SHEBOYGAN COUNTY, WISCONSIN, AND INCORPORATED AREAS
Community Community Name Number *ADELL, VILLAGE OF 550075 CASCADE, VILLAGE OF 550425 CEDAR GROVE, VILLAGE OF 550076 *ELKHART LAKE, VILLAGE OF 550564 GLENBEULAH, VILLAGE OF 550570 HOWARDS GROVE, VILLAGE OF 550608 KOHLER, VILLAGE OF 550426 OOSTBURG, VILLAGE OF 550427 PLYMOUTH, CITY OF 550428 RANDOM LAKE, VILLAGE OF 550429 SHEBOYGAN, CITY OF 550430 SHEBOYGAN FALLS, CITY OF 550431 SHEBOYGAN COUNTY UNINCORPORATED AREAS 550424 WALDO, VILLAGE OF 550432
* NO SPECIAL FLOOD HAZARD AREAS IDENTIFIED
APRIL 2, 2009
Federal Emergency Management Agency FLOOD INSURANCE STUDY NUMBER 55117CV000A
Sheboygan County, Wisconsin and Incorporated Areas
NOTICE TO FLOOD INSURANCE STUDY USERS
Communities participating in the National Flood Insurance Program have established repositories of flood hazard data for floodplain management and flood insurance purposes. This Flood Insurance Study (FIS) may not contain all data available within the repository. It is advisable to contact the community repository for any additional data.
The Federal Emergency Management Agency (FEMA) may revise and republish part or all of this Preliminary FIS report at any time. In addition, FEMA may revise part of this FIS report by the Letter of Map Revision (LOMR) process, which does not involve republication or redistribution of the FIS report. Therefore, users should consult community officials and check the Community Map Repository to obtain the most current FIS components. Selected Flood Insurance Rate Map panels for this community contain information that was previously shown separately on the corresponding Flood Boundary and Floodway Map panels (e.g., floodways and cross sections). In addition, former flood hazard zone designations have been changed as follows.
Old Zone(s) New Zone
A1 through A30 AE B X C X
Initial Countywide FIS Effective Date: April 2, 2009
TABLE OF CONTENTS
Page 1.0 INTRODUCTION 1
1.1 Purpose of Study 1
1.2 Authority and Acknowledgments 1
1.3 Coordination 4 2.0 AREA STUDIED 6
2.1 Scope of Study 6
2.2 Community Description 8
2.3 Principal Flood Problems 9
2.4 Flood Protection Measures 10 3.0 ENGINEERING METHODS 12
3.1 Hydrologic Analyses 12
3.2 Hydraulic Analyses 18
3.3 Vertical Datum 25 4.0 FLOODPLAIN MANAGEMENT APPLICATIONS 26
4.1 Floodplain Boundaries 26
4.2 Floodways 27 5.0 INSURANCE APPLICATIONS 43 6.0 FLOOD INSURANCE RATE MAP 44 7.0 OTHER STUDIES 44 8.0 LOCATION OF DATA 47 9.0 BIBLIOGRAPHY AND REFERENCES 47
i TABLE OF CONTENTS - continued
Page
FIGURES
FIGURE 1 – TRANSECT SCHEMATIC 15 FIGURE 2 – FLOODWAY SCHEMATIC 43
TABLES
TABLE 1 – INITIAL AND FINAL CCO MEETINGS 5 TABLE 2 – FLOODING SOURCES STUDIED BY DETAILED METHODS 6 TABLE 3 – SUMMARY OF DISCHARGES 15 TABLE 4 – TRANSECT DATA 21 TABLE 5 – MANNING'S "N" VALUES 24 TABLE 6 – FLOODWAY DATA 29 TABLE 7 – COMMUNITY MAP HISTORY 45
EXHIBITS
EXHIBIT 1 - Flood Profiles Batavia Creek Panels 01P - 02P Black River Panel 03P Black River Tributary No. 2 Panel 04P Fisher Creek Panels 05P - 06P Fisherman’s Creek Panels 07P - 08P LaBudde Creek Panel 09P Mullet River Panels 10P - 18P North Branch Milwaukee River Panels 19P - 23P Onion River Panels 24P - 28P Pigeon River Panels 29P - 33P Random Lake – Unnamed Tributary to Silver Creek Panel 34P Sheboygan River Panels 35P - 55P Silver Creek Panels 56P - 57P
EXHIBIT 2 - FLOOD INSURANCE RATE MAP INDEX FLOOD INSURANCE RATE MAP
ii FLOOD INSURANCE STUDY SHEBOYGAN COUNTY, WISCONSIN AND INCORPORATED AREAS
1.0 INTRODUCTION
1.1 Purpose of Study
This countywide Flood Insurance Study (FIS) revises and updates the FISs/Flood Insurance Rate Maps (FIRMs), Flood Hazard Boundary Maps (FHBMs) and Flood Boundary Floodway Maps (FBFMs) for the geographic area of Sheboygan County, Wisconsin, including the Cities of Plymouth, Sheboygan, and Sheboygan Falls, the Villages of Adell, Cascade, Cedar Grove, Elkhart Lake, Glenbeulah, Howards Grove, Kohler, Oostburg, Random Lake, and Waldo, and the unincorporated areas of Sheboygan County (hereinafter referred to collectively as Sheboygan County). Please note that the Villages of Adell and Elkhart Lake have no special flood hazard areas identified. Also note that the Villages of Adell, Cedar Grove, Elkhart Lake, Glenbuelah, Howards Grove, Oostburg and Waldo did not have previous FIS text.
This FIS aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This FIS has developed flood risk data for various areas of the county that will be used to establish actuarial flood insurance rates. This information will also be used by Sheboygan County to update existing floodplain regulations as part of the Regular Phase of the NFIP, and will also be used by local and regional planners to further promote sound land use and floodplain development. Minimum floodplain management requirements for participation in the NFIP are set forth in the Code of Federal Regulations at 44 CFR, 60.3.
In some states or communities, floodplain management criteria or regulations may exist that are more restrictive or comprehensive than the minimum Federal requirements. In such cases, the more restrictive criteria take precedence and the State (or other jurisdictional agency) will be able to explain them.
