385 375 Face of Column Face of Face of Column 365 Pedestal 380 370 Pedestal Pedestal 360 375 365 Footing
355 370 360
Footing 350 365 355 Seal course Footing Seal course Seal course Piles 345 360 350 50 40 30 20 10 0 50 40 30 20 10 0 50 40 30 20 10 0 Distance upstream from pier face, in feet
Figure 64. Longitudinal profiles upstream from selected piers at structure A6500 on Interstate 70, at structure A1500 on Interstate 55, and at structures A4936 and A1850 on Interstate 255, crossing the Mississippi River near St. Louis, Missouri. 88 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
f f' g g' 415 425 A. Wabash Railroad Bridge, B. Wabash Railroad Bridge, 410 Left Pier 420 Right Pier
405 415
400 410 Slope = 2.70 Slope = 1.87 395 405 Slope = 3.39 E PLANATION 390 400 Channel bed from 2016 bathymetric surveys, in feet above the North American Vertical Datum of 1988 385 395 Channel bed from 2011 bathymetric 60 40 20 0 40 30 20 10 0 surveys, in feet above the North d d' e e' American Vertical Datum of 1988 400 410 Channel bed from 2010 bathymetric C. Bellefontaine Railroad Bridge, D. Bellefontaine Railroad Bridge, surveys, in feet above the North 395 Left Pier 405 Right Pier American Vertical Datum of 1988 Approximate frontal slope line Pier substructural elements 390 400
385 395 Slope = 1.67
380 390 Slope = 2.41
375 385 Channel-bed elevation, in feet above the North American Vertical Datum of 1988
370 380 40 30 20 10 0 40 30 20 10 0 Distance upstream from pier face, in feet
Figure 65. Longitudinal profiles upstream from railroad bridge piers near dual bridge structure A4557 on State Highway 370, and near structure A3047 on U.S. Highway 67, crossing the Missouri River near St. Louis, Missouri.
Summary and Conclusions data at all the sites have a total propagated uncertainty of less than 0.50 feet, and over three-quarters (78 percent or more) of Bathymetric and velocimetric data were collected on the the channel-bed elevations at the sites have a total propagated Missouri and Mississippi River near 13 highway bridges at uncertainty of 0.25 feet or less. 8 crossings in the greater St. Louis, Mo., area by the U.S. Geo- At all the surveyed bridges, a variety of fluvial features logical Survey in cooperation with the Missouri Department were detected in the channel ranging from small ripples to of Transportation. A multibeam echosounder mapping system large dunes that indicate moderate transport of bedload. Two was used to obtain channel-bed elevations for areas rang- sites had areas of a planar or nearly-planar bed, indicating ing from 1,640 to 1,970 feet longitudinally and generally minimal sediment transport in these areas. Rock outcrops also extending across the active channel from bank to bank in the were detected along one bank at several sites where the allu- Missouri and Mississippi Rivers during low to moderate flood vial material of the channel bed had been washed away. flow conditions. These surveys document the channel-bed con- Bathymetric data were collected around every pier that ditions and velocity distribution at the time of the surveys and was in water, except those at the edge of water, and scour provide characteristics of scour holes that may be useful in the holes were observed at most surveyed piers. The observed development of predictive guidelines or equations for scour scour holes at the surveyed bridges were examined with holes. These data also may be used by the Missouri Depart- respect to shape and depth. ment of Transportation as a moderate flow comparison to help At structure A6500 at Interstate 70 crossing the Missis- assess the bridges for stability and integrity issues with respect sippi River, the