Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, Using a Multibeam Echo Sounder, 2010

Prepared in cooperation with the Missouri Department of Transportation

Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

Scientific Investigations Report 2010–5207

U.S. Department of the Interior U.S. Geological Survey Technical Report Documentation Page

1. Report No.: 2. Government Accession No.: 3. Recipient's Catalog No.: OR11-008 4. Title and Subtitle: 5. Report Date: Bathymetric Surveys at Highway Bridges Crossing the November 2010 Missouri River in Kansas City, Missouri, using a 6. Performing Organization Code: Multibeam Echo Sounder, 2010 7. Author(s): 8. Performing Organization Report U.S. Department of the Interior No.: Ken Salazar, Secretary U.S. Geological Survey Marcia K. McNutt, Director 9. Performing Organization Name and Address: 10. Work Unit No.: U.S. Geological Survey, Reston, Virginia 11. Contract or Grant No.: TRyy 10 19 12. Sponsoring Agency Name and Address: 13. Type of Report and Period Missouri Department of Transportation Covered: Organizational Results PO BOX 270 14. Sponsoring Agency Code: Jefferson City, MO 65102 15. Supplementary Notes The investigation was conducted in cooperation with the U. S. Department of Transportation, Federal Highway Administration. 16. Abstract: Bathymetric surveys were conducted by the U.S. Geological Survey, in cooperation with the Missouri Department of Transportation, on the Missouri River in the vicinity of nine bridges at seven highway crossings in Kansas City, Missouri, in March 2010. A multibeam echo sounder mapping system was used to obtain channel-bed elevations for river reaches that ranged from 1,640 to 1,800 feet long and extending from bank to bank in the main channel of the Missouri River. These bathymetric scans will be used by the Missouri Department of Transportation to assess the condition of the bridges for stability and integrity with respect to bridge scour.

17. Key Words: 18. Distribution Statement Bathymetric, Bridges, Scour, Missouri River, No restrictions. This document is available Kansas City to the public through National Technical Information Center, Springfield, Virginia 22161 19. Security Classification 20. Security Classification 21. No. of Pages: 22. Price: (of this report): (of this page): 74 Unclassified Unclassified Form DOT F 1700.7 (06/98) Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

By Richard J. Huizinga

Prepared in cooperation with the Missouri Department of Transportation

Scientific Investigations Report 2010–5207

U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2010

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Suggested citation: Huizinga, R.J., 2010, Bathymetric surveys at highway bridges crossing the Missouri River in Kansas City, Missouri, using a multibeam echo sounder, 2010: U.S. Geological Survey Scientific Investigations Report 2010–5207, 61 p. iii

Contents

Abstract ...... 1 Introduction...... 1 Purpose and Scope ...... 2 Description of Study Area ...... 2 Equipment and Methods Used in Bathymetric Surveys ...... 3 Description of Equipment ...... 3 Multibeam Echo Sounder ...... 4 Navigation and Motion-Sensing System ...... 4 Data Collection and Processing Computer ...... 4 Description of Survey Methods ...... 6 Survey Quality-Assurance/Quality-Control Measures ...... 7 Beam Angle Check ...... 7 Patch Tests ...... 8 Results of Bathymetric Surveys ...... 10 Structure A1800 on Interstate 635 ...... 11 Structures K0456 and A0450 on U.S. Highway 69 ...... 18 Structure A4649 on U.S. Highway 169 ...... 24 Structure A4060 on State Highway 9 ...... 29 Structure A5817 on State Highway 269 ...... 37 Structure A0767 on Interstate 435 ...... 43 Structures A4757 and L0568 on State Highway 291 ...... 49 General Findings and Implications ...... 55 Shape of Scour Holes ...... 55 Long-Term Channel-Bed Changes ...... 55 Effects of Moderate Flooding During Surveys ...... 57 Error Estimation ...... 58 Summary...... 60 References Cited...... 60 iv

Figures

1. Map showing location of bridges crossing the Missouri River in the Kansas City, Missouri, area ...... 3 2. Photographs showing the multibeam echo sounder as viewed A, from the bottom, B, from the top, and C, mounted on the port side of the U.S. Geological Survey boat ...... 5 3. Diagram showing approximate beam geometry of the multibeam echo sounder A, across ship track and B, along ship track ...... 6 4. Diagram showing approximate beam geometry of the multibeam echo sounder with a tilted head to obtain soundings A, along a river bank or B, on the side of a vertical structure ...... 6 5. Diagram showing method of survey line spacing used to ensure complete coverage of the channel bed and minimize sonic “shadows” ...... 7 6. Diagram show effects of timing and angular offsets for A, latency, B, roll, C, pitch, and D, yaw on data from a multibeam echo sounder ...... 9 7. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structure A1800 on Interstate 635 in Kansas City, Missouri ...... 12 8. Bathymetric survey of the Missouri River channel in the vicinity of structure A1800 on Interstate 635 in Kansas City, Missouri ...... 13 9. Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A1800 on Interstate 635 in Kansas City, Missouri ...... 14 10. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A1800 on Interstate 635 over the Missouri River in Kansas City, Missouri ...... 15 11. Point cloud visualization of the channel bed and left (north) side of the main channel pier of structure A1800 on Interstate 635 over the Missouri River in Kansas City, Missouri ...... 17 12. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri ...... 19 13. Bathymetric survey of the Missouri River channel in the vicinity of structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri ...... 20 14. Bathymetric survey of the Missouri River channel in the vicinity of the main channel piers of structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri ...... 21 15. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure K0456 on U.S. Highway 69 over the Missouri River in Kansas City, Missouri ...... 22 16. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A0450 on U.S. Highway 69 over the Missouri River in Kansas City, Missouri ...... 23 17. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structure A4649 on U.S. Highway 169 in Kansas City, Missouri...... 25 18. Bathymetric survey of the Missouri River channel in the vicinity of structure A4649 on U.S. Highway 169 in Kansas City, Missouri ...... 26 19. Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A4649 on U.S. Highway 169 in Kansas City, Missouri ...... 27 v

20. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A4649 on U.S. Highway 169 over the Missouri River in Kansas City, Missouri ...... 28 21. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structure A4060 on State Highway 9 in Kansas City, Missouri ...... 30 22. Bathymetric survey of the Missouri River channel in the vicinity of structure A4060 on State Highway 9 in Kansas City, Missouri ...... 31 23. Bathymetric survey of the Missouri River channel in the vicinity of the right main channel pier of structure A4060 on State Highway 9 in Kansas City, Missouri ...... 32 24. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A4060 on State Highway 9 over the Missouri River in Kansas City, Missouri ...... 33 25. Point cloud visualization of the channel bed and right (south) side of the right main channel pier (pier 6) of structure A4060 on State Highway 9 over the Missouri River in Kansas City, Missouri ...... 34 26. Bathymetric survey of the Missouri River channel in the vicinity of the left main channel pier of structure A4060 on State Highway 9 in Kansas City, Missouri ...... 35 27. Point cloud visualization of the channel bed and right (south) side of the left main channel pier (pier 5) of structure A4060 on State Highway 9 over the Missouri River in Kansas City, Missouri ...... 36 28. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structure A5817 on State Highway 269 in Kansas City, Missouri ...... 38 29. Bathymetric survey of the Missouri River channel in the vicinity of structure A5817 on State Highway 269 in Kansas City, Missouri ...... 39 30. Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A5817 on State Highway 269 in Kansas City, Missouri ...... 40 31. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A5817 on State Highway 269 over the Missouri River in Kansas City, Missouri ...... 41 32. Point cloud visualization of the channel bed and left (north) side of the main channel pier of structure A5817 on State Highway 269 over the Missouri River in Kansas City, Missouri ...... 42 33. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structure A0767 on Interstate 435 in Kansas City, Missouri ...... 44 34. Bathymetric survey of the Missouri River channel in the vicinity of structure A0767 on Interstate 435 in Kansas City, Missouri ...... 45 35. Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A0767 on Interstate 435 in Kansas City, Missouri ...... 46 36. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A0767 on Interstate 435 over the Missouri River in Kansas City, Missour ...... 47 37. Point cloud visualization of the channel bed and left (north) side of the main channel pier of structure A0767 on Interstate 435 over the Missouri River in Kansas City, Missouri ...... 48 38. Aerial photograph showing location of the bathymetric survey area on the Missouri River near structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri ...... 50 vi

39. Bathymetric survey of the Missouri River channel in the vicinity of structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri ...... 51 40. Bathymetric survey of the Missouri River channel in the vicinity of the main channel piers of structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri ...... 52 41. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure A4757 on State Highway 291 over the Missouri River in Kansas City, Missouri ...... 53 42. Diagram showing key features, substructural and superstructural details, and surveyed channel bed of structure L0568 on State Highway 291 over the Missouri River in Kansas City, Missouri ...... 54 43. Graphs showing longitudinal profiles upstream from piers at the structures surveyed on the Missouri River at Kansas City, Missouri...... 56 44. Scatter plot showing water-surface elevation for a given discharge range with time from measurements made at the streamflow-gaging station on the Missouri River at Kansas City, Missouri ...... 57 45. Scatter plot showing average channel-bed elevation with time from measurements made at the streamflow-gaging station on the Missouri River at Kansas City, Missouri ...... 58 46. Aerial photograph showing total propagated error of bathymetric data from the Missouri River channel in the vicinity of structure A1800 on Interstate 635 in Kansas City, Missouri ...... 59

Tables

1. Bridges crossing the Missouri River in the Kansas City, Missouri, area, in downstream order ...... 2 2. Results of a beam angle check from two check lines over a reference surface at Blue Springs Lake, Missouri, on March 18, 2010 ...... 8 3. Results of patch tests performed each day of surveying on the Missouri River in Kansas City, Missouri, and at Blue Springs Lake, Missouri ...... 9 4. Bridge and survey information and minimum elevations in the channel and scour holes from surveys on the Missouri River in Kansas City, Missouri, from March 15–18, 2010 ...... 11 5. Results at upstream pier faces from surveys on the Missouri River in Kansas City, Missouri, from March 15–18, 2010 ...... 16 vii

Conversion Factors

Inch/Pound to SI

Multiply By To obtain Length inch (in.) 2.54 centimeter (cm) foot (ft) 0.3048 meter (m) mile (mi) 1.609 kilometer (km) Flow rate cubic foot per second (ft3/s) 0.02832 cubic meter per second (m3/s)

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 (NAVD 88). The difference between NAVD 88 and the National Geodetic Vertical Datum of 1929 (NGVD 29) ranges from 0.26 to 0.28 foot throughout the study area, with an average value of 0.27 foot. Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83). In this report, the words “left” and “right” generally refer to directions that would be reported by an observer facing downstream. viii Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

By Richard J. Huizinga

Abstract was lower than the channel bed obtained during Level II scour assessments in 2002. At piers with well-defined scour holes, the frontal slopes Bathymetric surveys were conducted by the U.S. Geo- of the holes were somewhat less than recommended values logical Survey, in cooperation with the Missouri Department in the literature, and the shape of the holes appeared to be of Transportation, on the Missouri River in the vicinity of nine affected by the movement of dune features into and around bridges at seven highway crossings in Kansas City, Missouri, the holes. The channel bed at all of the surveyed sites was in March 2010. A multibeam echo sounder mapping system lower than the channel bed at the time of construction, and an was used to obtain channel-bed elevations for river reaches analysis of measurement data from the U.S. Geological Survey that ranged from 1,640 to 1,800 feet long and extending from continuous streamflow-gaging station on the Missouri River at bank to bank in the main channel of the Missouri River. These Kansas City, Missouri (station number 06893000), confirmed bathymetric scans will be used by the Missouri Department of a lowering trend of the channel-bed elevations with time at the Transportation to assess the condition of the bridges for stabil- gaging station. ity and integrity with respect to bridge scour. The size of the scour holes observed at the surveyed sites Bathymetric data were collected around every pier likely was affected by the moderate flood conditions on the that was in water, except those at the edge of the water or in Missouri River at the time of the surveys. The scour holes extremely shallow water, and one pier that was surrounded by likely would be substantially smaller during conditions of low a large debris raft. A scour hole was present at every pier for flow. which bathymetric data could be obtained. The scour hole at a given pier varied in depth relative to the upstream channel bed, depending on the presence and proximity of other piers or structures upstream from the pier in question. The surveyed Introduction channel bed at the bottom of the scour hole was between 5 and 50 feet above bedrock. Scour is the removal of channel bed and bank material At bridges with drilled shaft foundations, generally there by flowing water and is the leading cause of bridge failures was exposure of the upstream end of the seal course and the in the United States (Richardson and Davis, 2001). Scour at seal course often was undermined to some extent. At one site, a bridge site is the result of long-term geomorphological pro- the minimum elevation of the scour hole at the main channel cesses and the local effects caused by elements of the struc- pier was about 10 feet below the bottom of the seal course, ture in or adjacent to the waterway (Richardson and Davis, and the sides of the drilled shafts were evident in a point cloud 2001; Huizinga and Rydlund, 2004). Because the effects can visualization of the data at that pier. However, drilled shafts be severe and dangerous, bridges and other structures over generally penetrated 20 feet into bedrock. Undermining of the waterways are routinely assessed and inspected for the effects seal course was evident as a sonic “shadow” in the point cloud of scour. visualization of several of the piers. The Missouri Department of Transportation (MoDOT) Large dune features were present in the channel at nearly is responsible for most of transportation infrastructure that all of the surveyed sites, as were numerous smaller dunes and benefits the welfare of Missouri citizens. A part of this respon- many ripples. Several of the sites are on or near bends in the sibility is fulfilled through periodic inspections of highway river, resulting in a deep channel thalweg on the outside of the structures, including bridges that span waterways throughout bend at these sites. At structure A5817 on State Highway 269, the State. At most of these structures, all or most of the struc- bedrock exposure was evident in the channel thalweg. The ture can be fully inspected from land or from personnel lift surveyed channel bed at a given site from this study generally trucks deployed from the roadway of the structure. However, 2 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 for structures over major waterways, such as the Missouri and on Interstate 29/35 currently (2010) is in the process of being Mississippi Rivers, inspection of the part of the bridge that is replaced with the Christopher S. Bond Bridge (kcICON Proj- underwater requires a different approach. ect, 2010) and, therefore, does not currently (2010) require an Beginning in 1991, the U.S. Geological Survey (USGS), underwater inspection. in cooperation with MoDOT, has assessed scour at waterway crossings throughout the state (Huizinga and Rydlund, 2004). In 2007, the USGS began determining channel bathymetry and Purpose and Scope monitoring bridges for scour using single beam echo sounders The purpose of this report is to document bathymetric and a multibeam mapping system (Rydlund, 2009; Huizinga surveys of the Missouri River channel in the vicinity of nine and others, 2010). In particular, the multibeam mapping sys- highway bridges at seven crossings of the river in Kansas tem has proven to be a useful tool not only in the determina- City, Missouri, obtained by using a multibeam echo sounder tion of channel bathymetry, but also in providing medium- to in 2010. Equipment and methods used and results obtained are high-resolution imagery of bridge structural elements below described. The results obtained from the bathymetric surveys the water line. Therefore, the USGS, in cooperation with of the channel can be used to assess the bridges for stability MoDOT, began conducting a series of bathymetric surveys at and integrity issues with respect to bridge scour, and provide various highway bridges across major waterways in Missouri characteristics of scour holes that may be useful in the devel- in 2010. opment of predictive guidelines or equations for scour holes. Ten highway bridges and three railroad bridges span the Missouri River in the Kansas City, Missouri, area (table 1; fig. 1); the 10 highway bridges are under the responsibility of Description of Study Area MoDOT. The U.S. Highway 69 crossing of the river consists of two bridges (structures K0456 and A0450), and the State The overall study area for this report is the Missouri Highway 291 crossing of the river consists of two bridges River in Kansas City, Missouri (fig. 1). The Missouri River (structures A4757 and L0568). Therefore, 10 highway bridges flows through the Kansas City area from west to east, mean- at 8 unique crossings of the Missouri River in the Kansas City dering across the flood plain. The river is highly channelized area routinely are inspected by MoDOT (Jennifer Harper, Mis- in the Kansas City area, with rock revetment and spur dikes souri Department of Transportation, written commun., 2010). along the banks to maintain the channel alignment and levees Of the 10 highway bridges crossing the Missouri River and floodwalls on the upper banks to limit flooding in the in the Kansas City area, 9 were surveyed, as indicated in industrial, commercial, and agricultural areas in the flood table 1. The Paseo Bridge (structure L0734; table 1; fig. 1) plains.