1.2 Authority and Acknowledgments
The sources of authority for this FIS are the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973.
Information on the authority and acknowledgment for each jurisdiction and all unincorporated areas included in this countywide FIS, as compiled from previously printed FIS reports, is shown below.
1 Plymouth, City of: The hydrologic and hydraulic analyses for the FIS dated January 5, 1983, were performed by the Federal Emergency Management Agency (FEMA). That work was completed in March 1982 (Reference 1).
Sheboygan, City of: For the original, September 15, 1976 FIS report and March 15, 1977, FIRM, the hydrologic and hydraulic analyses for the Sheboygan River and Lake Michigan were prepared by Owen Ayres and Associates for the Federal Insurance Administration (FIA), under Contract Number H-3600 (Reference 2).
For the December 2, 1988, FIS, the hydrologic and hydraulic analyses for Fisherman's Creek were prepared by the Wisconsin Department of Natural Resources (WDNR) (Reference 3).
For the April 2, 1991 FIS, the hydrologic and hydraulic analyses for the Sheboygan River were performed by the U.S. Army Corps of Engineers (USACE), Detroit District, for FEMA, under Inter-Agency Agreement No. EMW-87-E-2509, Project Order No. 10. That work was completed in December 1988 (Reference 4).
For the November 21, 2002 study, the hydrologic and hydraulic analyses for Lake Michigan were performed by the USACE, Detroit District, for FEMA, under Inter-Agency Agreement No. EMW-93-E-4115, Project Order No. 1. That work was completed in March 1994. Additional revisions to the hydrologic and hydraulic analyses of wave run- up were performed by Dewberry & Davis LLC. That work was completed September 1998 (Reference 5).
Planimetric base map files were derived by digitizing the City of Sheboygan, Wisconsin, FIRMs. These files were compiled at a scale of 1:6,000.
2 Sheboygan Falls, City of: For the FIS dated April 2, 1991, the hydrologic and hydraulic analyses for the Sheboygan River were performed by the COE, Detroit District for FEMA, under Inter-Agency Agreement No. EMW-87-E-2509, Project Order No. 10. That work was completed in December 1988 (Reference 6).
The hydrologic and hydraulic analyses for the Mullet River were taken from the published Flood Insurance Study for Sheboygan County, Wisconsin (Reference 7). The hydrologic and hydraulic analyses for the Onion River were taken from information developed in preparation of the FIS for Sheboygan County.
Cascade, Village of: The hydrologic and hydraulic analyses for the FIS dated April 15, 1981, were performed by Donohue and Associates, Inc., for the FIA, under Contract No. H-4726. That work was completed in November 1979 (Reference 8).
Kohler, Village of: The hydro1ogic and hydraulic analyses for the FIS dated April 2, 1991, were performed by the USACE, Detroit District for FEMA, under Inter-Agency Agreement No. EMW-87-E- 2509, Project Order No. 10. That work was completed in December 1988 (Reference 9).
Random Lake, Village of: The hydrologic and hydraulic analyses for the FIS dated October 1, 1980, were performed by Donohue & Associates, Inc., for the FIA, under Contract No. H-4726. That work was completed in May 1979 (Reference 10).
Sheboygan County For the January 17, 1978 FIS report and July (Unincorporated Areas) 17, 1978 FIRM, the hydrologic and hydraulic analyses were prepared by Owen Ayres and Associates, Inc. for the FIA, under Contract No. H-3805. That work was completed in March 1977 (Reference 11).
3 Sheboygan County For the December 16, 1988, FIS revision, the (Unincorporated Areas) hydrologic and hydraulic analyses were (continued) prepared by the WDNR. FEMA reviewed and accepted that data for purposes of that revision (Reference 7).
For the September 3, 1992, FIS revision, the hydrologic and hydraulic analyses were prepared by the USACE, Detroit District, for FEMA under Inter-Agency Agreement No. EMW-87-E-2509, Project Order No. 10. FEMA reviewed and accepted that data for purposes of that revision (Reference 12).
For the November 21, 2002, FIS revision, the hydrologic and hydraulic analyses were prepared by the USACEfor FEMA, under Inter-Agency Agreement No. EMW-93-E- 4115, Project Order No. 1. That work was completed in March 1994. Additional revisions to the hydrologic and hydraulic analyses of wave run-up were performed by Dewberry & Davis LLC. That work was completed in September 1998, and revised in accordance with WDNR review comments in February 2000 (Reference 13).
For this countywide FIS, redelineation of special flood hazard areas was performed by CDM Federal Programs Corporation, under contract HSFE05-05- D-0027/002. This work was completed September 18, 2006. The digital base mapping information was provided in digital format by Sheboygan County. Aerial photography is dated 2005 with a 1-meter resolution. Users of this FIS should be aware that minor adjustments may have been made to specific FIRM base map features.
The coordinate system used for the production of this FIRM is Universal Transverse Mercator (UTM), North American Datum of 1983 (NAD 83), GRS 80 spheroid. Differences in the datum and spheroid used in the production of FIRMs for adjacent counties may result in slight positional differences in map features at the county boundaries. These differences do not affect the accuracy of information shown on the FIRM.
1.3 Coordination
An initial Consultation Coordination Officer’s (CCO) meeting is held typically with representatives of FEMA, the communities and study contractors to explain
4 the nature and purpose of the FIS and to identify the streams to be studied by detailed methods. A final CCO meeting is held typically with representatives of FEMA, the communities, and the study contractors to review the results of the FIS.
The dates of the initial and final CCO meetings held for Sheboygan County and the incorporated communities within its boundaries are shown in Table 1, "Initial and Final CCO Meetings."
TABLE 1 – INITIAL AND FINAL CCO MEETINGS
Community Name Initial CCO Date Final CCO Date City of Plymouth * August 20, 1982 City of Sheboygan April 2, 1991 FIS October 9, 1986 May 2, 1990 November 21, 2002 FIS * July 20, 2000 City of Sheboygan Falls October 9, 1986 May 2, 1990 Village of Cascade March 14, 1978 November 18, 1980 Village of Kohler * May 2, 1990 Village of Random Lake March 15, 1978 May 1, 1980 Village of Waldo * * Sheboygan County, Unincorporated Areas January 17, 1978 FIS July 24, 1975 May 11, 1977 December 16, 1988 FIS * * September 3, 1992 FIS * * November 21, 2002 FIS * July 20, 2000 *Data not available.