previous survey was part of a habitat assess- to bridge scour during floods. ment before construction of the bridge, which gives unique The estimated total propagated uncertainty for the insight into the effects of the construction of structure A6500 bathymetric surface of each survey area was computed as an on the channel in this reach. Although the discharge and estimate of the accuracy to be expected for each point with all water-surface elevation for the survey on May 25, 2016, were relevant error sources taken into account. An analysis of the similar to during the preconstruction survey on July 7, 2009, surveys indicated that more than 97 percent of the bathymetric the difference between the bathymetric surfaces from each References Cited 89 survey indicated moderate scour overall in the reach from various surveys at this site only ranged from 0.2 feet lower to 2009 to 2016, with an average difference of –1.36 ft between 0.8 feet higher, regardless of the flow conditions. the bathymetric surfaces. Substantial scour of nearly 30 feet The frontal slope values determined for scour holes was observed at and downstream from pier 11. Both piers are observed in the current (2016) study generally are similar to skewed to approach flow, and the scour hole near pier 11 has recommended values in the literature and to values determined the typical characteristics of a hole at a skewed pier, being for scour holes in previous bathymetric surveys. Several of longer on the side with impinging flow, and with a line of the structures had piers that were skewed to primary approach deposition on the leeward side. However, the wide, square flow, and generally, the scour hole was longer on the side of nose of the pier, a mild constriction downstream from the pier, the pier with impinging flow with some amount of deposi- and additional scour from adjacent mooring dolphins down- tion on the leeward side, as typically has been observed at stream likely have exacerbated the scour on the leeward side piers skewed to approach flow; however, at a majority of the of the pier by increasing local turbulence and pulling sediment skewed piers in the current (2016) study, the scour hole was into suspension. A riprap blanket surrounds pier 12, and seems deeper on the leeward side of the pier. At most of these piers, to limit scour near that pier. the angled approach flow was the result of a deflection or Flow rates at the Missouri River sites (sites 23 to 27) contraction of flow caused by a spur dike near the pier, which during the 2016 surveys ranged from about 20 to 50 percent may affect flow differently than for a simple skew. At structure greater than the 2010 flow rate, and water-surface elevations A6500, the very wide face of the pier footing and seal course were 1.5 to 3.5 feet higher in 2016 than in 2010. Alternatively, would behave as a complex foundation, for which scour is flow rate at the Missouri River sites during the 2016 surveys computed differently. ranged from about 49 to 58 percent of the 2011 flow rate, and water-surface elevations were about 7 to 9 feet lower in 2016 than in 2011. The average difference between the bathymetric References Cited surfaces varied from 1.8 feet lower to 0.9 feet higher in 2016 than 2010, and varied from 0.3 feet lower to 2.2 feet higher in ™ ™ 2016 than 2011. The average channel-bed elevation exhibits Applanix Corporation, 2009, POS-Pac MMS GNSS-inertial only small variation with time at the Missouri River sites, tools user guide, rev. 4: Richmond Hill, Ontario, Canada, and generally, the average channel-bed elevation of the 2016 PUBS–MAN–001768, 523 p. surveys fell between the two previous surveys, as might be