Table 1. Bridges crossing the Missouri River in the Kansas City, Missouri, area, in downstream order.

[MoDOT, Missouri Department of Transportation; IS, Interstate highway; --, not known/applicable; US, U.S. highway; S, southbound; N, northbound; BNSF, Burlington Northern Santa Fe; MO, State highway]

MoDOT Surveyed as structure Local name County Route part of this Remarks Figures number study A1800 Riverside Platte IS 635 Yes -- 7, 8, 9, 10, 11 K0456 Fairfax Platte US 69 S Yes Dual bridge crossing with A0450 12, 13, 14, 15 A0450 Fairfax Toll Platte US 69 N Yes Dual bridge crossing with K0456 12, 13, 14, 16 A4649 Broadway Avenue Clay US 169 Yes -- 17, 18, 19, 20 -- Second Hannibal Clay BNSF No Railroad bridge -- -- ASB Clay BNSF No Railroad bridge -- A4060 Heart of America Clay MO 9 Yes -- 21, 22, 23, 24, 25, 26, 27 L0734 Paseo Clay IS 29/35 No Currently (2010) being replaced -- A5817 Chouteau Clay MO 269 Yes -- 28, 29, 30, 31, 32 A0767 Randolph Clay IS 435 Yes -- 33, 34, 35, 36, 37 -- Harry S Truman Clay BNSF No Railroad bridge -- A4757 Courtney Jackson MO 291 S Yes Dual bridge crossing with L0568 38, 39, 40, 41 L0568 Courtney Jackson MO 291 N Yes Dual bridge crossing with A4757 38, 39, 40, 42 Equipment and Methods Used in Bathymetric Surveys 3

94°38' 94°36' 94°34' 94°32' 94°30' 94°28' 94°26' 94°24'

1 35 9 29 435 169 L0568

39°10' 283 A4757 RIVER 635

MISSOURI 291 A0450 210 K0456 210 RIVER A1800 A0767 Harry S 9 Truman 69 Railroad 169 Bridge A5817 39°08' 269 Second FLOW Hannibal MISSOURI Railroad Bridge A4649 L0734

A4060 MISSOURI

KANSAS 24 ASB 39°06' Railroad 24 Bridge Kansas City, Missouri 670 70 435 69 169

78 RIVER 70 KAN SAS 35

Base from National Agricultural Imagery Program, 2006 0 1 2 3 MILES Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) 0 1 2 3 KILOMETERS

LOCATION MAP EXPLANATION Map area Missouri River Principal railroad route

U.S. Geological Survey KANSAS streamflow-gaging station on the Missouri River at MISSOURI Kansas City, station 06893000

FigureFigure 1. Location1. Location of bridges of bridges crossing crossing the Missouri the Missouri River in River the Kansasin the Kansas City, Missouri, City, Missouri, area. area.

Equipment and Methods Used in Description of Equipment Bathymetric Surveys A multibeam mapping system is an integration of several individual components: the multibeam echo sounder (MBES), The bathymetry of the Missouri River at each of the a navigation and motion-sensing system, and a data collection bridges was determined using a high-resolution multibeam and processing computer. The navigation system locates the mapping system. The various components of the multibeam MBES in three-dimensional space, and the motion-sensing mapping system used for this study are the same as used in a system measures the heave, pitch, roll, and heading of the previous study on the Mississippi River near St. Louis, Mis- vessel (and, thereby, the MBES) to accurately position the souri (Huizinga and others, 2010), and the survey methods data received by the MBES. The data from the MBES and used to obtain the data were similar, as were the measures navigation and motion-sensing components are processed and used to ensure data quality. Nevertheless, the equipment and integrated into a cohesive dataset for cleanup and visualization methods are discussed below for completeness. by the data collection and processing computer. 4 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

Multibeam Echo Sounder the survey vessel was near or under the bridge. These GPS outages had the potential to degrade the positional accuracy of The MBES that was used is the RESON SeaBat™ 7125, the vessel until such time as an RTK-fixed navigation solution which consists of projector and receiver arrays of piezoceram- was re-acquired. However, the navigation information from the ics (fig. 2A) operating at a frequency of 400 kilohertz (kHz) survey was post-processed using the POS-Pac™ Mobile Map- attached to a fixed, tiltable head mounted on a retracting pole ping Suite (MMS™) software (Applanix Corporation, 2009), on the port side of the USGS survey boat (fig. 2). A sound- which provided tools to identify and compensate for sensor and velocity probe (SVP-71; fig. 2B) also is attached to the head environmental errors and computed an optimally blended navi- to measure the speed of sound in water near the projector and gation solution from the GPS and IMU raw data. This blended receiver arrays, which is critical to the accurate determina- navigation solution is called a “standard best-estimate of tion of depth (Hughes-Clarke and others, 1996; RESON, Inc., travel” (SBET) and represents the best-estimate of the motion 2008; fig. 2B). Settings for and data from the MBES are pro- of the vessel while minimizing the root mean square error of cessed through the RESON 7K Controller software (RESON, the estimated navigation solution. The SBET file generated by Inc., 2008) on the 7-P Sonar Processing Unit computer (here- post-processing the navigation data was applied to the entire inafter referred to as “the 7-P computer”). survey at a given bridge to minimize the effects of the GPS The projector and receiver arrays can operate in depths outages while surveying under the bridges. from 3 to 656 feet (ft). The projector array emits one sound wave that the receiver array forms into 512 equidistant beams with spacing of less than 0.25 degree (°) distributed across Data Collection and Processing Computer the ship track and 1° wide along the track (fig. 3). This beam A laptop computer onboard the survey boat (hereinaf- geometry can generate up to a 128° swath that can cover up ter referred to as “the field computer”) ran the HYPACK®/ to 4.1 times the water depth across track (fig. 3) with up to HYSWEEP® data acquisition software (HYPACK, Inc., 2009) 512 depth readings with each sounding. The head tilt bracket which was used to prepare for the bathymetric surveys, collect (fig. 2B) permits the head to be tilted to obtain soundings at and process the survey data, and create various output prod- shallower depths along river banks or on vertical walls or pier ucts from the surveys. A map or other background image of surfaces (fig. 4). the survey area was imported and used to plan and execute the survey. The bathymetric sounding data and the naviga- Navigation and Motion-Sensing System tion and position solution collected and processed by the 7-P computer were transmitted by high-speed local area network The navigation and motion-sensing system that was used (LAN) ethernet connection to the field computer. During the is the Applanix Position Orientation Solution for Marine Ves- survey, the navigation and position solution from the POS was sels (POS MV™) WaveMaster system (hereinafter referred used to keep the survey boat on a proper heading by means of to as “the POS”), which utilizes dual Trimble Zephyr Global a helms display for the boat captain. Continual screen refresh- Positioning System (GPS) antennae for navigation combined ing provided a low-resolution real-time map of the survey as with an inertial motion unit (IMU) for vessel motion sens- it progressed, which permitted the immediate re-acquisition of ing. The POS is used to measure the vessel motion, so that data in areas that were missed during the survey. data received from the MBES can be correctly positioned in Upon completion of the surveys, the acquired depth three-dimensional space as the vessel rotates and moves on data were processed using the HYPACK®/HYSWEEP® the water surface. Information from the dual GPS antennae on software to remove data spikes and other spurious points in the boat is combined with a real-time kinetic (RTK) correc- the multibeam swath trace, using a variety of tools and filters tion from a fixed GPS base station on the riverbank to provide to identify and selectively remove potential erroneous data a navigation and tide solution with an accuracy of 0.79 inch points. After cleanup, the depth data were georeferenced using (in.) in the absence of structures that might block signal from the navigation and position solution data from the SBET file the GPS constellation of satellites (Applanix Corporation, from POS-Pac™ MMS™, and were visualized in HYPACK®/ 2006). The IMU records vessel motion (pitch, roll, yaw, and HYSWEEP® as a triangulated irregular network (TIN) surface heave) with an accuracy of 0.03° for pitch, roll, and yaw, and or a point cloud. 5 percent of the heave amplitude, or 1.96 in., whichever is The georeferenced data also were output to a comma- greater (Applanix Corporation, 2006). The IMU also provides delimited file with no data reduction or filtered and reduced an inertial position solution that is reliable through RTK out- based on a desired data resolution. These comma-delimited ages for periods of less than about 1 minute. Settings for and data were compiled into a geographic information system data from the POS are processed through the MV-POSView (GIS) database for each site using the ArcGIS package Controller software (Applanix Corporation, 2006) on the 7-P (Environmental Systems Research Institute, 2010). ArcGIS is computer during the survey. a collection of software packages that allow data editing and Because the bathymetric surveys were conducted at high- attribution, data display and review, data processing, genera- way bridge crossings, the bridge structure would block a part or tion of interpolated of data, and map-product creation (Wilson the entire signal from the GPS constellation of satellites when and Richards, 2006). Equipment and Methods Used in Bathymetric Surveys 5

SVP-71 sound velocity probe

Piezoceramic projector array

Head tilt bracket

Fixed, tiltable head

Piezoceramic receiver array

A B

C Figure 2. The multibeam echo sounder as viewed (A) from the bottom, (B) from the top, and (C) mounted on the port Figure side of 2. the The U.S. multibeam Geological echo Survey sounder boat as. viewed A, from the bottom, B, from the top, and C, mounted on the port side of the U.S. Geological Survey boat. 6 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

A B

0 0

10 10

20 20

Feet below sounder 30 Feet below sounder 30 0-10-20-30-40-50-60 10 20 30 40 50 60 0 01 -10 Feet from sounder Feet from sounder

Figure 3.3. Approximate Approximate beambeam geometry geometry of of the the multibeam multibeam echo echo sounder sounder A, across(A) across ship shiptrack track and B and, along (B) shipalong track. ship track.

A B

0 0

10 10

20 20

Feet below sounder 30 Feet below sounder 30 0-10-20-30-40 10 20 30 Feet from sounder 40 -50 0-10-20-30-40 10 20 30 Feet from sounder

Figure 4.4. Approximate Approximate beambeam geometry geometry of of the the multibeam multibeam echo echo sounder sounder with with a tilted a tilted head head to obtain to obtain soundings soundings A, along a river (A) bankalong or a B river, on thebank side or of(B a) verticalon the side structure. of a vertical structure.

Description of Survey Methods (fig. 3), the boat was positioned so that there was about 50 percent overlap with the adjacent surveyed data, which provided The GPS base station used for the RTK navigation and about 150 percent coverage of the channel bed and ample tide solution during the survey was set up on the river bank, coverage on both sides of any feature that might create a sonic near the bridge to be surveyed. In general, the surveyed “shadow” (fig. 5). Substantial overlap was achieved for all of area extended bank to bank in the main channel of the river the surveyed swaths, except in shallow areas near the chan- and was from 1,640 to 1,800 ft long, positioned so that the nel banks on the inside of channel bends or near debris rafts. surveyed highway bridge was approximately one-third to Because of the overlap, the outermost beams generally were one-half of the total length from the upstream boundary. The removed from a given swath without compromising cover- boundaries of the surveyed area were assumed to be beyond age. The outer beams were most susceptible to small errors in the hydraulic effect of the bridge structure. boat position and attitude or the effects of refraction (Hughes- To ensure complete coverage of the channel bed and Clarke and others, 1996). minimize sonic “shadows,” each survey was designed so that Channel-bed coverage along a given survey line is depen- there was overlap of the survey swaths. Sonic “shadows” dent on the speed of the vessel relative to the channel bottom occur when a tall feature present in the water column prevents (hereinafter referred to as “absolute boat speed”) and the data- soundings behind the object (fig. 5). Survey lines were spaced acquisition rate (hereinafter referred to as “ping rate”) of the at 49.2-ft intervals across the survey area orthogonal to the MBES. In the riverine environment, the survey boat requires flow direction at each bridge. Data were not acquired along enough forward velocity to overcome the current and travel every survey line at a given bridge site, but the survey lines upstream, whereas on downstream passes, the survey boat were used to orient the boat during data acquisition. Knowing has to have enough velocity to enable steering. Therefore, the that the beam geometry of the MBES provides a swath width survey boat always has greater absolute boat speed traveling that is approximately 4.1 times the water depth across track downstream than traveling upstream. To provide equivalent Equipment and Methods Used in Bathymetric Surveys 7

Location of survey lines, spaced about 49.2 feet apart

First pass Second pass Third pass

Feature on the channel bed

Channel bed scanned Channel bed scanned on on first and second Sonic “shadow” second and third passes, passes for 150 percent created by feature Sonic “shadow” resulting in less than coverage in third pass created by feature 150 percent coverage but in second pass removal of sonic “shadows”