The Villages of Oostburg and Waldo were converted by letter from the emergency phase of the NFIP to the regular phase August 3, 1998 and May 1, 1987, respectively. There were no previously prepared FIS reports issued for these communities.
For this countywide FIS, a pre-scoping report was prepared by Michael Baker Jr. dated March 2005. This report described work performed by WDNR to assemble the necessary information to perform the redelineation of special flood hazard areas based on improved topographic information. The initial coordination meeting was held July 28, 2005, and was attended by representatives of CDM, WDNR, FEMA and the community.
The results of the study were reviewed at the final CCO meeting held on April 10, 2007 and attended by representatives of CDM, WDNR, FEMA and the communities. All problems raised at that meeting have been addressed in this study.
5 2.0 AREA STUDIED
2.1 Scope of Study
This countywide FIS covers the geographic area of Sheboygan County, Wisconsin. The areas studied by detailed methods were selected with priority given to all known flood hazard areas and areas of projected development and proposed construction.
All or portions of the flooding sources listed in Table 2, "Flooding Sources Studied by Detailed Methods," were previously studied by detailed methods. The limits of detailed study are indicated on the Flood Profiles (Exhibit 1) and on the FIRM (Exhibit 2).
TABLE 2 – FLOODING SOURCES STUDIED BY DETAILED METHODS
Flooding Source Limits of Detailed Study
Batavia Creek From its confluence with the North Branch Milwaukee River to just downstream of State Route 28
Black River From its confluence with Lake Michigan to J.M. Kohler State Park
Black River Tributary No. 2 From its confluence with the Black River to just downstream County Truck Highway EE
Fisher Creek From the Village of Howard Grove’s corporate limits to just downstream County Truck Highway FF
Fisherman’s Creek From its confluence with the Black River to the City of Sheboygan’s corporate limits
LaBudde Creek From its confluence with the Mullet River to approximately 100 feet downstream of Highview Drive
Mullet River From its confluence with the Sheboygan River to the confluence with LaBudde Creek
North Branch Milwaukee River From the Sheboygan-Washington County line to Silver Creek Cascade Road
6 TABLE 2 – FLOODING SOURCES STUDIED BY DETAILED METHODS (continued)
Flooding Source Limits of Detailed Study
Onion River From the City of Sheboygan Fall’s corporate limits to State Route 32
Pigeon River From the confluence with Lake Michigan to the corporate limits of the Village of Howards Grove
Random Lake Within the corporate limits of the Village of Random Lake
Sheboygan River From the City of Sheboygan’s corporate limits to the Sheboygan-Manitowoc County line
Silver Creek From its confluence with the North Branch of the Milwaukee River to Creek Road
Unnamed Tributary to Silver Creek From Random Lake to the southern corporate limits of the Village of Random Lake
In the Village of Random Lake, the previously identified as Silver Creek has been renamed as Unnamed Tributary to Silver Creek, and in Sheboygan County, Unincorporated Areas, the stream previously identified as Black River Tributary No. 1 has been renamed as Fisherman’s Creek.
For the December 2, 1988 City of Sheboygan FIS, flood boundaries and a floodway were added along Fisherman's Creek in the southern portion of the city. Flood boundaries were revised and a floodway was added along the Pigeon River to match the FIS for the unincorporated areas of Sheboygan County, Wisconsin (Reference 7). Corporate limits were revised and the flooding information for the annexed areas was taken directly from the FIS for the unincorporated areas of Sheboygan County.
For the April 2, 1991, FIS, the Sheboygan River was restudied by detailed methods (Reference 4).
For the September 3, 1992, FIS, the Sheboygan River was restudied and the North Branch Milwaukee River was restudied downstream of Silver Creek Cascade Road (Reference 12).
7 All or portions of numerous flooding sources in the county were studied by approximate methods. Approximate analyses were used to study those areas having a low development potential or minimal flood hazards. The scope and methods of study were proposed to, and agreed upon by, FEMA and Sheboygan County.
All or portions of Black River Tributary No. 2 and Fisherman's Creek were studied by approximate methods.
A wetland area on the east side of the Village of Cascade, located between State Highway 28 and County Highway NN, was studied using approximate methods.
A wetland area in the southwest corner of the Village of Random Lake, west of County Highway K, and a portion of Silver Creek that passes through the northwest corner of the community were studied by approximate methods.
All or portions of the North Branch Milwaukee River, Silver Creek, Mink Creek, Melius Creek, Chambers Creek, Barr Creek, the Black River, the Sheboygan River, the Onion River, the Mullet River, Jackson Creek, LaBudde Creek, Meeme Creek, Sevenmile Creek, Fisher Greek, Bennutt Creek, the Pigeon River, and several unnamed tributaries of the aforementioned streams were studied by approximate methods.
For this countywide study, the flood boundaries of all flooding sources previously studied by detailed or approximate methods were redelineated based on updated topographic information. Several areas of approximate flooding were extended in order to match the approximate flooding across community corporate limits within Sheboygan County and across the county boundary from contiguous counties.
2.2 Community Description
Sheboygan County is located in eastern Wisconsin, along the Lake Michigan shore, entirely within the Lake Michigan drainage basin. About three-quarters of the county is located in the Sheboygan River watershed; a small portion in the northeast is located in the Manitowoc River watershed; while the remainder, in the southwest, is located in the Milwaukee River watershed. The Sheboygan River enters the county from the north and flows south by southeast before emptying into Lake Michigan in the City of Sheboygan. Its many tributaries flow in broad lowland dendritic patterns. The North Branch Milwaukee River flows through the western portion of the county, with fewer tributaries than the Sheboygan. Also located in the western portion of the county are numerous lakes, marshes and wooded areas, especially near the border with Fond du Lac County. Sheboygan County is located in the Eastern Ridges and Lowlands geographical province of Wisconsin, in the Central Lake Michigan Coastal and Southeast Glacial Plains ecological landscapes, where the topography is flat with few, low-
8 lying features. The population of Sheboygan County was 112,646 in 2000, 103,817 in 1990 and 100,935 in 1980 (Reference 14).