Calder, B.R., and Mayer, L.A., 2003, Automatic processing of expected given the discharge ratios of the 2016 compared to high-rate, high-density multibeam echosounder data: Geo- the previous surveys. However, the lack of variability in the chemistry, Geophysics, Geosystems (G3), v. 4, no. 6, 22 p. average channel-bed elevations at dual bridge structure A4557 [Also available at https://doi.org/10.1029/2002GC000486.] (site 26) and structure A3047 (site 27) farther downstream may indicate these sites are at or near a local feature that con- Czuba, J.A., Best, J.L, Oberg, K.A., Parsons, D.R., Jackson, trols sediment deposition and scour. P.R., Garcia, M.H., and Ashmore, Peter, 2011, Bed mor- Flow rates at sites 34 and 35 on the Mississippi River phology, flow structure, and sediment transport at the outlet during the 2016 surveys were less than 1 percent different than of Lake Huron and in the Upper Saint Clair River: Journal the 2010 flow rates, and about 6 percent lower than the 2009 of Great Lakes Research, v. 37, no. 3, p. 480–493. [Also flow rate at site 33; water-surface elevations were about 1 to available at https://doi.org/10.1016/j.jglr.2011.05.011.] 2 feet lower in 2016 than in the previous survey. The aver- age difference between the bathymetric surfaces varied from Densmore, B.K., Strauch, K.R., and Dietsch, B.J., 2013, 1.4 feet lower to 0.8 feet higher in 2016 than the previous sur- Hydrographic surveys of the Missouri and Yellowstone Riv- vey. The average channel-bed elevation exhibits more varia- ers at selected bridges and through Bismarck, North Dakota, tion with time than the Missouri River sites, and generally, the during the 2011 flood: U.S. Geological Survey Scientific average channel-bed elevation of the 2016 surveys fell above Investigations Report 2013–5087, 59 p. [Also available at the previous survey, as might be expected given the discharge https://pubs.usgs.gov/sir/2013/5087/.] ratios of the 2016 compared to the previous survey. Dietsch, B.J., Densmore, B.K., and Strauch, K.R., 2014, The flow rate of the May 2009 survey at structures Hydrographic surveys at selected highway bridges crossing A4936 and A1850 (site 35) was high enough to be considered the Missouri River using a multibeam echosounder, 2011: a “flood” survey, with the 2016 flow rate being about 68 per- U.S. Geological Survey Scientific Investigations Report cent of the May 2009 flow rate and similar in magnitude to 2014–5062, 53 p. [Also available at https://doi.org/10.3133/ the 2011 flood as measured at the streamgage at St. Charles, sir20145062.] Mo. The water-surface elevation was over 13 feet lower in 2016 than in May 2009, but the average channel-bed elevation Esri, 2013, ArcGIS: Environmental Systems Research Institute was only 0.2 feet lower in 2016 than in May 2009. The aver- (Esri), accessed July 2013 at http://www.esri.com/software/ age difference between the bathymetric surfaces from all the arcgis/. 90 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Gilbert, G.K., and Murphy, E.C., 1914, The transport of débris Huizinga, R.J., Elliott, C.M., and Jacobson, R.B., 2010, Bathy- by running water: U.S. Geological Survey Professional metric and velocimetric survey and assessment of habitat Paper 86, 263 p. [Also available at https://pubs.er.usgs.gov/ for pallid sturgeon on the Mississippi River in the vicinity publication/pp86.] of the proposed Interstate 70 Bridge at St. Louis, Missouri: U.S. Geological Survey Scientific Investigations Report Huizinga, R.J., 2010, Bathymetric surveys at highway bridges 2010–5017, 28 p. [Also available at https://pubs.usgs.gov/ crossing the Missouri River in Kansas City, Missouri, using sir/2010/5017/.] a