FigureFigure 5. 5. Method ofof surveysurvey line line spacing spacing used used to to ensure ensure complete complete coverage coverage of the of thechannel channel bed bedand minimizeand minimize sonic “shadows.” sonic “shadows.” coverage in the upstream and downstream directions, the ping were encountered near outfalls from tributaries. When one of rate of the MBES was altered relative to the absolute boat these pockets was encountered, it changed the speed of sound speed to generate one ping approximately every 0.5 ft. as measured by the SVP-71 on the MBES transducer head The Missouri River was in moderate flood conditions (fig. 2B), which invariably altered the measured depth to the from rainfall and snowmelt when the bathymetric surveys channel bed for the duration of several pings of the MBES. were performed March 15 through 18, 2010. The discharge However, the location of these warmer pockets generally was ranged from 120,000 to 129,000 cubic feet per second (ft3/s), away from the substructural elements of the surveyed bridge. as measured at the USGS streamflow-gaging station (hereinaf- The altered depths near these outfalls were not edited if the ter referred to as “streamgage”) on the Missouri River at Kan- effect was small compared to nearby unaffected depths, or the sas City, Missouri (station 06893000), on the Second Hannibal swaths containing the altered depths were removed. railroad bridge (U.S. Geological Survey, 2010)—a discharge exceeded daily less than 5 percent of the time (U.S. Geologi- cal Survey, 2003), but less than the 50 percent annual exceed- Survey Quality-Assurance/Quality-Control ance probability (2-year return interval) flood discharge of Measures 142,000 ft3/s (U.S. Army Corps of Engineers, 2004a). Because of the higher stage, surveys from bank to bank generally were For the MBES mapping system, the principal quality- possible in the main channel with sufficient depth to clear rock assurance assessments were performed in real time during the spur dikes and other flow structures. However, strong flow survey. The MBES operator was continuously assessing the velocity in the channel thalweg made headway against the quality of the collected data during the survey, making visual current difficult; therefore, the channel thalweg generally was observations of across-track swaths (such as convex, concave, surveyed downstream, and upstream passes were made away or skewed bed returns in flat, smooth bottoms), noting data from the thalweg. The presence of flood debris rafts made quality flags and alarms from the MBES and the POS, and not- surveying difficult or impossible at some piers. ing comparisons between adjacent overlapping swaths. How- Because knowledge of the speed of sound in water is crit- ever, in addition to the real-time quality-assurance assessments ical to the accurate measurement of distances using a MBES during the survey, several tests were performed to ensure the (Hughes-Clarke and others, 1996), routine sound-velocity quality of the data acquired by the MBES mapping system. profile casts are taken during surveys in lakes or oceans For this survey, a beam angle check and a suite of patch tests to determine the presence of thermoclines and accurately were performed to ensure quality data were acquired from the measure the speed of sound throughout the water column. MBES mapping system. However, in the riverine environment, flow mixing is assumed to maintain a constant speed of sound throughout the water Beam Angle Check column. The riverine speed of sound, as measured by the SVP-71, was monitored during the survey at a given bridge, A beam angle check is used to determine the accuracy of and generally did not deviate by more than 0.05 percent during the depth readings obtained by the outer beams of the MBES the survey. Nevertheless, occasional pockets of warmer water (U.S. Army Corps of Engineers, 2004b). The HYPACK®/ 8 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

HYSWEEP® software has a program that will perform a of the transducer head (fig. 6). A set of patch tests was per- statistical assessment of the quality of the outer beams com- formed each day of surveying, and a summary of the results is pared to a reference surface. On March 18, 2010, a reference shown in table 3. surface was created for a portion of Blue Springs Lake near A latency test measures the timing offset between the Blue Springs, Missouri [on the southeastern side of Kansas MBES and the GPS components of the POS, Δt (fig. 6A). In City about 11 miles south-southwest of structures A4754 and a latency test, a line that is perpendicular to a slope or dis- L0568 on State Highway 291 (fig. 1)], and check lines were tinct feature on the channel bed is surveyed twice in the same run across the reference surface. direction, but at slow and fast vessel speeds. Errors will appear The results of the beam angle check (table 2) were within as a horizontal offset in the slope or feature between the two the recommended standards utilized by the U.S. Army Corps surveyed lines. For this set of surveys, there was no measured of Engineers for hydrographic surveys for angles less than timing offset (Δt = 0; table 3), which is consistent with latency 60° from nadir (U.S. Army Corps of Engineers, 2004b). To test results for this boat and configuration used in other sur- mitigate errors associated with depths for angles greater than veys (Huizinga and others, 2010; Richard Huizinga, U.S. Geo- 60° from nadir, these points were removed from the swath logical Survey, unpub. data, 2010). A roll test measures the angular offset of the transducer for survey lines in the deep part of the channel. These points head along the longitudinal axis of the boat, α (fig. B6 ), which were not removed in shallow areas because the relative effect leads to horizontal and vertical position errors of a measured of depth errors is lessened, and the channel bed coverage was channel-bed point. In a roll test, a line over a relatively flat more likely to be compromised by removal of the points. channel bed is surveyed twice in opposite directions at the same speed. An angular offset for roll error will cause the Patch Tests flat bed to appear sloped in opposing directions across the reciprocal lines. For the March 2010 surveys, the measured Patch tests are a series of dynamic calibration tests that angular offset for roll ranged from 0.21° to 0.29° (table 3) are used to check for subtle variations in the orientation and from the first day of surveying to the last, which indicates timing of the MBES with respect to the POS and real world that the transducer head was bending during the week of coordinates. The patch tests are used to determine timing off- surveying. Examination of the transducer head after the sets caused by latency between the MBES and the POS, and surveys confirmed that the head tilt bracket (fig.B 2 ) had been angular offsets to roll, pitch, and yaw caused by the alignment slightly bent. Because the bending appeared to have occurred

Table 2. Results of a beam angle check from two check lines over a reference surface at Blue Springs Lake, Missouri, on March 18, 2010.

[ft, feet; <, less than: --, no data]

Beam angle Maximum Mean Standard 95 percent limit outlier difference deviation confidence (degrees) (ft) (ft) (ft) (ft) 20 0.85 0 0.10 0.20 25 .85 0 .10 .16 30 .85 0 .10 .16 35 .85 0 .10 .16 40 .85 0 .10 .16 45 .92 0 .10 .16 50 .92 0 .10 .16 55 .92 0 .10 .16 60 1.02 0 .10 .20 65 1.77 -.03 .13 .26 70 1.77 -.03 .16 .30

Performance standardsa 1.00 < .20 -- < .50 Within standards Yes, < 60 degrees Yes -- Yes

aPerformance standard check values are from U.S. Army Corps of Engineers (2004b), table 3–1. Equipment and Methods Used in Bathymetric Surveys 9

A Latency ∆t B Roll

C Pitch D Yaw

β δ

EXPLANATION Actual bottom Measured bottom ∆t Timing offset for latency between the multibeam echo sounder and Global Position System components of the navigation and motion-sensing 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

FigureFigure 6. 6. Effects ofof timing(A) timing and angularoffset for offsets latency, for Aand, latency, angular B, offsetsroll, C, pitch, for (B and) roll, D , (yawC) pitch, on data and from (D) yawa multibeam on data echofrom a sounder. multibeam echo sounder.

Table 3. Results of patch tests performed each day of surveying on the Missouri River in Kansas City, Missouri, and at Blue Springs Lake, Missouri.

[sec, seconds; deg, degrees; IS, Interstate highway; US, U.S. highway; MO, State highway]

Angular Angular Angular Timing offset for offset for offset for Date of test offset Location roll pitch yaw (sec) (deg) (deg) (deg) 03/15/10 0 0.21 -1.80 2.80 Missouri River in Kansas City, between IS 635 and US 69 03/16/10 0 .23 -1.80 2.50 Missouri River in Kansas City, between US 169 and MO 9 03/17/10 0 .25 -1.80 2.50 Missouri River in Kansas City, between MO 269 and IS 435 03/18/10 0 .29 -1.80 2.50 Blue Springs Lake, Missouri 10 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 gradually, the angular offset for roll value obtained during the Results of Bathymetric Surveys patch test on a given day was assumed to apply to all the data collected on that day. Using an average angular offset for roll The bathymetric data were processed to apply the patch value for each day (rather than an average value for the 4 days test corrections for each day of surveying and to remove data of surveying) minimized any error in the head position intro- spikes and other spurious points in the multibeam swaths. The duced by the bending mount. The daily values are consistent bathymetric data were then projected to a three-dimensional with angular offset for roll values determined for this boat dur- grid at a resolution of 0.82 ft (high resolution) near the bridge ing previous surveys (Richard Huizinga, unpub. data, 2010). pier(s) and 3.28 ft (low resolution) for the remainder of the A pitch test measures the angular offset of the transducer surveyed area. The bathymetric data were used to generate a head in a forward or aft direction along the lateral axis of the TIN of the channel bed in the vicinity of each bridge using boat, β (fig. 6C), which leads to horizontal position errors of ArcGIS. At structure A1800 on Interstate 635, structure A4060 a measured channel-bed point. In a pitch test, a line that is perpendicular to a slope or distinct feature on the channel bed on State Highway 9, and structure A0767 on Interstate 435, is surveyed twice in opposite directions at the same speed. the higher resolution data around the main channel piers were An angular offset for pitch error will appear as a horizontal obtained with a tilted transducer head after all the other chan- offset in the slope or feature between the reciprocal lines. For nel bathymetric data were obtained for that day. This time the March 2010 surveys, the measured angular offset for pitch difference resulted in a difference in the channel-bed eleva- equaled a constant value of -1.80° (table 3), which is consis- tions between the data sets, which is most noticeable along the tent with the angular offset for pitch value determined for this boundary between the data sets. boat during a previous survey (Richard Huizinga, unpub. data, The site-specific results for each bridge are discussed in 2010). The bending of the mount did not appear to affect the the following sections starting with the upstream-most bridge angular offset for pitch. site and progressing downstream, followed by a discussion of A yaw test measures the angular offset of the transducer general findings that are not site specific. All discharge values head in terms of its rotation about the vertical axis, δ (fig. D6 ), are from the USGS streamgage on the Missouri River at Kan- which results in horizontal position errors of a measured chan- sas City, Missouri (station 06893000), located on the down- nel-bed point for points in the outer beams. In a yaw test, two stream side of the Second Hannibal railroad bridge (fig. 1). All lines perpendicular to a slope or distinct feature on the channel elevation data were referenced to the North American Vertical bed are surveyed in the same direction at the same speed. An Datum of 1988 (NAVD 88). The difference between NAVD 88 angular offset for yaw error will appear as a horizontal offset and the National Geodetic Vertical Datum of 1929 (NGVD 29) in the slope or feature in the area between the surveyed lines. used in MoDOT bridge plans ranged from 0.26 to 0.28 ft For the March 2010 surveys, the measured angular offset for (NAVD 88 minus NGVD 29) throughout the Kansas City area, yaw was 2.80° on the first day of surveying, and was 2.50° for with an average value of 0.27 ft. the other days (table 3). These values are somewhat incon- At seven of the nine bridges, a Level II scour assessment sistent with angular offset for yaw values determined for this (Lagasse and others, 1991) was performed in 2002 (Huizinga boat during previous surveys (Richard Huizinga, unpub. data, and Rydlund, 2004). A Level II scour assessment is an applica- 2010), and likely is the result of the bending mount. How- tion of hydrologic, hydraulic, and sediment transport concepts ever, a sensitivity analysis of the four offsets implied that the to determine qualitative scour-depth estimates, and includes ultimate position of surveyed points in three-dimensional obtaining the cross section of the channel on the downstream space was least sensitive to the angular offset for yaw, whereas side of the bridge. The surveyed channel bed from this study it was most sensitive to the angular offset for roll (HYPACK, was compared to the channel bed at the time of the Level II Inc., 2009). assessment in 2002, where applicable. Results of Bathymetric Surveys 11

Structure A1800 on Interstate 635 large dune features were detected in the middle of the channel, as well as a localized deep hole in the middle of the down- Structure A1800 is on Interstate 635 on the northwest- stream channel (fig. 8). Numerous smaller dunes and ripples ern side of Kansas City, Missouri (figs. 1, 7). The survey was were along the left (north) bank on the inside of the river bend conducted on March 15, 2010, and the average water-surface and in the channel thalweg on the right (south) side (fig. 8). elevation of the river in the survey area determined by the In the vicinity of the main channel pier (pier 3, fig. 9), a RTK GPS tide solution was 734.83 ft (table 4). Flow on the scour hole had a minimum elevation of about 693 ft (table 4), Missouri River was about 129,000 ft3/s during the survey about 18 ft below the average channel bed immediately (table 4). upstream from the pier and 9 ft below the elevation of the The survey area was about 1,640 ft long and about bottom of the pier seal course of 702.28 ft (fig. 10; table 5). 700 ft wide, extending from bank to bank in the main channel Information from bridge plans indicates that the main chan- (fig. 8). The upstream end of the survey area was about 720 ft nel pier of structure A1800 is founded on shafts drilled 20 ft upstream from the centerline of structure A1800 (figs. 7, 8). into bedrock, with about 41 ft of bed material between the The channel-bed elevations ranged from about 694 to 728 ft. bottom of the scour hole and bedrock (table 5). A point cloud A deep thalweg along the outside of the river bend on the right visualization of the multibeam depth points obtained during (south) bank was about 25 ft deeper than the channel bed on the survey indicated the bottom of the seal course as a sonic the inside of the bend on the left (north) bank (fig. 8). Several “shadow” (fig. 11).

Structure A1800 on Interstate 635.

Table 4. Bridge and survey information and minimum elevations in the channel and scour holes from surveys on the Missouri River in Kansas City, Missouri, from March 15–18, 2010.