The topography of the county is marked by the Kettle Moraine, which traverses the county in a northeast to southwest direction. The landscape of the area has been influenced by the effects of glaciers that covered most of Wisconsin from approximately 10,000 to 11,000 years ago.
The major soil associations are the Aocheim-Theresa and Casco-Fox-Redman in the western part of the county. The east has clayey or loamy soils, such as those of the Kewaunee-Waynor-Manawa Association. Where the county borders Lake Michigan, the soil is composed of the loamy over clayey and sandy soils of the Hebron-Mosel-Oakville Association.
The climate is classified as continental, with cold, snowy winters and warm, humid summers. All of the seasons are tempered by the presence of Lake Michigan. The temperature for summer is influenced by a cooling effect from the lake, while the lake has a warming effect in winter. The average temperatures for January and July are 22 degrees Fahrenheit (°F) and 73°F, respectively (Reference 15). The average annual precipitation is 21 inches.
The Sheboygan River has a drainage area of approximately 432 square miles, with an average gradient of 4.6 feet per mile at the U.S. Geological Survey (USGS) gage, which is located on the left bank and 400 feet upstream of U.S. Route 141 (Reference 16). The river was once a source of power for operating feed, saw, and wool mills along with tanning and small hydroelectric plants. Currently, the river is principally utilized for recreation.
Other streams in the county include the North Branch Milwaukee River and its tributaries, which drain the southwestern portion of the county. The Black River flows into Lake Michigan near the southern edge of the county. The Onion River flows into the Sheboygan River near Sheboygan Falls, while draining a good part of the south-central portion of the county. The Mullet River has an average gradient of 9.9 feet per mile and LaBudde Creek flows into the Mullet River. The Pigeon River drains the northeastern part of the county, and flows into Lake Michigan near the north edge of the City of Sheboygan.
Floodplains include residential, commercial, agricultural, and industrial developments.
2.3 Principal Flood Problems
Sheboygan County is most susceptible to flooding in spring due to a combination of rapid snowmelt, spring rains, and frozen ground. Ice and debris may jam at bridge constrictions and cause much higher river stages than would normally be expected during a flood.
9
The largest and most disastrous flood in the area occurred in June 1905, on the Sheboygan and Mullet Rivers. Other large floods have occurred in 1883, 1920, 1926, 1960, 1966, 1975, 1978 and 1979. Other than these floods, no record of recent floods of any substantial magnitude exists. The maximum observed discharge on the Sheboygan River was 7,140 cubic feet per second (cfs), which occurred on March 2, 1920. According to current data, this would be slightly greater than a 10-percent annual chance flood.
The greatest floods recorded at the Sheboygan River gage at Sheboygan during the period of record (1917-23, 1951-present) occurred on March 22, 1975 – 7,680 cfs (estimated as a 20-year frequency flood); May 13, 1978 – 7,410 cfs; March 26, 1920 – 7,140 cfs; and March 31, 1979 – 6,460 cfs (approximately a 10-year frequency flood) (Reference 16). No documented data is available for the frequency of past flooding on the Mullet River, since no gages are located in the study area.
The elevation of Lake Michigan during floods is an important factor. Wind setup and wave action can cause damage to shoreline property, especially during periods of high lake stage. Shoreline erosion is a problem in the county, as evidenced by the sloughing of the shoreline in some areas. This FIS does not cover erosion. Section 3.2 discusses wave runup in more detail.
There is no record of a severe flood occurring on the North Branch Milwaukee River in the Village of Cascade; however, moderate flooding does occur approximately once every five years. The most recent flood was in the spring of 1974, when heavy rain and a dam failure on the south end of Mill Pond caused flooding in the village park and a low lying area near the Francis Avenue Bridge. No records of monetary damage to property exist and the water subsided in two days. The approximate study area, located east of County Highway NN, is a low region which has never undergone severe flooding. This area occasionally becomes flooded due to heavy rains, and no record of monetary damage can be recalled by village residents.
Local residents have indicated that Random Lake may rise a few inches after a heavy rain, but this condition subsides within a few hours. Inundation on lake front properties has not been known to extend horizontally more than 5 to 10 feet. A low region located west of County Highway K, studied by approximate methods, may become saturated during a heavy rain, but will not remain covered by standing water. County Highway 11, located on the northern perimeter of the area, requires seasonal repairs due to the unstable subsoils.
2.4 Flood Protection Measures
Franklin Dam, which was located on the Sheboygan River within the Village of Elkhart Lake, was originally a timber and earth dam built in 1851 to service a
10 gristmill operation. The original dam failed and was replaced by a concrete dam in the 1920s. The dam was evaluated by the USACE, and was determined to be undersized and unsafe in 1988. It was abandoned and declared unsafe by WDNR in 2000 (Reference 17). See section 3.2 for more information.
In many areas of the City of Sheboygan along Lake Michigan, riprap has been placed to reduce wave erosion. No other flood control structures, either along the lake shore or on the rivers, are known to exist within the city.
Levees exist in the City of Sheboygan Falls that provide the community with some degree of protection against flooding. However, it has been ascertained that the levees do not protect the community from major events such as the 1-percent annual chance flood. The criteria used to evaluate protection against the 1-percent annual chance flood are: 1) adequate design, including freeboard, 2) structural stability, and 3) proper operation and maintenance. Levees that do not protect against the 1-percent annual chance flood are not considered in the hydraulic analysis of the 1-percent annual chance floodplain.
A dam that provides some flood protection exists on the Sheboygan River just upstream of Monroe Street in the City of Sheboygan Falls. However, the dam may not provide protection against major events such at the 1-percent annual chance flood.