multibeam echo sounder, 2010: U.S. Geological Survey Scientific Investigations Report 2010–5207, 61 p. [Also Huizinga, R.J., and Rydlund, P.H., Jr., 2004, Potential- available at https://pubs.usgs.gov/sir/2010/5207/.] scour assessments and estimates of scour depth using different techniques at selected bridge sites in Missouri: Huizinga, R.J., 2011, Bathymetric surveys at highway bridges U.S. Geological Survey Scientific Investigations Report crossing the Missouri and Mississippi Rivers near St. Louis, 2004–5213, 42 p. [Also available at https://pubs.usgs.gov/ Missouri, 2010: U.S. Geological Survey Scientific Investi- sir/2004/5213/.] gations Report 2011–5170, 75 p. [Also available at https:// pubs.usgs.gov/sir/2011/5170/.] HYPACK, Inc., 2015, HYPACK® hydrographic survey software user manual: Middletown, Conn., HYPACK, Inc., Huizinga, R.J., 2012, Bathymetric and velocimetric surveys 2,041 p. at highway bridges crossing the Missouri River in and into Missouri during summer flooding, July–August 2011: International Hydrographic Organization, 2008, IHO standards U.S. Geological Survey Scientific Investigations Report for hydrographic surveys (5th ed.): Monaco, International 2012–5204, 166 p. [Also available at https://pubs.usgs.gov/ Hydrographic Bureau, Special publication No. 44, 27 p. sir/2012/5204/.] Lagasse, P.F., Shall, J.D., Johnson, F., Richardson, E.V., Huizinga, R.J., 2013, Results of repeat bathymetric and veloci- Richardson, J.R., and Chang, F., 1991, Stream stability at metric surveys at the Amelia Earhart Bridge on U.S. High- highway structures: U.S. Federal Highway Administration way 59 over the Missouri River at Atchison, Kansas, Publication FHWA–IP–90–014, Hydraulic Engineering 2009–2013: U.S. Geological Survey Scientific Investiga- Circular no. 20, 195 p. tions Report 2013–5177, 50 p. [Also available at https:// pubs.usgs.gov/sir/2013/5177.] Missouri Department of Conservation, 2017, Chain of Rocks hazard: Missouri River Water Trail: Missouri Department of Huizinga, R.J., 2014, Bathymetric and velocimetric surveys Conservation, accessed April 2017 at https://missouririver- at highway bridges crossing the Missouri River between watertrail.org/safety/chain-rocks-hazard. Kansas City and St. Louis, Missouri, April–May, 2013: U.S. Geological Survey Scientific Investigations Report Mueller, D.S., Wagner, C.R., Rehmel, M.S., Oberg, K.A., and 2014–5116, 79 p. [Also available at https://doi.org/10.3133/ Rainville, Francois, 2013, Measuring discharge with acous- sir20145116.] tic Doppler current profilers from a moving boat (ver. 2.0, December 2013): U.S. Geological Survey Techniques and Huizinga, R.J., 2015, Bathymetric and velocimetric surveys at Methods, book 3, chap. A22, 95 p. [Also available at https:// highway bridges crossing the Missouri and Mississippi Riv- doi.org/10.3133/tm3A22.] ers on the periphery of Missouri, June 2014: U.S. Geologi- cal Survey Scientific Investigations Report 2015–5048, 81 National Marine Electronics Association, 2002, NMEA p. [Also available at https://doi.org/10.3133/sir20155048.] 0183—Standard for interfacing marine electronic devices (ver. 3.01): National Marine Electronics Association, 88 p. Huizinga, R.J., 2016, Bathymetric and velocimetric surveys at highway bridges crossing the Missouri River near Kan- Parsons, D.R., Jackson, P.R., Czuba, J.A., Engel, F.L., Rhoads, sas City, Missouri, June 2–4, 2015: U.S. Geological Survey B.L., Oberg, K.A., Best, J.L., Mueller, D.S., Johnson, Scientific Investigations Report 2016–5061, 93 p. [Also K.K., and Riley, J.D., 2013, Velocity Mapping Toolbox available at https://doi.org/10.3133/sir20165061.] (VMT)—A processing and visualization suite