[MoDOT, Missouri Department of Transportation; ft3/s, cubic feet per second; ft, feet; IS, Interstate highway; US, U.S. highway; MO, State highway; all elevations are in feet above the North American Vertical Datum of 1988]

Average water- Approximate Approximate MoDOT surface elevation minimum MoDOT minimum Survey River Dischargea structure Route in vicinity of channel pier elevation in date mile (ft3/s) number bridge elevationb number scour holec (ft) (ft) (ft) A1800 03/15/10 IS 635 374.09 129,000 734.83 694 3 693 K0456/A0450 03/15/10 US 69 372.58 129,000 733.67 688 7/9 672 A4649 03/16/10 US 169 366.20 127,000 727.85 685 2 675 A4060 03/16/10 MO 9 365.52 126,000 727.05 688 6 689 5 691 A5817 03/17/10 MO 269 362.25 124,000 724.05 679 2 685 A0767 03/17/10 IS 435 360.26 123,000 722.52 682 7 679 A4757/L0568 03/18/10 MO 291 352.73 120,000 717.20 676 2C/5 661

aDischarge at the streamgage on the Missouri River at Kansas City, Missouri (station 06893000) at the time of the survey. bThe minimum channel elevation excluding scour holes near the bridge, typically in the channel thalweg. cThe point of lowest elevation in the scour hole near the bridge pier, not necessarily at the upstream pier face. 12 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

94°39'15" 94°39'10" 94°39'05" 94°39' 94°38'55" 94°38'50" 94°38'45"

39°09'25"

39°09'20"

Area of bathymetric survey shown in figure 8

39°09'15" Area of bathymetric survey shown in Structure figure 9 A1800

39°09'10"

39°09'05"

Base from National Agricultural Imagery Program, 2007 0 100 200 300 400 500 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) 0 50 100 150 METERS

Figure 7. Bathymetric survey area on the Missouri River near structure A1800 on Interstate 635 in Kansas City, Missouri. Figure 7. Location of the bathymetric survey area on the Missouri River near structure A1800 on Interstate 635 in Kansas City, Missouri. 12 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 13

94°39'10" 94°39'05" 94°38'55" 94°38'50"

94°39'

EXPLANATION

Channel-bed elevation, A in feet above NAVD 88 728 39°09'20" 726 724 722 Small dunes and ripples 720 718 Dunes and ripples 716 714 Medium dune features 712 710 708 The higher resolution data around 706 the pier were obtained with a tilted 704 transducer head after all the other 702 bathymetric data were obtained for 700 that day, resulting in a difference in 698 FLOW channel-bed elevations between the 696 high and low resolution data sets. Pier 3 694 This difference is most noticable 692 along the boundary between the data sets. Localized deep hole

Area of bathymetric Large dune features survey shown in figure 9 N Dunes and ripples

39°09'15"

Cross section shown in figure 10

Survey Date March 15, 2010 Discharge 129,000 cubic feet per second A' (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 734.83 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 50 100 150 200 250 FEET Universal Transverse Mercator projection, Zone 15 39°09'10" Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) 0 25 50 75 METERS Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88)

FigureFigure 8. 8. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structure A1800 on Interstate 635 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structure A1800 on Interstate 635 in Kansas City, Missouri. 14 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 15

94°39'04" 94°39'03" 94°39'02" 94°39'01" 94°38'59"

94°39'

EXPLANATION

Channel-bed elevation, in feet above NAVD 88 728 710 726 724 722 720 718 716 714 712 700 710 710 708 706 704 702 700 698 39°09'16" A 696 Longitudinal section

700 694 FLOW shown in figure 43A 700 692

710 Topographic contour— A' Pier 3 Shows channel-bed elevation, in feet above NAVD 88. 710 Contour interval is 2 feet

The higher resolution data around the pier were obtained with a tilted transducer head after all the other 700 bathymetric data were obtained for that day, resulting in a difference in N channel-bed elevations between the high and low resolution data sets. This difference is most noticable 39°09'15" along the boundary between the data sets. Subtle “steps” and waves likely caused by dune movement Survey Date March 15, 2010 into and around the scour hole Discharge 129,000 cubic feet per second 710 (based on discharge at streamflow-gaging station at Kansas City) 710 Average water-surface elevation 734.83 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 Universal Transverse Mercator projection, Zone 15 39°09'14" FEET Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS

FigureFigure 9. 9. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A1800 on Interstate 635 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the main channel pier of structure A1800 on Interstate 635 in Kansas City, Missouri. Results of Bathymetric Surveys 15 A' Footing

Column Cap Pier 2 Pier 1,150 1,200 1,250 1,300 1,350 1,400 Average water surface at time of survey (734.83 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface (1965) Approximate top of bedrock (from core logs) 1,100 Survey is along cross-section line shown in figure 8, facing downstream. 1,050 950 1,000 Seal course Footing Drilled shafts

Column Cap Pier 3 Pier PART OF BRIDGE SHOWN ABOVE 850 900 DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 750 800 650 700 Seal course Footing Drilled shafts

Column Cap Pier 4 Pier A 550 600

850 825 800 775 750 725 700 675 650 625 600 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 10. Key features, substructural and superstructural details, surveyed channel bed of structure A1800 on Interstate 635 over t he Missouri River in Kansas City, Missouri. Figure 10. Key features, substructural and superstructural details, surveyed channel bed of structure A1800 on Interstate 635 over the Missouri River in Kansas City, Missouri. 16 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 -- -- b c 2.03 2.45 (ft/ft) a frontal slope Approximate of scour hole 6 b 11 21 24 1.89 25 2.49 1516 1.91 2.06 21 28 2.00 18 1.77 (ft) upstream hole from channel bed Depth of scour 5 8 (ft) 50 19 47 19 24 42 45 41 Approximate bottom of scour hole and bedrock distance between (ft) bedrock elevation of Approximate (ft) 668 618 675 670 681 639 672 627 scour hole elevation of Approximate ------(ft) 689.26 679 660 bottom elevation Seal course (ft) into bedrock Penetration (ft) Width Foundation information Type pier MoDOT number Scour hole at this pier is substantially affected by upstream pier and apparent cobble-sized material on channel bed near the pier. Scour hole at this pier is substantially affected Scour hole at this pier is substantially affected by upstream pier. Scour hole at this pier is substantially affected by upstream pier skewed to approach flow; unable reasonably determine frontal slope. Scour hole at this pier is substantially affected a b c MoDOT number structure A4060 6 Drilled shaft 34 20 696.26 689 670 A4757 2C Drilled shaft 35 20 666.26 666 619 L0568 5 Caisson 20 2 A4649 2 Caisson 24 1 A4060 5 Drilled shaft 28 20 696.26 691 667 A5817A0767 2 7 Drilled shaft Drilled shaft 24 32 20 20 687.26 685 677 A0450 9 Caisson 22 5 A1800 3 Drilled shaft 28 20 702.28 693 652 K0456 7 Caisson 18 2 Table 5. Table Missouri, from March 15–18, 2010. Results at upstream pier faces from surveys on the Missouri River in Kansas City, 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 Surveys 17

EXPLANATION Elevation of point, in feet above the North American Vertical Datum of 1988 722 720 718 716 714 712 710 708 706 704 702 700 698 696 694 692

Flow

Photograph as shown is a reversal of actual photograph of the pier from the south side, and is shown for visualization Sonic “shadow” indicating purposes only. undermining of the seal course

Figure 11. 11. PointPoint cloud cloud visualization visualization of the of channel the channel bed and bed left and (north) left side (north) of the side main of channel the main pier channel of structure pier A1800 of on Interstate structure 635 A1800 over the on MissouriInterstate River 635 in overKansas the City, Missouri Missouri. River in Kansas City, Missouri. 18 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

Structures K0456 and A0450 on U.S. Highway 69 A localized deep hole was downstream from the upstream spur dike (fig. 13). Several large dune features were detected in the Structures K0456 and A0450 are dual bridges on middle of the channel, as well as numerous smaller dunes and U.S. Highway 69 on the northwestern side of Kansas City, ripples throughout the channel, particularly downstream from Missouri (figs. 1, 12). The survey was conducted on March the rock spur dikes and the main channel piers (fig. 13). 15, 2010, and the average water-surface elevation of the river In the vicinity of the main channel pier of upstream in the survey area determined by the RTK GPS tide solution structure K0456 (pier 7; fig. 14), a scour hole had a minimum was 733.67 ft (table 4). Flow on the Missouri River was about elevation of about 672 ft (table 4), about 28 ft below the aver- 129,000 ft3/s during the survey (table 4). age channel bed immediately upstream from the pier. The The survey area was about 1,640 ft long and about 710 ft scour hole upstream from pier 7 of upstream structure K0456 wide, extending from bank to bank in the main channel (fig. 13). was about 9 ft deeper than the scour hole upstream from pier 9 The upstream end of the survey area was about 640 ft upstream of downstream structure A0450 (table 5). from the centerline between structures K0456 and A0450 Information from bridge plans indicates that the main (figs. 12, 13). The channel-bed elevations ranged from about channel piers of both structures K0456 and A0450 are cais- 688 to 720 ft for most of the channel bed, except near the main sons on bedrock (figs. 15, 16). About 45 ft of bed material channel piers. A broad, shallow thalweg along the outside of the was between the bottom of the deeper scour hole at structure river bend on the right (south) bank was about 5 ft deeper than K0456 and the bottom of the caissons (fig. 15; table 5). The the channel bed in the middle of the channel (fig. 13). Between surveyed channel bed was about 18 ft deeper than the chan- the rock spur dikes on the inside of the bend on the left (north) nel bed from the Level II scour survey in 2002 along the right bank, deposits reached an elevation of about 722 ft (fig. 13). (south) bank (figs. 15, 16).

Structures K0456 and A0450 on U.S. Highway 69. Structure A0450 is in the foreground and K0456 is in the background. Results of Bathymetric Surveys 19

94°37'35" 94°37'30" 94°37'25" 94°37'20" 94°37'15" 94°37'10"

39°09'35"

39°09'30"

Area of bathymetric survey Structure shown in figure 13 Structure A0450 39°09'25" K0456

Area of bathymetric 39°09'20" survey shown in figure 14

39°09'15"

39°09'10"

Figure 12.Figure Location 12. Location of the bathymetric of the bathymetric survey area survey on the area Missouri on the RiverMissouri near River structures near structuresK0456 and A0450K0456 on and U.S. A0450 Highway on 69 in KansasU.S. City, Highway Missouri. 69 in Kansas City, Missouri. 20 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 21

39°09'25" 39°09'30"

94°37'30" 94°37'25" 94°37'20" 94°37'15"

EXPLANATION A Channel-bed elevation, B in feet above NAVD 88 726 Localized hole 724 722 720 718 Rock spur dike 716 714 712 710 708

Rock spur dike 706 704 702 700 Cross section shown in figure 16 Cross section shown in figure 17 698 696 694 692 FLOW 690 688 K0456 Pier 7 A0450 686 Pier 9 684 39°09'20" 682 680 678 676 674 672 Area of bathymetric 670 survey shown in figure 14

Survey Date March 15, 2010 Discharge 129,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) A' B' Average water-surface elevation 733.67 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 50 100 150 200 250 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) 0 25 50 75 METERS Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88)

FigureFigure 13. 13. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri. 20 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 21

39°09'24" 39°09'25"

94°37'26" 94°37'25" 94°37'24" 94°37'23" 94°37'22"

700 EXPLANATION Channel-bed elevation, in feet above NAVD 88 726 724 700 722 720 718 716 714 39°09'23" 690 712 710 700 708 706 704 702 Longitudinal section 680 700 700 shown in figure 43B 698 700 Longitudinal section 696 A 690 694 shown in figure 43C 692 680 B A' K0456 Pier 7 690 688 B' A0450 Pier 9 686 684 682 680 678 676 674 672 670

710700 Topographic contour— 39°09'22" 690 Shows channel-bed elevation, in feet above NAVD 88. Contour interval is 2 feet

FLOW

700 Survey Date March 15, 2010 N Discharge 129,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 733.67 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) 0 5 10 15 20 METERS 94°37'21" Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88)

Figure Figure 14.14. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the main channel piers of structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the main channel piers of structures K0456 and A0450 on U.S. Highway 69 in Kansas City, Missouri. 22 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 A'

Caisson Pedestal Column Pier 6 Pier 1,900 2,000 1,700 1,800 Survey is along cross-section line shown in figure 13, facing downstream.

Caisson

Pedestal Column 1,500 1,600 Pier 7 Pier PART OF BRIDGE SHOWN ABOVE 1,300 1,400 DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM Average water surface at time of survey (733.67 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/05/2002) Approximate land surface (1933) Approximate top of bedrock (from core logs) 1,100 1,200

Caisson

Pedestal Column Pier 8 Pier 1,000 A 900

875 850 825 800 775 750 725 700 675 650 625 600 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 15. Key features, substructural and superstructural details, surveyed channel bed of structure K0456 on U.S. Highway 69 over the Missouri River in Kansas City, Missouri. Figure 15. Key features, substructural and superstructural details, surveyed channel bed of structure K0456 on U.S. Highway 69 over the Missouri River in Kansas Missouri. City, Results of Bathymetric Surveys 23 B'

Caisson

Pedestal Column Pier 8 Pier 1,900 2,000 1,700 1,800 Survey is along cross-section line shown in figure 13, facing downstream. Caisson

Pedestal Column 1,500 1,600 Pier 9 Pier PART OF BRIDGE SHOWN ABOVE 1,300 1,400 DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM Average water surface at time of survey (733.67 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/05/2002) Approximate land surface (1956) Approximate top of bedrock (from core logs) 1,100 1,200 Caisson

Pedestal Column Pier 10 Pier 1,000 B 900

875 850 825 800 775 750 725 700 675 650 625 600 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 16. Key features, substructural and superstructural details, surveyed channel bed of structure A0450 on U.S. Highway 69 over the Missouri River in Kansas City, Missouri. Figure 16. Key features, substructural and superstructural details, surveyed channel bed of structure A0450 on U.S. Highway 69 over the Missouri River in Kansas Missouri. City, 24 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

Structure A4649 on U.S. Highway 169 and small dunes and ripples were detected throughout the channel, particularly in the channel thalweg upstream and down- Structure A4649 is on U.S. Highway 169, immediately stream from structure A4649 and between the highway bridge north of downtown Kansas City, Missouri (figs. 1, 17). The and the railroad bridge (fig. 18). survey was conducted on March 16, 2010, and the average In the vicinity of the main channel pier (pier 2; fig. 19), a water-surface elevation of the river in the survey area deter- scour hole had a minimum elevation of about 675 ft (table 4), mined by the RTK GPS tide solution was 727.85 ft (table 4). about 24 ft below the average channel bed immediately Flow on the Missouri River was about 127,000 ft3/s during the upstream from the pier (table 5). The scour hole was about 2 ft survey (table 4). deeper on the right (south) side than the north side, and the The survey area was about 1,800 ft long and about 820 ft hole extended further around on the right side (fig. 19). A sub- wide, extending from bank to bank in the main channel (fig. 18). merged remnant of a structure near the left downstream side of The upstream end of the survey area was about 820 ft upstream the pier (fig. 19) was presumably a nose for the railroad bridge from the centerline of structure A4649 at pier 2 (figs. 17, 18). downstream similar to the concrete nose upstream from the The channel-bed elevations ranged from about 685 to 708 ft for railroad bridge turntable pier. The remnants of the old bridge most of the channel bed, except near the main channel pier of piers were clearly defined, as were the piles of cobble-size structure A4649 and the various railroad bridge piers and con- debris around them. The remnant downstream from the exist- crete noses upstream from them (figs. 18, 19). A deep thalweg ing railroad bridge turntable pier had a maximum elevation on the right (south) bank on the upstream end of the surveyed of over 710 ft (fig. 19), which was only 17 ft below the water area was about 20 ft deeper than the channel bed in the middle surface on the day of the survey. Avoiding this pier remnant of the channel (fig. 18). The thalweg was shallower and shifted would be difficult in lower flow conditions than those on the to the middle of the channel at the bridges and downstream day of the survey. (fig. 18). Upstream from the rock spur dike on the inside of the Information from bridge plans indicate that the main bend on the upstream left (north) bank, deposits reached an channel pier structure A4649 is a caisson on bedrock, but only elevation of about 720 ft (fig. 18). Remnants of piers from an about 5 ft of bed material was between the bottom of the scour old bridge (presumably the first Hannibal railroad bridge) were hole and the bottom of the caissons (fig. 20; table 5). The sur- evident downstream from the existing Second Hannibal railroad veyed channel bed was approximately the same as the channel bridge (fig. 18). Unlike the two upstream sites (structure A1800 bed from the Level II scour survey in 2002 near the thalweg and structures K0456 and A0450), large dune features were not on the right (south) side of the channel, but was about 25 ft detected in the channel at this site; however, numerous medium deeper in mid-channel (fig. 20).