A small earthen dike exists along the west side of the North Branch Milwaukee River immediately downstream of the Francis Avenue Bridge in the Village of Cascade. This dike would assist in channelizing the flow during low frequency flood events; however, the dike would provide little or no flood protection during major flood events.
A small stop log dam is located at the south end of Mill Pond. No stop logs are installed at the structure. Mill Pond is principally used for recreation and little flood protection would be provided even if stop logs were installed.
Portions of the Village of Cascade along the North Branch Milwaukee River are zoned as conservancy in the village's zoning ordinance.
A dam at the outlet of Random Lake serves a twofold purpose. Its primary function is to keep unwanted fish out of the lake, which has been poisoned and restocked with game fish. It is also used to maintain the elevation of the lake and could be used to control the lake level in the event of high water problems. Random Lake is currently restricting flood plain development through zoning ordinances.
11 3.0 ENGINEERING METHODS
For the flooding sources studied in detail in the county, standard hydrologic and hydraulic study methods were used to determine the flood hazard data required for this FIS. Flood events of a magnitude which are expected to be equaled or exceeded once on the average during any 10-, 2-, 1-, or 0.2-percent annual chance flood event (recurrence interval) have been selected as having special significance for floodplain management and for flood insurance rates. These events, commonly termed the 10-, 50-, 100-, and 500-year floods, have a 10-, 2-, 1-, and 0.2-percent chance, respectively, of being equaled or exceeded during any year. Although the recurrence interval represents the long term average period between floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. The risk of experiencing a rare flood increases when periods greater than 1 year are considered. For example, the risk of having a flood which equals or exceeds the 1-percent annual chance flood in any 50-year period is approximately 40 percent (4 in 10), and, for any 90-year period, the risk increases to approximately 60 percent (6 in 10). The analyses reported herein reflect flooding potentials based on conditions existing in the county at the time of completion of this FIS. Maps and flood elevations will be amended periodically to reflect future changes.
3.1 Hydrologic Analyses
Hydrologic analyses were carried out to establish the peak discharge-frequency relationships for the flooding sources studied in detail affecting the county.
Pre-Countywide Analyses:
Batavia Creek discharges were computed by the U.S. Soil Conservation Service (SCS) method and checked with Conger's method (References 18 and 19). Soils data were obtained from an SCS publication, while rainfall data were obtained from U.S. Weather Bureau Technical Paper No. 40 (References 20 and 21).
The discharges for the Black River and Black River Tributary No. 2 were computed utilizing the SCS method and the USACE Unit Hydrograph method and checked with Conger's method (References 18 and 22).
Fisher Creek discharges were computed using the SCS and Conger's methods (References 18 and 19).
A hydrologic study was completed by the WDNR for the Fisherman's Creek watershed. This study determined the 1-percent annual chance flood peak discharge using the SCS rainfall runoff computer model in TR-55 and the 0.2- percent annual chance peak discharge using the HEC-1 computer model (References 23 and 24).
LaBudde Creek discharges were computed by a combination of the SCS method, a comparison to the Mullet River, and by Conger's method (References 18 and
12 19). The resulting discharges used were based on a weighted average of the two methods.
Discharges for Mullet River were taken from the USACE "Flood Plain Information" report (Reference 25) and are based on regional frequency analysis utilizing records of gauging stations on streams with similar hydrologic, topographic and physical characteristics. Determinations are in accordance with base method and procedures recommended by the U.S. Water Resources Council in A Uniform Technique for Determining Flood Flow Frequencies (Reference 26).
The Sheboygan County Floodplain Information Report is also available for part of the Mullet River (Reference 27). The 1-percent annual chance flood discharges shown in the report were extended to include other locations by a drainage area- discharge curve. The remaining discharges were computed by SCS methods and procedures similar to those for the Sheboygan River.
Discharges for the 10-, 2-, and 1-percent annual chance floods for the North Branch Milwaukee River used for the Village of Cascade were obtained from the Southeastern Wisconsin Regional Planning Commission (SEWRPC) report, entitled A Comprehensive Plan for the Milwaukee River Watershed (Reference 28). Discharges were computed using SCS TR-20 computer program (Reference 29). The discharges were based on 1990 planned land uses, which for the Cascade area would not be significantly different than existing land uses. These flows were verified with equations developed by D.H. Conger (Reference 19). The flows were plotted on log probability paper, and the 0.2-percent annual chance flood discharge was determined by a straight-line projection.
For the Sheboygan County September 3, 1992 revision, discharges for the North Branch Milwaukee River were determined utilizing a rainfall-runoff model developed for the Milwaukee River and the North Branch Milwaukee River. The WDNR developed this model using the HEC-1 computer model (Reference 30). This model was utilized to establish discharges at selected sites for the 10-, 2-, l-, and 0.2-percent annual chance flood events. The 24-hour rainfall events used for these frequencies were 3.9, 5.0, 5.4, and 6.2 inches, respectively.
The Onion River discharges were computed by a combination of the following methods: (1) drainage area comparison to the Mullet River; (2) unit hydrograph transfer from the Sheboygan River, using the Sheboygan Floodplain Information report; and Conger's method (References 27 and 19). A weighted curve that was developed based on the three methods was used.
Discharges for the Pigeon River were computed using a combination of a drainage area comparison to the Sheboygan River, and transfer of the unit hydrograph from the Sheboygan River (Reference 31). The 1-percent annual chance flood peak discharge was determined using the SCS rainfall-runoff
13 computer model, and the 0.2-percent annual chance flood peak discharge was determined using the HEC-1 computer model (References 23 and 32).
Peak discharges for Random Lake and Unnamed Tributary to Silver Creek were determined by methods described in a Milwaukee River watershed report prepared by the SEWRPC (Reference 28). The hydrologic analysis for Random Lake and Unnamed Tributary to Silver Creek to establish the peak discharge relationship for floods of the 10-, 2-, and 1-percent annual chance flood event was made utilizing the SCS hydrology computer program TR-20 (Reference 29). The principal factors considered in this method are soil types, land uses, slope of terrain, general channel slope and shape, and rainfall distribution. The 0.2-percent annual chance flood discharges were calculated using a straight-line projection on log-probability paper. The discharges in the report are based on 1990 land uses, which, for the Random Lake area, would not be significantly different than existing land uses.