for moving- vessel ADCP measurements: Earth Surface Processes and Huizinga, R.J., 2017, Bathymetry and velocity data from sur- Landforms, v. 38, no. 11, p. 1244–1260. [Also available at veys at highway bridges crossing the Missouri and Missis- https://doi.org/10.1002/esp.3367.] sippi Rivers near St. Louis, Missouri, October 2008 through May 2016: U.S. Geological Survey data release, https://doi. Richardson, E.V., and Davis, S.R., 2001, Evaluating scour at org/10.5066/F71C1VCC. bridges (4th ed.): U.S. Federal Highway Administration Publication FHWA NHI 01–001, Hydraulic Engineering Circular no. 18, 378 p. References Cited 91
Rydlund, P.H., Jr., 2009, Real-time river channel-bed moni- toring at the Chariton and Mississippi Rivers in Missouri, 2007–09: U.S. Geological Survey Scientific Investigations Report 2009–5254, 27 p. [Also available at https://pubs. usgs.gov/sir/2009/5254/.] Simons, D.B., Richardson, E.V., and Nordin, C.F., Jr., 1965, Bedload equation for ripples and dunes: U.S. Geological Survey Professional Paper 462–H, 9 p. [Also available at https://pubs.er.usgs.gov/publication/pp462H.] U.S. Army Corps of Engineers, 2003a, Upper Mississippi River System flow frequency study, appendix D: Rock Island, Ill., U.S. Army Corps of Engineers, accessed April 2017 at http://www.mvr.usace.army.mil/Portals/48/ docs/FRM/UpperMissFlowFreq/App.%20D%20St.%20 Louis%20Dist.%20Hydrology_Hydraulics.pdf. U.S. Army Corps of Engineers, 2003b, Upper Mississippi River System flow frequency study, appendix E: Rock Island, Ill., U.S. Army Corps of Engineers, accessed April 2017 at http://www.mvr.usace.army.mil/Portals/48/docs/ FRM/UpperMissFlowFreq/App.%20E%20Kansas%20 City%20Dist.%20Hydrology_Hydraulics.pdf. U.S. Army Corps of Engineers, 2013, Engineering and design—Hydrographic surveying: Washington D.C., U.S. Army Corps of Engineers, manual no. EM 1110–2– 1003, 560 p. U.S. Geological Survey, 2003, User’s manual for the National Water Information System of the U.S. Geological Survey— Automated Data Processing System (ADAPS): U.S. Geo- logical Survey Open-File Report 2003–123, 413 p., accessed September 2010 at https://pubs.usgs.gov/of/2003/ ofr03123/. U.S. Geological Survey, 2017, National Water Information System: U.S. Geological Survey database, accessed April 2017 at https://doi.org/10.5066/F7P55KJN.
Appendix 1. Shaded Triangulated Irregular Network Images of the Channel and Side of Pier for Each Surveyed Pier 94 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Drilled shafts, Bent 6, A7577 Spur dike A E PLANATION Pier 4, A4017 Elevation, in feet above the North Construction American Vertical Datum of 1988 dike Missing data 444 Flow 440 436 Drilled shafts, Bent 7, A7577 432 428 B 424 420 416 412 Flow 408 404 Drilled shafts, Bent 7, A7577 400
C
Flow
Remant of Bent 8, A7577 D Pier 5, J1000 Pier 5, A4017
Flow
Remant of Pier 5, J1000 Pier 5, A4017 E Bent 8, A7577
Flow
Bent 9, A7577 Pier 6, A4017 F Figure 1–1. Shaded triangulated irregular Top of footing network visualization of the channel bed and Missing data Flow bents and piers of structures A7577 and A4017 on U.S. Highway 40 crossing the Missouri River near St. Louis, Missouri. A, right (south) Pier 6, A4017 side of bent 6 and pier 4. B, left (north) side of Bent 9, A7577 bent 7. C, right (south) side of bent 7. D, left G (north) side of bent 8 and pier 5. E, right (south) side of bent 8 and pier 5. F, left (north) side of Flow bent 9 and pier 6. G, right (south) side of bent 9 and pier 6. Appendix 1. Shaded Triangulated Irregular Network Images of the Channel and Side of Pier for Each Surveyed Pier 95