Structure A4649 on U.S. Highway 169. Results of Bathymetric Surveys 25

94°35'35" 94°35'30" 94°35'25" 94°35'20" 94°35'15" 94°35'10"

39°06'55"

39°06'50"

Second Hannibal (railroad bridge) Area of bathymetric survey shown in figure 18 Area of bathymetric survey shown in figure 19 39°06'45"

Structure A4649 39°06'40" U.S. Geological Survey streamflow- gaging station on the Missouri River at Kansas City, station 06893000

39°06'35"

Figure 17.Figure Location 17. Location of the bathymetric of the bathymetric survey area survey on the area Missouri on the RiverMissouri near River structure near A4649 structure on U.S. A4649 Highway on U.S. 169 Highway in 169 Kansasin City, Kansas Missouri. City, Missouri. 26 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 27

39°06'45" 39°06'50"

94°35'30" 94°35'25" 94°35'20" 94°35'15"

EXPLANATION

Channel-bed elevation, A in feet above NAVD 88 722 720 718 716 714 712 Remnants of old 710 railroad bridge 708 piers 706 704 702 700 Rock spur dike 698 696 694 692 A4649 Railroad bridge 690 Pier 2 pier 688 686 FLOW 684 682 39°06'40" Remnant of old railroad bridge 680 pier 678 676 Railroad bridge turn- 674 table pier Concrete nose for railroad bridge turntable pier Area of bathymetric survey shown in figure 19 Remnant of old railroad bridge turntable pier N

Railroad bridge pier Cross section shown in figure 20 Survey Date March 16, 2010 Discharge 127,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) A' Average water-surface elevation 727.85 feet above NAVD 88

FigureFigure 18. 18. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structure A4649 on U.S. Highway 169 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structure A4649 on U.S. Highway 169 in Kansas City, Missouri. 26 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 27

39°06'46" 39°06'47" 39°06'45" 94°35'24" 94°35'23" 94°35'22" 94°35'21" 94°35'20" 94°35'19" EXPLANATION Remnant of old nose 700 690 for railroad pier Remnant of old bridge pier Channel-bed elevation, 680 in feet above NAVD 88 722 680 Railroad bridge pier A Longitudinal section 720 shown in figure 43D 718 716 A' 714

680 A4649 Pier 2 690 712 680

690 710 708 706 704 702 700 698 680 696 694 39°06'44" 692 690 690 690 688 686 684 682 680 678 700 676 FLOW 674 690 690 690 690 Topographic contour— 690 Shows channel-bed elevation, in feet above NAVD 88. Remnant of old bridge pier Contour interval is 700 2 feet

710 710

690 690

39°06'43"

700 N

Concrete 690 Survey Date March 16, 2010 nose for rail- Railroad bridge 690 road bridge Discharge 127,000 cubic feet per second turntable pier (based on discharge at streamflow-gaging station at Kansas City) turntable pier Average water-surface elevation 727.85 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS 94°35'18"

FigureFigure 19. 19. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A4649 on U.S. Highway 169 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the main channel pier of structure A4649 on U.S. Highway 169 in Kansas City, Missouri. 28 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 A'

Caisson

Column Cap Pier 1 Pier Average water surface at time of survey (727.85 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/05/2002) Approximate land surface (1954) Approximate top of bedrock (from core logs) Survey is along cross-section line shown in figure 18, facing downstream.

Caisson

Column Cap Pier 2 Pier 1,100 1,050 1,150 1,200 1,250 1,300 1,350 1,400 1,450 1,500 1,550 1,600 1,650 1,700 PART OF BRIDGE SHOWN ABOVE DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 950 1,000 850 900 750 800

Caisson

Column Cap Pier 3 Pier 650 700 A 600

900 875 850 825 800 775 750 725 700 675 650 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 20. Key features, substructural and superstructural details, surveyed channel bed of structure A4649 on U.S. Highway 169 over the Missouri River in Kansas City, Missouri. Figure 20. Key features, substructural and superstructural details, surveyed channel bed of structure A4649 on U.S. Highway 169 over the Missouri River in Missouri. Kansas City, Results of Bathymetric Surveys 29

Structure A4060 on State Highway 9 A pile of cobble-sized material immediately upstream from pier 6 of structure A4060 appeared to extend around the right Structure A4060 is on State Highway 9, immediately (south) side (fig. 23), but it was about 1 ft below the eleva- north of downtown Kansas City, Missouri (figs. 1, 21). The tion of the bottom of the pier seal course of 696.26 ft (fig. 24; survey was conducted on March 16, 2010, and the average table 5). The minimum elevation in the vicinity of pier 6 was water-surface elevation of the river in the survey area deter- about 7 ft below the elevation of the bottom of the pier seal mined by the RTK GPS tide solution was 727.05 ft (table 4). course (figs. 23, 24; table 5). Information from bridge plans Flow on the Missouri River was about 126,000 ft3/s during the indicates that pier 6 is founded on shafts drilled 20 ft into survey (table 4). bedrock, with about 19 ft of bed material between the bottom The survey area was about 1,800 ft long and about of the scour hole and bedrock (fig. 24; table 5). A point cloud 810 ft wide, extending from bank to bank in the main channel visualization of the multibeam depth points obtained during (fig. 22). Piers 5 and 6 were in the water and away from the the survey indicates the bottom of the seal course as a sonic banks at structure A4060. The upstream end of the survey “shadow” (fig. 25). area was about 860 ft upstream from the centerline of struc- In the immediate vicinity of the left main channel pier ture A4060 at pier 6 (figs. 21, 22). The channel-bed elevations (pier 5; fig. 26), a scour hole had a minimum elevation of ranged from about 688 to 710 ft for most of the channel bed, about 691 ft (table 4), about 5 ft below the elevation of the except near the railroad bridge pier upstream from pier 6 of bottom of the pier seal course of 696.26 ft (fig. 24; table 5). structure A4060. A deep thalweg along the right (south) bank Information from bridge plans indicates that pier 5 also is throughout the surveyed area was about 20 ft deeper than founded on shafts drilled 20 ft into bedrock, with about 24 ft the channel bed in the middle of the channel (fig. 22). A few of bed material between the bottom of the scour hole and large dune features were detected in the middle of the channel bedrock (fig. 24; table 5). The point cloud visualization of upstream from the bridges, as well as numerous smaller dunes the multibeam depth points obtained during the survey does and ripples along the left (north) bank and in the channel not clearly indicate the bottom of the seal course as a sonic thalweg on the right (south) side (fig. 22). Upstream from “shadow” because the side of the seal course did not have as the rock spur dike on the upstream left (north) bank, deposits many return pings, resulting in poor point coverage. However, reached an elevation of about 714 ft (fig. 22). Downstream the difference in elevation between the top of the seal course from structure A4060, the elevations in the middle of the and bed can be seen, and is greater than the depth of the seal channel were 5 to 8 ft lower than elevations upstream from course (fig. 27). Several beams or piles protruded from the the bridges. channel bed immediately upstream from pier 5 (fig. 26). Near the right main channel pier (pier 6; fig. 23), a poorly The surveyed channel bed was about the same as the defined scour hole had a minimum elevation of about 689 ft; channel bed from the Level II scour survey in 2002 on the however, a substantial scour hole immediately upstream from left (north) side and middle of the channel except near pier 5 the pier had a minimum elevation of about 679 ft. This deeper (fig. 24). Near the thalweg on the right (south) side of the hole appeared to be the result of flow over large sheet pil- channel, the surveyed channel was about 15 ft deeper than ing panels that were lying on the channel bottom on the right during the Level II scour survey in 2002, but was similar to (south) side of the upstream railroad bridge pier (fig. 23). the channel configuration from 1981 (fig. 24).

Structure A4060 on State Highway 9. 30 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

94°35' 94°34'55" 94°34'50" 94°34'45" 94°34'40" 94°34'35" 94°34'30" 39°07'15"

39°07'10"

39°07'05" Area of bathymetric survey shown in figure 26 Area of bathymetric survey shown in figure 22 Area of bathymetric survey shown in figure 23 39°07'

Structure A4060

ASB (railroad bridge) 39°06'55"

39°06'50"

Figure Figure21. Location 21. Location of the bathymetricof the bathymetric survey areasurvey on areathe Missouri on the MissouriRiver near River structure near A4060structure on State A4060 Highway on State 9 inHighway Kansas 9 City, Missouri.in Kansas City, Missouri. 30 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 31

39°07'05"

94°34'55" 94°34'50" 94°34'45" 94°34'40" EXPLANATION

A Channel-bed elevation, in feet above NAVD 88 39°07' 720 Railroad bridge pier 718 716 714 712 710 708 A4060 Pier 5 706 704 702

Rock spur dike Area of bathymetric 700 survey shown in 698 figure 26 696 694 692 690 The higher resolution data around 688 FLOW the pier were obtained with a tilted 686 transducer head after all the other 684 bathymetric data were obtained for 682 that day, resulting in a difference in 680 channel-bed elevations between the Railroad bridge pier A4060 Pier 6 high and low resolution data sets. This difference is most noticable along the boundary between the data sets.

39°06'55" N Area of bathymetric survey shown in figure 23

Cross section shown in figure 24

Survey Date March 16, 2010 A' Discharge 126,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 727.05 feet above NAVD 88

FigureFigure 22. 22. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structure A4060 on State Highway 9 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structure A4060 on State Highway 9 in Kansas City, Missouri. 32 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 33

" 39°07' 39°07'01" 39°07'02"

94°34'44 94°34'49" 94°34'48" 94°34'47" 94°34'46" 94°34'45"

EXPLANATION

Channel-bed elevation, in feet above NAVD 88 FLOW 720 718 716 The higher resolution data around 714 the pier were obtained with a tilted 712 700 transducer head after all the other 710 bathymetric data were obtained for 708 706 that day, resulting in a difference in 704 channel-bed elevations between the 702 700 700 high and low resolution data sets. This difference is most noticable 698 39°06'59" 700 along the boundary between the 696 694 data sets. 692 700 690 688 686 684 710 710 Railroad bridge pier 682 690 680 690 A4060 Pier 6 700 710700 Topographic contour— Shows channel-bed elevation, in feet above NAVD 88. Contour interval is 690 2 feet

680 Cobble-sized material

39°06'58" Sheet piling panels N 700 690 that have fallen from 690 690 the side of the railroad bridge pier 700

Survey Date March 16, 2010 Discharge 126,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 727.05 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS 94°34'43" 94°34'42"

FigureFigure 23. 23. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the right main channel pier of structure A4060 on State Highway 9 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the right main channel pier of structure A4060 on State Highway 9 in Kansas City, Missouri. Results of Bathymetric Surveys 33 A' Seal course Piles Footing

Cap Column Pier 7 Pier Average water surface at time of survey (727.05 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/05/2002) Approximate land surface (1981) Approximate top of bedrock (from core logs) Survey is along cross-section line shown in figure 22, facing downstream. 1,150 1,200 1,250 1,300 1,350 1,400 1,450 1,500 1,550 1,600 Seal course Footing Drilled shafts

Cap Column Pier 6 Pier 1,100 1,050 PART OF BRIDGE SHOWN ABOVE 950 1,000 DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 850 900 Seal course Footing Drilled shafts

Column Cap Pier 5 Pier 750 800 700 650 Seal course Footing Drilled shafts

600 Cap Column Pier 4 Pier A 550

850 825 800 775 750 725 700 675 650 625 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 24. Key features, substructural and superstructural details, surveyed channel bed of structure A4060 on State Highway 9 over the Missouri River in Kansas City, Missouri. Figure 24. Key features, substructural and superstructural details, surveyed channel bed of structure A4060 on State Highway 9 over the Missouri River in Kansas Missouri. City, 34 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

EXPLANATION Elevation of point, in feet above the North American Vertical Datum of 1988 714 712 710 708 706 704 702 700 698 696 694 692 690

Flow

Photograph is of left main channel pier (pier 5) from the Approximate bottom of Sonic “shadow” indicating south side, and is shown for the seal course undermining of the seal course visualization purposes only.