Discharge-frequency relationships based on peak annual flows for the Sheboygan River were obtained from the USGS gage located just upstream of U.S. Route 141 and the USGS gage located on the Sheboygan River at City of Sheboygan. A flood flow frequency analysis was performed using Weibull plotting positions and the log-Pearson Type III distribution (Reference 33). A generalized skew of 0.2 and a mean square error of 0.14 were used, based upon State requirements. The flows were then adjusted from the USGS gage site to other locations on the Sheboygan River using a drainage area ratio method (Reference 31).
Discharges for Silver Creek were obtained from the published report prepared by SEWRPC, entitled A Comprehensive Plan for the Milwaukee River Watershed (Reference 28).
Deepwater wave heights and their associated wave periods can be found in the USACE report entitled, Hindcast Wave Information /for the Great Lakes: Lake Michigan (Reference 34). The wave run-up component was determined using the procedures developed in the FEMA report entitled, Guidelines and Specifications for Wave Elevation Determination and V-Zone Mapping–Great Lakes (Reference 35). Typical Relationships between wind setup and wave run-up are shown in Figure 1.
14 FIGURE 1 – TRANSECT SCHEMATIC
Figure 1 also depicts the addition of run-up to the storm-water surface caused by wind-generated waves. This simultaneous occurrence of storm-water lake levels and wind-wave actions was used for all run-up computations. It should be noted that the floodplain delineation for Lake Michigan does include flooding resulting from wave run-up.
A summary of the drainage area-peak discharge relationships for all the streams studied by detailed methods is shown in Table 3, “Summary of Discharges.”
TABLE 3 – SUMMARY OF DISCHARGES PEAK DISCHARGES (cfs) DRAINAGE 10-PERCENT 2-PERCENT 1-PERCENT 0.2-PERCENT FLOODING SOURCE AREA ANNUAL ANNUAL ANNUAL ANNUAL
AND LOCATION (sq. miles) CHANCE CHANCE CHANCE CHANCE
BATAVIA CREEK At mouth 6.8 560 900 1,070 1,500 At Batavia 4.5 435 700 830 1,170
BLACK RIVER At mouth 18.3 1,300 2,100 2,500 3,500 Above confluence of Black River Tributary No. 2 14.7 1,000 1,730 2,100 3,100
BLACK RIVER TRIBUTARY NO. 2 At mouth 1.8 350 700 900 1,460
15 TABLE 3 – SUMMARY OF DISCHARGES (continued) PEAK DISCHARGES (cfs) DRAINAGE 10-PERCENT 2-PERCENT 1-PERCENT 0.2-PERCENT FLOODING SOURCE AREA ANNUAL ANNUAL ANNUAL ANNUAL
AND LOCATION (sq. miles) CHANCE CHANCE CHANCE CHANCE
FISHER CREEK At mouth 10.6 970 1,600 1,900 2,700 At County Trunk Highway FF 2.6 420 690 820 1,160 At County Trunk Highway MM 1.3 270 450 530 750
FISHERMAN’S CREEK Just upstream of Lakeside Drive 3.0 N/A N/A 1,900 2,880 Just upstream of South 12th Street 2.7 N/A N/A 1,700 2,560 At mouth 2.7 N/A N/A 1,900 2,720
LABUDDE CREEK At mouth 10.2 750 1,200 1,450 2,050
MULLET RIVER At mouth 85.0 2,030 3,250 3,800 5,300 Above Mill Dam at Plymouth 58.6 1,700 2,700 3,200 4,500 Below confluence of LaBudde Creek 45.0 1,575 2,525 3,050 4,310 Above confluence of LaBudde Creek 34.8 1,515 2,425 2,930 4,140
NORTH BRANCH MILWAUKEE RIVER Approximately 1.3 miles downstream of State 92.3 3,580 4,865 5,465 6,535 Route 144 Just upstream of confluence of Silver Creek 72.4 2,630 3,635 3,995 4,850 Just upstream of confluence of Mink Creek 52.0 1,540 2,180 2,445 2,950 Just upstream of confluence of Batavia Creek 40.3 1,125 1,735 1,950 2,475 Approximately 3,200 feet downstream of Milwaukee Avenue 8.6 500 840 1,000 1,500
16 TABLE 3 – SUMMARY OF DISCHARGES (continued) PEAK DISCHARGES (cfs) DRAINAGE 10-PERCENT 2-PERCENT 1-PERCENT 0.2-PERCENT FLOODING SOURCE AREA ANNUAL ANNUAL ANNUAL ANNUAL
AND LOCATION (sq. miles) CHANCE CHANCE CHANCE CHANCE
ONION RIVER Just downstream of Buffalo Street 105.0 N/A N/A 6,000 N/A At Sheboygan Falls corporate limits 98.1 2,900 4,900 6,000 8,800 Upstream of confluence of Unnamed Tributary 83.6 2,700 4,600 5,600 8,100 At State Route 32 77.6 2,600 4,450 5,400 7,900
PIGEON RIVER At mouth 80.3 2,400 4,250 5,150 7,700 Above confluence of Unnamed Tributary 69.4 2,200 3,800 4,650 6,850 Below confluence of Fisher Creek 61.3 2,000 3,500 4,200 6,200
RANDOM LAKE Outlet at State Highway 144 3.7 85 110 120 140
SHEBOYGAN RIVER At U.S. Route 141 418.0 6,420 9,100 10,200 12,500 At Interstate Route 141 417.0 6,410 9,085 10,185 12,480 At Interstate Route 43 417.0 6,410 9,085 10,185 12,480 About 1,500 feet downstream of confluence of 405.0 6,300 8,930 10,010 12,265 Onion River Just upstream of confluence of Onion River 299.5 4,615 6,650 7,455 9,000 Just upstream of confluence of Mullet River 211.9 3,295 4,765 5,350 6,500 At County Highway JJ 200.0 2,855 4,065 4,585 5,560 At County Highway MM 185.0 2,440 3,465 3,875 4,730 Approximately 2,000 feet upstream of State Route 57 177.0 1,975 2,765 3,070 3,750
SILVER CREEK Just upstream of confluence of North Branch Milwaukee River 19.8 1,570 2,190 2,430 3,100 At Town Road 17.4 1,210 1,710 1,910 2,450
UNNAMED TRIBUTARY TO SILVER CREEK At Private Drive 1.18 175 230 255 310
17 This County-Wide Analysis:
There were no revisions made to the hydrologic information used to establish previously published discharges.