Pier 5 Eastbound Pier 5 Westbound E PLANATION A Elevation, in feet above the North American Vertical Datum of 1988 432 430 Flow 428 426 424 422 Pier 5 Eastbound Pier 5 Westbound 420 B 418 416 414 412 Flow 410 408 406 Pier 6 Eastbound 404 Pier 6 Westbound 402 400 C
Flow
Pier 6 Eastbound Pier 6 Westbound D
Flow
Pier 7 Eastbound Pier 7 Westbound E
Flow
Pier 7 Eastbound F Pier 7 Westbound
Flow
Missing data
Figure 1–2. Shaded triangulated irregular network visualization of the channel bed and piers of dual bridge structure A5585 on State Highway 364 crossing the Missouri River near St. Louis, Missouri. A, left (north) side of pier 5. B, right (south) side of pier 5. C, left (north) side of pier 6. D, right (south) side of pier 6. E, left (north) side of pier 7. F, right (south) side of pier 7. 96 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
A Debris raft at Pier 15, A3292 nose of pier Pier 16, L0561
Missing data Flow
B Debris raft at nose of pier Pier 15, A3292 Pier 16, L0561
Flow Missing data
Pier 16, A3292 Pier 17, L0561 C
Flow
Pier 16, A3292 Pier 17, L0561
D
Top edge of footing Flow
E PLANATION Elevation, in feet above the North American Vertical Datum of 1988
388 391 394 397 400 403 406 409 412 415 418 421 424 427 430
Figure 1–3. Shaded triangulated irregular network visualization of the channel bed and piers of structures A3292 and L0561 on Interstate 70 crossing the Missouri River near St. Louis, Missouri. A, left (northwest) side of piers 15 and 16. B, right (southeast) side of piers 15 and 16. C, left (northwest) side of piers 16 and 17. D, right (southeast) side of piers 16 and 17. Appendix 1. Shaded Triangulated Irregular Network Images of the Channel and Side of Pier for Each Surveyed Pier 97
E PLANATION Pier 2C Westbound Pier 2C Eastbound Elevation, in feet above the North A American Vertical Datum of 1988 427 Top of footing 424 Submerged Top of footing log 421 Flow 418 415 412 Pier 2C Westbound Pier 2C Eastbound 409 406 B 403 Submerged 400 log 397 Top of footing 394 Flow 391 388 Pier 3C Eastbound Pier 3C Westbound C Spur dike
Submerged log Top of footing Top of footing Flow
Pier 3C Eastbound Pier 3C Westbound D
Submerged log Spur dike
Flow
Pier 4C Westbound Pier 4C Eastbound E
Spur dike
Flow
Figure 1–4. Shaded triangulated irregular network visualization of the channel bed and piers of dual bridge structure A4557 on State Highway 370 crossing the Missouri River near St. Louis, Missouri. A, left (northwest) side of pier 2C. B, right (southeast) side of pier 2C. C, left (northwest) side of pier 3C. D, right (southeast) side of pier 3C. E, left (northwest) side of pier 4C. 98 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Pier 10 Longitudinal dike Longitudinal dike E PLANATION Elevation, in feet above the North A American Vertical Datum of 1988 410 407 Flow 404 401 398 395 Pier 11 392 389 B 386 383 380 Flow 377 374
Pier 11
C
Flow
Pier 12 D Submerged object Flow
Pier 12 E
Submerged object Missing data Flow
Figure 1–5. Shaded triangulated irregular network visualization of the channel bed and piers of structure A3047 on U.S. Highway 67 crossing the Missouri River near St. Louis, Missouri. A, right (south) side of pier 10. B, left (north) side of pier 11. C, right (south) side of pier 11. D, left (north) side of pier 12. E, right (south) side of pier 12. Appendix 1. Shaded Triangulated Irregular Network Images of the Channel and Side of Pier for Each Surveyed Pier 99
Footing of Pier 12 A
Riprap blanket Riprap blanket
Flow
B Stone revetment on bank Stone revetment on bank Footing of Pier 12
Riprap blanket Seal course Riprap blanket Flow
Footing of Pier 11 C Pier 17, L0561
Submerged Seal course objects Missing data Flow on side of (and under) Seal course Riprap piled around pier
Footing of Pier 11