Figure 25. Point cloud visualization of the channel bed and right (south) side of the right main channel pier Figure 25. Point cloud visualization of the channel bed and right (south) side of the right main channel pier (pier 6) of structure(pier 6) of A4060 structure on State A4060 Highway on State9 over Highwaythe Missouri 9 overRiver thein Kansas Missouri City, RiverMissouri. in Kansas City, Missouri. 34 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 35

39°07'04" 39°07'05"

94°34'49" 94°34'48" 94°34'47" 94°34'46" 94°34'45" EXPLANATION 710 Channel-bed elevation, 39°07'03" in feet above NAVD 88 710 720 710 718 Railroad bridge pier 700 716 700 714 712 The higher resolution data around 710 the pier were obtained with a tilted 708 transducer head after all the other 706 bathymetric data were obtained for 704 702 that day, resulting in a difference in 700 channel-bed elevations between the 698 700 high and low resolution data sets. 696 This difference is most noticable 694 along the boundary between the 692 690 data sets. FLOW 688 686 Beams or piles 684 682 39°07'02" Longitudinal section 700 680 706 706 shown in figure 43E

710700 Topographic contour— A A' A4060 Pier 5 700 Shows channel-bed elevation, in feet above NAVD 88. Contour interval is 2 feet 706

700 700

700 39°07'01" 700 Survey Date March 16, 2010 Discharge 126,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City)

700 Average water-surface elevation 727.05 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS 94°34'44" 94°34'43"

Figure Figure 26.26. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the left main channel pier of structure A4060 on State Highway 9 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the left main channel pier of structure A4060 on State Highway 9 in Kansas City, Missouri. 36 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

EXPLANATION Elevation of point, in feet above the North American Vertical Datum of 1988 714 712 710 708 706 704 702 700 698 696 694 692 690

Flow

Approximate bottom of the seal course The side of the seal course did not have as many return pings, possibly due to beam angles Sonic “shadow” below seal course indicating probable undermining of the seal course

Figure 27. Point cloud visualization of the channel bed and right (south) side of the left main channel pier Figure 27. Point cloud visualization of the channel bed and right (south) side of the left main channel pier (pier 5) of structure(pier 5) ofA4060 structure on State A4060 Highway on State9 over theHighway Missouri 9 overRiver thein Kansas Missouri City, RiverMissouri. in Kansas City, Missouri. Results of Bathymetric Surveys 37

Structure A5817 on State Highway 269 detected throughout the middle of the channel, as well as numerous smaller dunes and ripples along the right (south) Structure A5817 is on State Highway 269, northeast of bank (fig. 29); the lack of dunes in the thalweg near structure downtown Kansas City, Missouri (figs. 1, 28). The survey A5817 compared to those seen at several of the upstream was conducted on March 17, 2010, and the average water- bridge sites further substantiates the presence of rock outcrops surface elevation of the river in the survey area determined by in the thalweg near structure A5817. Two piles of coarse mate- the RTK GPS tide solution was 724.05 ft (table 4). Flow on rial downstream from structure A5817 appeared to be rem- the Missouri River was about 124,000 ft3/s during the survey nants of old piers. (table 4). In the vicinity of the main channel pier 2 (fig. 30), a scour The survey area was about 1,800 ft long and about hole had a minimum elevation of about 685 ft (table 4), about 920 ft wide, extending from bank to bank in the main chan- 1 ft below the elevation of the bottom of the pier seal course of nel (fig. 29). Piers 2 and 3 were in the water and away from 687.26 ft (fig. 31; table 5). Information from bridge plans indi- the banks at structure A5817; however, pier 3 was in shallow cates that pier 2 of structure A5817 is founded on shafts drilled water, and only limited bathymetric data could be obtained 20 ft into bedrock, with about 8 ft of bed material between the near it. The upstream end of the survey area was about 810 ft bottom of the scour hole and bedrock (fig. 31; table 5). A point upstream from the centerline of structure A5817 at pier 2 cloud visualization of the multibeam depth points obtained dur- (figs. 28, 29). The channel-bed elevations ranged from about ing the survey shows the potential minor undermining as a sonic 679 to 708 ft, except near the rock spur dike on the upstream “shadow” when the bottom of the seal course is shown (fig. 32). right (south) bank and near pier 3 (fig. 29). A deep thalweg The surveyed channel bed was about 8 to 10 ft lower than along the left (north) bank throughout the surveyed area the channel configuration from 1992 (fig. 31). The approxi- contained evidence of bedrock exposure, and was about mate top of bedrock line from bridge plans further substanti- 25 ft deeper than the channel bed in the middle of the chan- ates the likelihood of the channel thalweg having penetrated nel (fig. 29). Numerous medium to large dune features were the fluvial material to bedrock (fig. 31).

Structure A5817 on State Highway 269. 38 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

94°32'15" 94°32'10"W 94°32'05" 94°32' 94°31'55" 94°31'50"

39°08'55"

39°08'50"

Structure Area of bathymetric survey A5817 shown in figure 29 Area of bathymetric survey shown in figure 30

39°08'45"

39°08'40"

39°08'35"

39°08'30"

Figure Figure28. Location 28. Location of the bathymetric of the bathymetric survey area survey on thearea Missouri on the MissouriRiver near River structure near A5817structure on State A5817 Highway on State 269 Highway in 269 Kansas inCity, Kansas Missouri. City, Missouri. 38 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 39

39°08'50"

94°32'10" 94°32'05" 94°32' 94°31'55" A EXPLANATION

Channel-bed elevation, in feet above NAVD 88 39°08'45" 716 714 712 710 708 706 Exposed bedrock outcrops 704 702 700 698 696 Old pier remnant 694 692 690 688 FLOW 686 684 Pier 2 682 680 678

Area of bathymetric N survey shown in figure 30 39°08'40"

Old pier remnant

Rock spur dike

Too shallow around pier—no bathymetry data collected Cross section shown in figure Pier31 3

Survey Date March 17, 2010 Discharge 124,000 cubic feet per second A' (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 724.05 feet above NAVD 88

FigureFigure 29. 29. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structure A5817 on State Highway 269 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structure A5817 on State Highway 269 in Kansas City, Missouri. 40 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 41

39°08'47" 39°08'48" 39°08'46" 94°32'06" 94°32'05" 94°32'04" 94°32'03" 94°32'02" 94°32'01" EXPLANATION

Channel-bed elevation, 690 Old pier remnant in feet above NAVD 88 716 714 712 700 710 708 706 704 702 700 698 696 694 692 690 700 688 39°08'45" 686 700 690 684 682 700 680 A Longitudinal section 678 shown in figure 43F A' Pier 2 710700 Topographic contour— Shows channel-bed elevation, in feet above NAVD 88. 700 Contour interval is 2 feet

700 700 N FLOW

39°08'44"

700 700 Survey Date March 17, 2010 Discharge 124,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 724.05 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) 94°32' Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS 94°31'59"

Figure Figure 30.30. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A5817 on State Highway 269 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the main channel pier of structure A5817 on State Highway 269 in Kansas City, Missouri. Results of Bathymetric Surveys 41 A' Footing Seal course

Piles

Cap Pedestal Column Pier 4 Pier Seal course

Footing Drilled shafts

Pedestal Cap Column Pier 3 Pier Survey is along cross-section line shown in figure 29, facing downstream. 700 Seal course Footing Drilled shafts Cap Pedestal Column

650 750 800 850 900 950 1,000 1,050 1,100 1,150 1,200 1,250 1,300 1,350 Pier 2 Pier PART OF BRIDGE SHOWN ABOVE DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 550 600 450 500 Average water surface at time of survey (724.05 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface (1992) Approximate top of bedrock (from core logs) 350 400 300 250

Footing

Cap Pedestal Column Pier 1 Pier 200 A 150

825 800 775 750 725 700 675 650 625 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 31. Key features, substructural and superstructural details, surveyed channel bed of structure A5817 on State Highway 269 ove r the Missouri River in Kansas City, Missouri. Figure 31. Key features, substructural and superstructural details, surveyed channel bed of structure A5817 on State Highway 269 over the Missouri River in Kansas Missouri. City, 42 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

EXPLANATION

Elevation of point, in feet above the North American Vertical Datum of 1988 712 710 708 706 704 702 700 698 696 694 692 690 688 686

Flow

Photograph as shown is a Areas with erroneous points, reversal of actual photograph of the pier from the south side, removed during data editing process and is shown for visualization Approximate bottom of Sonic “shadow” indicating potential purposes only. the seal course undermining of the seal course

Figure 32. Point cloud visualization of the channel bed and left (north) side of the main channel pier of Figure structure 32. PointA5817 cloud on State visualization Highway of the 269 channel over thebed Missouriand left (north) River side in Kansasof the main City, channel Missouri. pier of structure A5817 on State Highway 269 over the Missouri River in Kansas City, Missouri. Results of Bathymetric Surveys 43

Structure A0767 on Interstate 435 the channel was filled with numerous large and small dune features as well as ripples along both banks (fig. 34). Down- Structure A0767 is on Interstate 435 on the northeast- stream from the rock spur dike on the right (south) bank near ern side Kansas City, Missouri (figs. 1, 33). The survey was structure A0767, deposits reached an elevation of about 717 ft conducted on March 17, 2010, and the average water-surface (fig. 34). elevation of the river in the survey area determined by the In the immediate vicinity of the main channel pier 7 RTK GPS tide solution was 722.52 ft (table 4). Flow on the (fig. 35), a scour hole had a minimum elevation of about 679 ft Missouri River was about 123,000 ft3/s during the survey (table 4), about 10 ft below the elevation of the bottom of the (table 4). pier seal course of 689.26 ft (fig. 36; table 5). Information The survey area was about 1,800 ft long and about from bridge plans indicates that pier 7 is founded on shafts 845 ft wide, extending from bank to bank in the main channel drilled 20 ft into bedrock, with about 19 ft of bed material (fig. 34). Piers 7 and 8 were in the water and away from the between the bottom of the scour hole and bedrock (fig. 36; banks at structure A0767; however, pier 8 was immediately table 5). A point cloud visualization of the multibeam depth downstream from a rock spur dike and was surrounded by a points obtained during the survey indicates the bottom of the substantial debris raft, and only limited bathymetric data could seal course as a sonic “shadow,” with the sides of drilled shafts be obtained near it (fig. 34). The upstream end of the survey appearing as points in the shadow (fig. 37). area was about 800 ft upstream from the centerline of struc- The surveyed channel bed was similar to the channel ture A0767 at pier 7 (figs. 33, 34). The channel-bed elevations bed from the Level II scour survey in 2002 for most of the generally ranged from about 682 to 708 ft, except downstream channel except along the left (north) bank, near pier 7, and from the tip of the rock spur dike, near an unidentified object along the spur dike near pier 8 (fig. 36). Part of this difference in the channel downstream from structure A0767, and near arises from the fact that the Level II survey line was along the pier 7 of structure A0767 (fig. 34). The channel thalweg was downstream face of structure A0767, whereas the bathymetric along the left (north) bank throughout the surveyed area, and survey cross-section line was along the upstream face.

Structure A0767 on Interstate 435. 44 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

94°30'05" 94°30' 94°29'55" 94°29'50" 94°29'45" 94°29'40"

39°09'10"

Area of bathymetric survey shown in 39°09'05" figure 35

Structure A0767

39°09' Area of bathymetric survey shown in figure 34

39°08'55"

39°08'50"

Figure 33.Figure Location 33. Location of the bathymetric of the bathymetric survey area survey on thearea Missouri on the RiverMissouri near River structure near A0767 structure on Interstate A0767 on 435 Interstate in Kansas 435 City, Missouri. in Kansas City, Missouri. 44 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 45

94°29'55" 94°29'50" 94°29'45" 94°29'40"

94°30'

A EXPLANATION Channel-bed elevation, Cross section shown in figure 36 in feet above NAVD 88 718 39°09'10" 716 714 712 710 708 706 704 702 700 698 696 694 692 690 688 686 684 682 Pier 7 680 Unidentified 678 submerged 676 objects

Area of bathymetric 39°09'05" survey shown in N figure 35 The higher resolution data around the pier were obtained with a tilted Rock spur dike transducer head after all the other FLOW bathymetric data were obtained for that day, resulting in a difference in channel-bed elevations between the 39°09' high and low resolution data sets. Pier 8 This difference is most noticable Debris raft— no bathymetry along the boundary between the collected data sets.

Survey Date March 17, 2010 Discharge 123,000 cubic feet per second A' (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 722.52 feet above NAVD 88

FigureFigure 34. 34. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structure A0767 on Interstate 435 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structure A0767 on Interstate 435 in Kansas City, Missouri. 46 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 47

94°29'55" 94°29'54" 94°29'53" 94°29'52" 94°29'51" 94°29'50"

EXPLANATION 690 Channel-bed elevation, in feet above NAVD 88 718 716 714 690 712 710 708 706 690 704 702 690 700 39°09'06" 690 698 696 694 692 690 690 688 686 684 682 680 680 678 676

690 690 690 Topographic contour— FLOW Pier 7 690 Shows channel-bed A' elevation, in feet above NAVD 88. Longitudinal section Contour interval is A shown in figure 43G 39°09'05" 2 feet

680 690 690 N

The higher resolution data around the pier were obtained with a tilted 680 transducer head after all the other bathymetric data were obtained for that day, resulting in a difference in Unidentified submerged Survey Date March 17, 2010 channel-bed elevations between the 690 high and low resolution data sets. object Discharge 123,000 cubic feet per second This difference is most noticable (based on discharge at streamflow-gaging station at Kansas City) along the boundary between the Average water-surface elevation data sets. 680 722.52 feet above NAVD 88 39°09'04" Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS

Figure Figure 35.35. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the main channel pier of structure A0767 on Interstate 435 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the main channel pier of structure A0767 on Interstate 435 in Kansas City, Missouri. Results of Bathymetric Surveys 47

A' Pier 9 Pier Cap Piles Seal Column Footing course 1,750 1,800 1,850 Seal course Footing Drilled shafts Column Cap

1,650 1,700 Pier 8 Pier Survey is along cross-section line shown in figure 34, facing downstream. Seal course Footing Drilled shafts

Column Cap Pier 7 Pier PART OF BRIDGE SHOWN ABOVE DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 1,150 1,200 1,250 1,300 1,350 1,400 1,450 1,500 1,550 1,600 1,100 1,050 Average water surface at time of survey (722.52 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/06/2002) Approximate land surface (1965) Approximate top of bedrock (from core logs) 950 1,000 Seal course Footing

Drilled shafts

Column Cap Pier 6 Pier A 850 900

825 800 775 750 725 700 675 650 625 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 36. Key features, substructural and superstructural details, surveyed channel bed of structure A0767 on Interstate 435 over t he Missouri River in Kansas City, Missouri. Figure 36. Key features, substructural and superstructural details, surveyed channel bed of structure A0767 on Interstate 435 over the Missouri River in Kansas City, Missouri. 48 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

EXPLANATION Elevation of point, in feet above the North American Vertical Datum of 1988 708 706 704 702 700 698 696 694 692 690 688 686 684 682

Flow

Photograph as shown is a reversal of actual photograph of the pier from the south side, Approximate bottom of Sonic “shadow” indicating Echo from sides of and is shown for visualization the seal course undermining of the seal course drilled shafts and debris purposes only. on upstream shaft Figure 37. Point cloud visualization of the channel bed and left (north) side of the main channel pier of Figure structure 37. A0767 Point cloud on Interstate visualization 435 of theover channel the Missouri bed and Riverleft (north) in Kansas side of theCity, main Missouri. channel pier of structure A0767 on Interstate 435 over the Missouri River in Kansas City, Missouri. Results of Bathymetric Surveys 49