3.2 Hydraulic Analyses
Analyses of the hydraulic characteristics of flooding from the source studied were carried out to provide estimates of the elevations of floods of the selected recurrence intervals. Users should be aware that flood elevations shown on the FIRM represent rounded whole-foot elevations and may not exactly reflect the elevations shown on the Flood Profiles or in the Floodway Data tables in the FIS report. Flood elevations shown on the FIRM are primarily intended for flood insurance rating purposes. For construction and/or floodplain management purposes, users are cautioned to use the flood elevation data presented in this FIS report in conjunction with the data shown on the FIRM.
Cross sections were determined from topographic maps and field surveys. All bridges, dams, and culverts were field surveyed to obtain elevation data and structural geometry. All topographic mapping used to determine cross section is referenced in Section 4.1.
Locations of selected cross sections used in the hydraulic analyses are shown on the Flood Profiles (Exhibit 1). For stream segments for which a floodway was computed (Section 4.2), selected cross section locations are also shown on the FIRM (Exhibit 2).
Each incorporated community within, and the unincorporated areas of, Sheboygan County, with the exceptions of the Villages of Adell, Cedar Grove, Elkhart Lake, Glenbuelah, Howards Grove, Oostburg and Waldo has a previously printed FIS report. The hydraulic analyses described in those reports have been compiled and are summarized below.
Pre-Countywide Analyses:
For the 1978 unincorporated areas FIS, 223 field-measured cross sections were used. In addition, the USACE and the WDNR provided cross sections on the Sheboygan and Mullet Rivers. The WDNR and the Sheboygan County Highway Department provided bridge plans for most of the bridges added or rebuilt since the Floodplain Information Report was completed (Reference 37, 38, 39, and 40). For the Onion and Pigeon Rivers, the county provided maps at a scale of 1:2,400, with a contour interval of 2 feet, which were utilized for the overbank portions of the cross sections in these areas (Reference 41).
Stream mileages for the Fisherman’s Creek, Pigeon River and the Sheboygan River, were compared to and agreed with the FISs for the City of Sheboygan and the
18 unincorporated areas of Manitowoc County (References 2 and 42). Stream miles used in the Floodplain Information Report were revised due to updated and enlarged maps (References 43, 44 and 45). All stream distances were measured utilizing standards set by U.S. Water Resources Council Bulletin No. 14 (Reference 46).
All cross sections for the North Branch Milwaukee River were obtained by a field survey. Bridges and other hydraulically significant structures were field surveyed to obtain elevations and structural geometry.
In the 1988 unincorporated areas revision, cross-section data for streams were taken every 200 to 300 feet, and were interpolated using orthophoto maps at a scale of 1:1,200, with a contour interval of 2 feet (References 43 and 47).
Additional cross-section data for the Sheboygan and North Branch Milwaukee Rivers were provided by the WDNR. Sections along the Sheboygan River near the Villages of Johnsonville and Franklin, Wisconsin, were obtained by field survey. The Wisconsin Department of Transportation (WDOT) and the Sheboygan County Highway Department provided bridge plans for most of the bridges added or rebuilt since 1977.
Water surface elevations for reaches studied in detail along Batavia Creek, Black River, Fisher Creek, Fisherman’s Creek, LaBudde Creek, Mullet River, North Branch Milwaukee River, Onion River, Pigeon River, Sheboygan River and Silver Creek were computed using a USACE HEC-2 step back-water program (Reference 36).
Water surface elevations for Fisherman's Creek were also computed using a USACE HEC-2 step-backwater computer program (Reference 48). Starting water-surface elevations were obtained from the 10-percent annual chance flood elevation on the Black River at the confluence of Fisherman's Creek (Reference 3).
For the Pigeon River, water-surface elevations of floods of the selected recurrence intervals were computed using another variation of the COE HEC-2 step- backwater computer program (Reference 49). Starting water-surface elevations were determined by the slope/area method.
Analyses for Random Lake and the Unnamed Tributary to Silver Creek are described in the Milwaukee River watershed study prepared by SEWRPC (Reference 28). Starting water-surface elevations for Unnamed Tributary to Silver Creek were based on the elevations of Random Lake. Water-surface elevations on the Unnamed Tributary to Silver Creek of floods of the selected recurrence intervals were computed through the use of the USACE computer program 22-J2-L212, Backwater-Any Cross Section (Reference 50). The effects of various hydraulic structures and stream conditions were considered in the computations. Elevations for Random Lake were based on the calculated stage-discharge relationship for the
19 outlet structure of the lake. For the 0.2–percent annual chance flood event, the backwater from the lake extends upstream along the Unnamed Tributary to Silver Creek to the corporate limit. Flood profiles were drawn showing computed water- surface elevations to an accuracy of 0.5 foot for floods of the selected recurrence intervals. The analyses do not include contributions from wave crest height and wave runup. Nonetheless, the additional hazard due to wave action effect should be considered in planning future development.
The starting water-surface elevation for the Sheboygan River was obtained from the long-term average lake level of Lake Michigan at Sheboygan (Reference 51). Backwater computations for conditions upstream of dams were checked using rating curves or hand computations. The starting water-surface elevation for the North Branch Milwaukee River was determined using the slope-area method.
Flood profiles for the Mullet River were compared to the published Floodplain Information report (Reference 27). The water-surface profiles were generally within 1.0 foot of the published report but, in specific areas, varied by as much as 4.0 feet. This was due to the updated hydraulic techniques and the addition of several new bridges along the river.
The 1-percent annual chance flood profile computed for the North Branch Milwaukee River was compared to the report prepared by SEWRPC, A Comprehensive Plan for the Milwaukee River Watershed, (Reference 28). Due to new bridges and updated hydraulic techniques, the elevations varied by as much as 4.0 feet near the upstream end of the study area.