D
Submerged objects Approximate bottom of Seal course “Hazy” data on side of (and under) Seal course Riprap piled around pier Flow
E PLANATION Elevation, in feet above the North American Vertical Datum of 1988
388 391 394 397 400 403 406 409 412 415 418 421 424 427 430
Figure 1–6. Shaded triangulated irregular network visualization of the channel bed and piers of structure A6500 on Interstate 70 crossing the Mississippi River in St. Louis, Missouri. A, left (east) side of pier 12. B, right (west) side of pier 12. C, left (east) side of pier 11. D, right (west) side of pier 11. 100 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
A Pier 5 E PLANATION Flow Elevation, in feet above the North American Vertical Datum of 1988 394 Pier 5 390 B 386 382 Flow Sonic shadow from 378 Mooring dolphin Mooring dolphin 374 370 Pier 4 C 366 362 358 354 Flow 350 346 342 338 Pier 4 D
Flow
E Pier 3
Flow
Pier 3 F
Flow
G Pier 2 Figure 1–7. Shaded triangulated irregular network visualization of the channel bed piers Flow of structure A1500 on Interstate 55 over the Mississippi River in St. Louis, Missouri. A, left (east) side of pier 5. B, right (west) side of pier H 5. C, left (east) side of pier 4. D, right (west) Pier 2 side of pier 4. E, left (east) side of pier 3. Flow F, right (west) side of pier 3. G, left (east) side of pier 2. H, right (west) side of pier 2. Appendix 1. Shaded Triangulated Irregular Network Images of the Channel and Side of Pier for Each Surveyed Pier 101
Pier 7, A1850 Pier 7, A4936 E PLANATION A Flow Elevation, in feet above the North American Vertical Datum of 1988 387 384 381 378 B 375 Pier 7, A4936 Pier 7, A1850 372 369 Flow 366 363 Missing data 360 357 Pier 8, A1850 Pier 8, A4936 354 351 C 348 Flow
Pier 8, A4936 Pier 8, A1850 D
Flow
Pier 9, A1850 Pier 9, A4936
E
Flow
Pier 9, A4936 Pier 9, A1850
F Flow
Submerged objects
Figure 1–8. Shaded triangulated irregular network visualization of the channel bed and piers of structures A4936 and A1850 on Interstate 255 crossing the Mississippi River near St. Louis, Missouri. A, left (east) side of pier 7. B, right (west) side of pier 7. C, left (east) side of pier 8. D, right (west) side of pier 8. E, left (east) side of pier 9. F, right (west) side of pier 9. 102 Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO
Pier 10, A1850 A Pier 10, A4936 E PLANATION Elevation, in feet above the North American Vertical Datum of 1988 Flow 387 384 381 Piles of riprap 378 375 Pier 10, Pier 10, A4936 A1850 372 B 369 Flow 366 363 360 357 Piles of riprap 354 Pier 11, 351 Pier 11, A4936 A1850 348 C
Flow
Piles of riprap
Pier 11, Pier 11, A4936 A1850
D Flow
Piles of riprap
Pier 12, A4936 & A1850 E
Flow
Pier 12, A4936 & A1850 F
Figure 1–9. Shaded triangulated irregular Flow network visualization of the channel bed and piers of structures A4936 and A1850 on Interstate 255 crossing the Mississippi River Pier 13, A4936 & A1850 near St. Louis, Missouri. A, left (east) side of G pier 10. B, right (west) side of pier 10. C, left (east) side of pier 11. D, right (west) side of pier 11. E, left (east) side of pier 12. F, right Flow (west) side of pier 12. G, left (east) side of pier 13. Publishing support provided by: Rolla Publishing Service Center
For additional information concerning this publication, contact: Director, USGS Missouri Water Science Center 1400 Independence Road Rolla, MO 65401 (573) 308–3667
Or visit the Missouri Water Science Center Web site at: https://mo.water.usgs.gov Huizinga—
Flow Bathymetric and Velocimetric Surveys at Highway Bridges Crossing the Missouri and Mississippi Rivers near St. Louis, MO —SIR 2017–5076
ISSN 2328-0328 (online) http://dx.doi.org/10.3133/sir20175076