Structures A4757 and L0568 on State right (south) end of pier 2C of structure A4757 and to the right Highway 291 (south) of pier 5 of structure L0568 (fig. 40). At the upstream end of pier 2C of structure A4757, the minimum elevation Structures A4757 and L0568 are dual bridges on State was about 666 ft, and at the upstream end of pier 5 of struc- Highway 291 on the northeastern side of Kansas City, Mis- ture L0568, the minimum elevation was about 668 ft (fig. 40; souri (figs. 1, 38). The survey was conducted on March 18, table 5). The point of minimum elevation near each pier 2010, and the average water-surface elevation of the river in occurred at the downstream right (south) side of both piers, the survey area determined by the RTK GPS tide solution was and was about 665 ft for structure A4757 and about 663 ft for 717.20 ft (table 4). Flow on the Missouri River was about structure L0568 (fig. 40). 120,000 ft3/s during the survey (table 4). Information from bridge plans indicates that the main The survey area was about 1,780 ft long and about channel pier of structure A4757 is founded on shafts drilled 810 ft wide, extending from bank to bank in the main chan- 20 ft into bedrock, with about 47 ft of bed material between nel (fig. 39). The upstream end of the survey area was about the bottom of the scour hole and bedrock at the upstream end 740 ft upstream from the centerline between structures A4757 of the pier (fig. 41; table 5), and about 46 ft of bed material and L0568 (figs. 38, 39). The channel-bed elevations ranged between the bottom of the hole and bedrock at the point of from about 676 to 702 ft for most of the channel bed, except minimum elevation at the downstream end of the pier. At the near the main channel piers of structures A4757 and L0568. A point of minimum elevation, the surveyed channel bed was narrow channel thalweg was along the left (north) bank at the about 1 ft lower than the bottom of the seal course elevation of upstream end of the surveyed area that widened throughout the 666.26 ft (table 5). The surveyed bed was about 15 ft deeper surveyed area (fig. 39). A few large dune features were detected than the channel bed from the Level II scour survey in 2002 on in the channel upstream from the bridges, as well as numerous the left (north) side of the channel, and about 10 feet shallower smaller dunes and ripples along the right (south) bank upstream on the right (south) side, except near the right (south) bank from the bridge and across the channel downstream from the (fig. 41). bridges (fig. 39). A noticeable channel constriction was at and Information from bridge plans indicates that the main immediately downstream from the bridges. channel pier of structure L0568 is a caisson on bedrock In the vicinity of the main channel piers (fig. 40), a (fig. 42), with about 50 ft of bed material between the bottom large scour hole had a minimum elevation of about 661 ft of the scour hole and bedrock at the upstream end of the pier (table 4), about 25 ft below the average channel bed immedi- (fig. 42; table 5), and about 45 ft of bed material between the ately upstream from the piers. The main channel piers were bottom of the hole and bedrock at the point of minimum eleva- skewed to approach flow, which caused a wide scour hole tion at the downstream end of the pier. Similar to structure with somewhat unique characteristics as compared to scour A4757, the surveyed channel bed was about 15 ft deeper than holes at the other surveyed bridges. Pier 5 of structure L0568 the channel bed from the Level II scour survey in 2002 on the was in the wake of pier 2C of structure A4757, and, there- left (north) side of the channel and varied from about 10 ft fore, had no well-defined scour hole specific to it. The point deeper to 10 ft shallower on the right (south) side of the chan- of overall minimum elevation occurred downstream from the nel (fig. 42).

Structures A4757 and L0568 on State Highway 291. Structure L0568 is in the foreground and A4757 is in the background. 50 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

94°23'55" 94°23'50" 94°23'45" 94°23'40" 94°23'35" 94°23'30" 94°23'25"

39°10'15"

Area of bathymetric survey shown in figure 39

39°10'10"

Structure Structure L0568 A4757 Area of bathymetric survey shown in 39°10'05" figure 40

39°10'

39°09'55"

39°09'50"

Figure Figure38. Location 38. Location of the bathymetric of the bathymetric survey area survey on thearea Missouri on the MissouriRiver near River structures near structures A4757 and A4757L0568 onand State L0568 Highway on 291 in Kansas State HighwayCity, Missouri. 291 in Kansas City, Missouri. 50 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 51

0" 5" 0" 5"

39°10'10"

94°23'5 94°23'4 94°23'4 94°23'3 AB EXPLANATION Channel-bed elevation, in feet above NAVD 88 710 39°10'05" 708 706 704 702 700 698 696 694 Area of bathymetric 692 Cross section shown in figure 41 survey shown in Cross section shown in figure 42 690 figure 40 688 686 684 682 680 678

A 4757 Pier 2C L0568 Pier 5 676 674 FLOW 672 670 668 666 664 662 660

39°10'

A' B' Survey Date March 18, 2010 Discharge 120,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) Average water-surface elevation 717.20 feet above NAVD 88

FigureFigure 39. 39. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri. 52 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 Results of Bathymetric Surveys 53

39°10'06"

94°23'44" 94°23'43" 94°23'42" 94°23'41" 94°23'40" 94°23'39" EXPLANATION 39°10'05" Channel-bed elevation, in feet above NAVD 88 710 680 708 Subtle “steps” and waves 706 680 likely caused by dune movement 704 into and around the scour hole 702 700 698 696 694 692 A 690 Longitudinal section 688 shown in figure 43H 670 686 684 682 680 A’ 678 39°10'04" 676 A4757 Pier 2C L0568 Pier 5

680 680 674 670 672 670 668 670 666 664 662 690 660 680

690 Topographic contour— Shows channel-bed 670 elevation, in feet 670 above NAVD 88. Contour interval is 2 feet 680

680 39°10'03"

690 N FLOW Survey Date March 18, 2010 Discharge 120,000 cubic feet per second (based on discharge at streamflow-gaging station at Kansas City) 680 680 Average water-surface elevation 717.20 feet above NAVD 88

Base from National Agricultural Imagery Program, 2007 0 10 20 30 40 50 60 FEET Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 0 5 10 15 20 METERS 94°23'38"

FigureFigure 40. 40. Bathymetric Bathymetric survey of the Missouri River channel in the vicinity of the main channel piers of structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri. survey of the Missouri River channel in the vicinity of the main channel piers of structures A4757 and L0568 on State Highway 291 in Kansas City, Missouri. Results of Bathymetric Surveys 53

A' Pier 3C Pier Column Piles Pedestal Footing Seal course 1,350 1,400 1,450 1,250 1,300 Survey is along cross-section line shown in figure 39, facing downstream. Seal course Footing Drilled shafts

Pedestal Column Pier 2C Pier PART OF BRIDGE SHOWN ABOVE DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 750 800 850 900 950 1,000 1,050 1,100 1,150 1,200 700 650 Average water surface at time of survey (717.20 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/06/2002) Approximate land surface (1993) Approximate top of bedrock (from core logs) 550 600 Seal course Footing Drilled shafts

Pedestal Column Pier 1C Pier ey features, substructural and superstructural details, surveyed channel bed of structure A4757 on State Highway 291 over t he Missouri River in Kansas K A 450 500

850 825 800 775 750 725 700 675 650 625 600 575 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 41. Key features, substructural and superstructural details, surveyed channel bed of structure A4757 on State Highway 291 ove r the Missouri River in Kansas City, Missouri. Figure 41. City, Missouri. City, 54 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 B'

Caisson

Pedestal Column Pier 4 Pier 1,350 1,400 1,450 1,250 1,300 Survey is along cross-section line shown in figure 39, facing downstream.

Caisson

Pedestal Column Pier 5 Pier PART OF BRIDGE SHOWN ABOVE DISTANCE FROM FILL FACE OF LEFT (NORTH) ABUTMENT, IN FEET OF LEFT (NORTH) ABUTMENT, IN FILL DISTANCE FACE FROM 750 800 850 900 950 1,000 1,050 1,100 1,150 1,200 700 650 Average water surface at time of survey (717.20 feet above NAVD 88) Channel bed from multibeam survey Approximate land surface at time of Level II scour survey (11/06/2002) Approximate land surface (1946) Approximate top of bedrock (from core logs)

550 600 Pier 6 Pier Caisson Pedestal Column B 450 500

850 825 800 775 750 725 700 675 650 625 600 575 ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) (NAVD 1988 OF DATUM VERTICAL AMERICAN NORTH ABOVE FEET IN ELEVATION, Figure 42. Key features, substructural and superstructural details, surveyed channel bed of structure L0568 on State Highway 291 over the Missouri River in Kansas Missouri. City, Figure 42. Key features, substructural and superstructural details, surveyed channel bed of structure L0568 on State Highway 291 ove r the Missouri River in Kansas City, Missouri. Results of Bathymetric Surveys 55

General Findings and Implications hole that nearly encompassed the main channel piers of both bridges (figs. 39, 40). Although the piers of structure A4060 Several of the findings at each surveyed bridge were were aligned to the flow, the railroad bridge piers upstream common to all of the bridges, and some findings only appear from structure A4060 were skewed to flow (figs. 22, 23, 26), when the surveys are examined as a set. These general find- and the effects of the asymmetric scour hole upstream from ings are of benefit to the assessment of scour at the surveyed the right main channel pier (pier 6) affected the shape and size bridges, as well as other bridges in the vicinity or in similar of the hole at that pier (fig. 23). situations. Long-Term Channel-Bed Changes Shape of Scour Holes With the exception of structure A0767, all of the bridges A scour hole was present at every pier for which bathy- for which a Level II scour assessment was completed had a metry could be obtained and varied in depth relative to the lower channel-bed elevation during the bathymetric surveys upstream channel bed. A longitudinal profile was drawn than during the Level II survey in 2002, and all of the bridges upstream from the nose of each pier with a well-defined scour had a lower channel-bed elevation during the 2010 surveys hole (fig. 43), and the approximate frontal slope determined than when the bridge had been built. Researchers have stated for each hole (table 5). The frontal slope was not determined that water stage appears to be decreasing with time on the for the poorly defined scour hole at the right main channel Mississippi River for discharges less than flood stage (Brauer, pier (pier 6) of structure A4060 (fig. 23) or the main channel 2009; Huizinga, 2009). Huizinga (2009) stated that this likely pier at structure L0568, which had no scour hole specific to it is caused by a combination of channel deepening caused by (fig. 40). The approximate frontal slope of the scour holes at rock spur dikes in the channel and a decrease in the overall each of the remaining piers ranged from 1.77 to 2.49 (table 5). sediment load on the Missouri and Mississippi Rivers caused Richardson and Davis (2001) noted that the side slope of a by upstream reservoirs. A similar but more limited analysis scour hole in cohesionless sand could range from 1.0 to 1.8, to that in Huizinga (2009) was completed using data from depending on the composition of the bed material and its wet discharge measurements at the streamgage on the Missouri angle of repose. The slope values determined in the Kansas River at Kansas City, Missouri, where water-surface eleva- City area are somewhat greater than the range of values noted tions for a variety of discharge ranges from measurements at in Richardson and Davis (2001), except for structure A1800. the streamgage were plotted (fig. 44). Water-surface elevations As noted in the previous site-specific data, the movement were used instead of stage to remove the effects of a 10 ft of bed material manifested as dune features affected the bathy- datum shift in 1989. A decrease in the water-surface eleva- metric data at several of the bridges where a tilted transducer tions with time at the Kansas City streamgage was similar to head was used to obtain depth points at the pier after the gen- that observed on the Mississippi River at St. Louis, Missouri, eral channel bathymetric data had been collected. However, and Chester, Illinois (Huizinga, 2009), which implies a similar the shape of the scour holes at several of the bridges displayed decrease in the channel-bed elevations with time at the Kansas the effects of these dune movements as well. The scour hole City streamgage. The decrease with time appears to be greater upstream from structure K0456 has a squarish upstream edge, for lower discharges than for higher discharges (fig. 44). The which likely is the result of dunes moving into and around range of discharges observed during the bathymetric sur- the hole (figs. 13, 14). A similar squarish upstream edge was veys was 120,000 to 129,000 ft3/s, which corresponds to the observed at structure A4649 (figs. 18, 19) and structure A4757 125,000 ft3/s +/- 4 percent discharge range in figure 44. (figs. 39, 40). The scour hole at structure A1800 also was Dividing the total measured area by the measured top affected by dune movement, displayed by subtle “steps” and width from discharge measurements gives an average depth of waves present along the sides of the hole (fig. 9) and in the flow. Subtracting the average depth of flow from the water- longitudinal profile (fig. A43 ). Other profiles displayed similar, surface elevation value for a measurement provides an average but more subtle “steps” in the longitudinal profiles (figs. 40, channel-bed elevation. The average channel-bed elevation 43E, 43H). with time for all the measurements at the Kansas City, Mis- All of the bridges surveyed except structure A4060 souri, streamgage is shown in figure 45. With the exception had piers that were skewed to flow, resulting in asymmetric of several outliers that likely result from large floods (Huiz- scour holes at most of the bridges. The scour hole typically inga, 2009), the average channel-bed elevation has changed was deeper and longer on the side of the pier with impinging markedly with time. From the late 1920’s to 1940, the average flow, and some amount of deposition was on the leeward side channel-bed elevation appeared to be increasing with time, (figs. 10, 11, 14, 15, 19, 20, 30, 31, 35, 36, 40, 41). Bridges whereas the average channel-bed elevation has been decreas- with less than 5° of skew to the approach flow occasion- ing with time ever since (fig. 45). The general trend of the ally had asymmetric scour holes [structures K0456 and average channel-bed elevation with time is concave down- A0450 (figs. 13, 14)], and occasionally not [structure A5817 ward, which implies that the rate of change of the average (figs. 29, 30)]. Structures A4757 and L0568 had the largest channel-bed elevations is increasing with time, which likely skew (about 20°), which resulted in a large asymmetric scour is caused by sediment being trapped in upstream reservoirs. 56 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

A A' A A' B B' 725 705 705 A Structure A1800 B Structure K0456 C Structure A0450 720 700 700

715 695 695 Footing Caisson of Caisson 710 690 690 pier 7 of structure Seal K0456 705 course 685 685 Caisson

700 680 680

695 675 675 Drilled shaft 690 670 670 A A' A A' A A' 705 720 715 D Structure A4649 E Structure A4060, Pier 5 F Structure A5817 700 715 710

695 710 705

Footing Footing 690 705 700 Seal Seal course course 685 Caisson 700 695

680 695 690

675 690 685 Drilled Drilled shaft shaft 670 685 680 A A' A A' 7090100 6080 5040 30 20 10 0 710 700 G Structure A0767 H Structure A4757 705 695

Footing 700 690 EXPLANATION CHANNEL-BED ELEVATION, IN FEET ABOVE NORTH AMERICAN VERTICAL DATUM OF 1988 Channel bed from bathymetric surveys, 695 685 Seal in feet above North American course Footing Vertical Datum of 1988 690 680 Approximate frontal slope line Apparent frontal slope line when ignoring potential effects of dune 685 675 Seal movement course Pier substructural elements 680 670 Drilled shaft 675 665 7090100 6080 5040 30 20 10 0 7090100 6080 5040 30 20 10 0 DISTANCE UPSTREAM FROM PIER FACE, IN FEET Figure 43. Longitudinal profiles upstream from piers at the structures surveyed on the Missouri River at Kansas City, Figure 43. Longitudinal profiles upstream from piers at the structures surveyed on the Missouri River at Kansas City, Missouri. Missouri. Results of Bathymetric Surveys 57

740

735

730

725

720 AMERICAN VERTICAL DATUM OF 1988

715 WATER-SURFACE ELEVATION, IN FEET ABOVE NORTH

710 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

EXPLANATION Flood stage is 32 feet gage, or 738.66 feet above North American Vertical Datum of 1988 25,000 cubic feet per second +/- 5 percent 50,000 cubic feet per second +/- 5 percent 75,000 cubic feet per second +/- 5 percent 125,000 cubic feet per second +/- 4 percent 175,000 cubic feet per second +/- 4 percent Figure 44. Water-surface elevation for a given discharge range with time from measurements at the streamflow- Figure gaging 44. station Water-surface on the Missouri elevation River for a givenat Kansas discharge City, Missourirange with (station time from number measurements 06893000). made at the streamflow- gaging station on the Missouri River at Kansas City, Missouri (station number 06893000).

Since the time of the 1993 flood, the average channel-bed Flood durations on the Missouri River at Kansas City elevation has decreased by about 6 ft (fig. 45). This long-term generally are measured in weeks and months because of the change in channel-bed elevation is part of the reason that the large upstream drainage area. Therefore, contraction and pier foundations were exposed and undermined at the time of local scour effects at the bridges on the Missouri River in the the bathymetric surveys. Kansas City area appear to be well-established and appar- ently stable. Nevertheless, the Missouri River was in moderate Effects of Moderate Flooding During Surveys flood conditions during the week of surveying, which would have an effect on the local scour at the bridge sites. Huizinga Richardson and Davis (2001) separate long-term aggra- (2009) observed that the streamgages on the Mississippi River dation and degradation of a channel from the contraction and at St. Louis, Missouri, and Chester, Illinois, routinely experi- local scour that occur at a bridge site during floods. Contrac- ence channel degradation and infilling during the passage of a tion scour is the general change in the channel-bed elevation flood. During the 1993 flood, the measurement section at the across a bridge opening resulting from the passage of a flood St. Louis streamgage indicated as much as 24 ft of fluctuation through a constriction. Local scour is the localized erosion of in the channel thalweg during the flood, but the post-flood material caused by flow vortex action that forms near bridge channel bed configuration was similar to the pre-flood con- piers and abutments. Although all of the scour processes (long- figuration. The measurement section at the Chester streamgage term, contraction, and local scour) continually are at work, indicated steady degradation of more than 18 ft in the channel contraction and local scour generally are cyclic, resulting in a thalweg up to the peak of the flood, and steady aggradation decrease and increase of the channel-bed elevation during the after the peak, with a post-flood configuration within about passage of a flood. 8 ft of the pre-flood configuration. Therefore, the scour holes 58 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

720 Approximate trend of channel-bed elevation change 1928 to 1940

715

710

705

700 NORTH AMERICAN VERTICAL DATUM OF 1988 Approximate trend of AVERAGE CHANNEL-BED ELEVATION, IN FEET ABOVE channel-bed elevation change since 1993 flood

695 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

EXPLANATION Average channel-bed elevation before the 1993 flood, in feet above North American Vertical Datum of 1988 Average channel-bed elevation after the 1993 flood, in feet above North American Vertical Datum of 1988 Figure 45. Average channel-bed elevation with time from measurements at the streamflow-gaging station on the Figure Missouri 45. River Average at Kansas channel-bed City, Missouri elevation (station with time number from measurements 06893000). made at the streamflow-gaging station on the Missouri River at Kansas City, Missouri (station number 06893000).

observed at the bridges in the Kansas City area likely are tran- relevant error sources are taken into account (Kevin Oberg, sient, with some infilling upon recession of the flood condi- written commun., 2010). A representative example of the tions. If the bridges were to be surveyed at low-flow condi- spatial distribution of TPE typically observed in the survey tions, the scour holes likely would be smaller. data is shown in figure 46 for the bathymetric data at structure A1800. Error Estimation The largest TPE in the Kansas City surveys was about 2.8 ft; however, TPE values of this magnitude typically To estimate the potential errors in the surveys, the occurred near high-relief features, such as the front or side Combined Uncertainty Bathymetric Estimator (CUBE) of a pier footing or large submerged object (fig. 46). More method (Calder and Mayer, 2003) as implemented in the typically, TPE values were less than 1.5 ft, with larger values HYPACK®/HYSWEEP® software (HYPACK, Inc., 2009) occurring near moderate-relief features (banks, dune faces, was used to estimate total propagated errors (TPE) for the and scour holes; fig. 46). Occasionally, these larger TPE gridded surface of each survey area. The CUBE method values also occurred in the outermost beam portions of the effectively allows all random system component errors and multibeam swath in the overlap with an adjacent swath, typi- resolution effects to be combined and propagated through cally in the channel thalweg where substantial bed movement the survey processing steps, which provides a robust esti- would occur between survey passes (fig. 46). Substantial mate of the spatial distribution of possible error within the parts of the channel bed at all of the surveyed sites had TPE survey area (Kevin Oberg, U.S. Geological Survey, writ- values of 0.5 ft or less, and the tops of bridge substructural ten commun., 2010). Thus, the TPE of a point is a measure elements (pier footings and seal courses) typically had TPE of the accuracy to be expected for such a point, when all values of 0.2 ft or less (fig. 46). Results of Bathymetric Surveys 59 N 2.8 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 Total propagated Total of channel- error bed elevation, in feet EXPLANATION

94°38'50" March 15, 2010 734.83 feet above NAVD 88 734.83 feet above NAVD 129,000 cubic feet per second 0 500 100 150 25 200 250 FEET 50 75 METERS Survey Date Discharge (based on discharge at streamflow-gaging station at Kansas City) elevation water-surface Average

94°38'55"

94°39'

Pier 3 Pier 39°09'10"

94°39'05" Base from National Agricultural Imagery Program, 2007 Universal Transverse Mercator projection, Zone 15 Horizontal coordinate information referenced to the North American Datum of 1983 (NAD 83) Vertical coordinate information referenced to the North American Vertical Datum of 1988 (NAVD 88) 94°39'10"

Total propagated error of bathymetric data from the Missouri River channel in the vicinity of structure A1800 on Interstate 635 in Kansas City, Missouri. propagated error of bathymetric data from the Missouri River channel in vicinity structure A1800 on Interstate 635 Kansas City, Figure 46. Total

39°09'15" 39°09'20" Figure 46. Missouri. propagated error of bathymetric data from the Missouri River channel in vicinity structure A1800 on Interstate 635 Kansas City, Total 60 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010

Summary and the resultant scour holes displayed characteristics of deposition on the leeward side of the pier and greater depth on the side of the pier with impinging flow. Bathymetric surveys were conducted on the Missouri The channel bed at nearly all of the surveyed bridges River in the vicinity of nine bridges at seven highway cross- was lower than the channel bed at the time of Level II scour ings in Kansas City, Missouri, by the U.S. Geological Survey assessments in 2002 and was lower than the channel bed at in cooperation with the Missouri Department of Transporta- time of construction at all of the surveyed bridges. An analysis tion. A multibeam echo sounder mapping system was used to of measurement data from the streamgage on the Missouri obtain channel-bed elevations for areas ranging from 1,640 to River at Kansas City, Missouri, confirmed the lowering of the 1,800 feet long and extending from bank to bank in the main channel-bed elevations with time. channel of the Missouri River. These bathymetric scans will be The Missouri River was in moderate flood conditions at used by the Missouri Department of Transportation to assess the time of the surveys, and the size of the scour holes likely the condition of the bridges for stability and integrity with was affected by the conditions. It is likely that the scour holes respect to bridge scour. would be smaller during conditions of low flow. At nearly all of the surveyed bridges, large dune features were detected in the channel, as well as numerous smaller dunes and ripples. Several of the sites are on or near bends in the river, resulting in a deep channel thalweg on the outside References Cited of the bend at these sites. At structure A5817 on State High- way 269, evidence of bedrock exposure was in the channel Applanix Corporation, 2006, POS-MV™ V4 user guide, thalweg. Rev. 0: Richmond Hill, Ontario, Canada, PUBS–MAN– Bathymetric data were collected around every pier 000513, 369 p. that was in water, except those at the edge of water or in extremely shallow water, and one pier at structure A0767 on Applanix Corporation, 2009, POS-Pac™ MMS™ GNSS- Interstate 435, which was surrounded by a large debris raft. inertial tools user guide, Rev. 4: Richmond Hill, Ontario, A scour hole was present at every pier for which bathymetry Canada, PUBS–MAN–001768, 523 p. could be obtained. At bridges with caisson foundations, the surveyed channel bed at the bottom of the scour hole gener- Brauer, E.J., 2009, The limitations of using specific-gage ally was 40 to 50 feet above the bottom of the caisson at bed- analysis to analyze the effect of navigation structures on rock level, except at structure A4649 on U.S. Highway 169, flood heights in the Middle Mississippi River: Permanent where the bottom of the scour hole was about 5 feet above International Association of Navigation Congress, 2009 De bedrock. Paepe-Williams Award Contest, 18 p. At bridges with drilled shaft foundations, the upstream Calder, B.R., and Mayer, L.A., 2003, Automatic processing end of the seal course was exposed at all of the piers except of high-rate, high-density multi-beam echosounder data: the piers on the right (south) side of the channel at structure Geochemistry, Geophysics, Geosystems, v. 4, p. 1,048. A5817 on State Highway 269 and structure A0767 on Inter- state 435. Furthermore, the bottom of the scour hole generally Environmental Systems Research Institute, 2010, ArcGIS, was below the bottom of the seal course for piers with this accessed September 2010 at foundation type. The minimum elevation of the scour hole at http://www.esri.com/software/arcgis/ the main channel pier of structure A0767 on Interstate 435 was about 10 feet below the bottom of the seal course, and Hughes-Clarke, J.E., Mayer, L.A., and Wells, D.E., 1996, the sides of the drilled shafts were evident in a point cloud Shallow-water imaging multibeam sonars—A new tool for visualization of the data at that pier. Undermining of the seal investigating seafloor processes in the coastal zone and on course was evident as a sonic “shadow” in the point cloud the continental shelf: Marine Geophysical Researches, v. 18, visualization of several of the piers. The bottom of the scour p. 607–629. hole generally was 10 to 45 feet above bedrock, and drilled Huizinga, R.J., 2009, Examination of direct discharge mea- shafts generally penetrate 20 feet into bedrock. surement data and historic daily data for selected gages on The scour hole at a given pier varied in depth relative the Middle Mississippi River, 1861–2008: U.S. Geological to the upstream channel bed, depending on the presence and Survey Scientific Investigations Report 2009–5232, 60 p. proximity of other piers or structures upstream from the pier in question. At piers with well-defined scour holes, the frontal Huizinga, R.J., Elliott, C.M., and Jacobson, R.B., 2010, Bathy- slopes of the holes were greater than recommended values in metric and velocimetric survey and assessment of habitat the literature, except for structure A1800. The shape of the for pallid sturgeon on the Mississippi River in the vicinity holes appeared to be affected by the movement of dune fea- of the proposed Interstate 70 Bridge at St. Louis, Missouri: tures into and around the holes. All of the structures surveyed U.S. Geological Survey Scientific Investigations Report except structure A4060 had piers skewed to approach flow, 2010–5017, 28 p. References Cited 61

Huizinga, R.J., and Rydlund, P.H., Jr., 2004, Potential-scour U.S. Army Corps of Engineers, 2004a, Upper Mississippi assessments and estimates of scour depth using different River System flow frequency study, Appendix E: U.S. Army techniques at selected bridge sites in Missouri: U.S. Geologi- Corps of Engineers, Rock Island, Illinois, accessed Septem- cal Survey Scientific Investigations Report 2004–5213, 42 p. ber 2010 at http://www.mvr.usace.army.mil/pdw/pdf/flowfrequency/ HYPACK, Inc., 2009, HYPACK® Hydrographic survey soft- Documents/FinalReport/default.asp. ware user’s manual 1/09: Middletown, Conn., 1,394 p. kcICON Project, 2010, Interstate 29/35 Connections Project U.S. Army Corps of Engineers, 2004b, Engineering and Website, accessed July 26, 2010, at http://www.kcicon.org/. design—Hydrographic surveying: Washington D.C., U.S. Army Corps of Engineers, manual no. EM 1110–2–1003, Lagasse, P.F., Shall, J.D., Johnson, F., Richardson, E.V., 560 p. Richardson, J.R., and Chang, F., 1991, Stream stability at highway structures: U.S. Federal Highway Administration U.S. Geological Survey, 2003, User's manual for the National Publication FHWA–IP–90–014 Hydraulic Engineering Water Information System of the U.S. Geological Survey: Circular No. 20, 195 p. Automated Data Processing System (ADAPS): U.S. Geo- logical Survey Open-File Report 2003–123, 413 p., RESON, Inc., 2008, SeaBat™ 7125 high-resolution multi- accessed September 2010 at beam echosounder system operator’s manual, Version 6.01: http://pubs.usgs.gov/of/2003/ofr03123/. Goleta, Calif., 100 p. U.S. Geological Survey, 2010, National Water Informa- Richardson, E.V., and Davis, S.R., 2001, Evaluating scour at tion System: U.S. Geological Survey database, accessed bridges (4th ed.): U.S. Federal Highway Administration March 2010 at http://waterdata.usgs.gov/nwis/. Publication FHWA–NHI–01–001 Hydraulic Engineering Circular No. 18, 378 p. Wilson, G.L., and Richards, J.M., 2006, Procedural documen- Rydlund, P.H., Jr., 2009, Real-time river channel-bed moni- tation and accuracy assessment of bathymetric maps and toring at the Chariton and Mississippi Rivers in Missouri, area/capacity tables for small reservoirs: U.S. Geological 2007–09: U.S. Geological Survey Scientific Investigations Survey Scientific Investigations Report 2006–5208, 24 p. Report 2009–5254, 27 p. plus oversize figs.

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For more 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: http://mo.water.usgs.gov 62 Bathymetric Surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a Multibeam Echo Sounder, 2010 References Cited 63

Back cover. Point cloud visualization of the channel bed and left side of the main channel pier of structure A1800 on Interstate 635 over the Missouri River in Kansas City, Missouri. SIR 2010–5207 2010— Sounder, Echo a Multibeam using Missouri, City, Kansas in River Missouri the Crossing Bridges Highway at Surveys Huizinga —Bathymetric

Flow