For streams studied by approximate methods in the 1978 studies, elevations were delineated using flood-prone soil maps contained within a SCS Interim Soil Survey Report for Sheboygan County (Reference 15).
For areas studied using approximate methods along the southern corporate limit of the Village of Random Lake, the flooding limits from a 1-percent annual chance, 24-hour storm were calculated. The limits of flooding were found to compare quite closely with the limits of swamp area shown on USGS maps (Reference 52) and SCS Soil Survey Maps (Reference 53). For the portion of Silver Creek in the northwest corner of the community, the approximate 1-percent annual chance flooding limits were determined from a FHBM (Reference 53) and the SEWRPC report (Reference 28).
A dam breach analysis for the Franklin Dam on the Sheboygan River was performed by the COE as directed by the WDNR (Reference 55). The WDNR dam safety and floodplain zoning programs required modifications to both the limits of flooding and flood elevations to account for the possible failure of the dams during a 1-percent annual chance flood. The dam was completely removed by WDNR in 2001.
20 Users of the FIRM should be aware that coastal flood elevations are provided in the Transect Descriptions and Data table in this report. If the elevation on the FIRM is higher than the elevation shown in this table, a wave height, wave runup and/or wave setup component likely exists, in which case, the higher elevation should be used for construction and/or floodplain management purposes. Coastal analyses for Lake Michigan were conducted to estimate the wave runup above the 1-percent annual chance flood elevation for the study area from north of the county boundary at Pebble Beach Road to the northernmost county boundary. The wave runup components and maximum wave runup elevations for individual sites located along the Sheboygan County shoreline were determined using methodologies established by the USACE in conjunction with the aforementioned FEMA report (Reference 35). In June 1993, field surveys were conducted to determine profile ground elevations along the transects. Wave runup was computed along transects located perpendicular to the shoreline, with consideration given to the physical and cultural characteristics of the land.
Along each transect, the maximum wave runup elevations were computed considering the combined effects of changes in ground elevation, vegetation, and physical features. Between transects, elevations were interpolated using topographic maps, land-use and land cover data, and engineering judgment to determine the aerial extent of flooding. The results of this analysis are summarized in Table 4, "Transect Data". Revisions to the maximum wave runup elevations north of the City of Sheboygan along the Lake Michigan shoreline were extrapolated from the revised coastal analyses for Transect 3 in the City of Sheboygan.
TABLE 4 – TRANSECT DATA ELEVATION (feet NAVD)* 1-PERCENT 1-PERCENT 0.2-PERCENT ANNUAL COMPUTED WAVE ANNUAL
TRANSECT LOCATION CHANCE RUNUP (RUNUP) CHANCE
1 Along Lake Michigan 584.3 4.6 588.9 585.2 shoreline in the areas of unincorporated Sheboygan County from south county limits with Ozaukee County at Pebble Beach Road along Surfside Drive.
2 Along Lake Michigan 584.3 2.3 586.6 585.2 shoreline in unincorporated areas Sheboygan County, from a stream mouth located about 2, 200 feet north of Pebble Beach Road to Windmill Beach Road.
21 TABLE 4 – TRANSECT DATA (continued) ELEVATION (feet NAVD)* 1-PERCENT 1-PERCENT 0.2-PERCENT ANNUAL COMPUTED WAVE ANNUAL
TRANSECT LOCATION CHANCE RUNUP (RUNUP) CHANCE
3 Along Lake Michigan 584.3 3.9 588.2 585.2 shoreline in the unincorporated areas of Sheboygan County, from Windmill Beach Road to about 2,350 feet south of Dewitt Road
4 Along lake Michigan 584.3 2.7 587.0 585.2 shoreline in the unincorporated areas of Sheboygan County, from about 2, 350 feet south of Dewitt Road to about 500 feet north of Stokdyke Road along Pine Beach North
5 Along Lake Michigan 584.3 4.4 588.7 585.2 shoreline in the unincorporated areas of Sheboygan County, from about 500 feet north of Stokdyke-Inglese Road along North Pine Beach to about 1, 800 feet north of Wilson- Lima Road
6 Along Lake Michigan 584.3 5.7 590.0 585.2 shoreline in the unincorporated areas of Sheboygan County, from about 1,800 feet north of Wilson-Lima Road to about 950 feet north of Old Park Road
7 Along Lake Michigan 584.3 3.8 588.1 585.2 shoreline in the unincorporated areas of Sheboygan County, from about 950 feet north of Old Park road to county limits with south limits of the City of Sheboygan
22 TABLE 4 – TRANSECT DATA (continued) ELEVATION (feet NAVD)* 1-PERCENT 1-PERCENT 0.2-PERCENT ANNUAL COMPUTED WAVE ANNUAL
TRANSECT LOCATION CHANCE RUNUP (RUNUP) CHANCE
8 Along Lake Michigan 584.3 2.7 587.0 585.2 shoreline in the City of Sheboygan, from just north of Highland Terrace to just south of Evergreen Avenue.
9 Along Lake Michigan 584.3 6.1 590.4 585.2 shoreline in the City of Sheboygan, from the north jetty at Deland Park to just north of Highland Terrace.
10 Along Lake Michigan 584.3 6.1 590.4 585.2 shoreline in the City of Sheboygan, from just south of Evergreen Avenue to the north corporate limits with unincorporated areas of Sheboygan County. *North American Vertical Datum 1988 (NAVD)
The hydraulic analyses for the previous FISs were based on unobstructed flow. The flood elevations shown on the profiles are thus considered valid only if hydraulic structures remain unobstructed, operate properly, and do not fail.
Roughness factors (Manning's "n") used in the hydraulic computations for Fisherman's Creek were chosen by engineering judgment based on field observation. Values ranged from 0.025 to 0.040 for the channel and from 0.070 to 0.20 for the overbanks.
Roughness coefficients (Manning's "n") for the Sheboygan and Mullet Rivers were furnished by the WDNR or were assigned on the basis of field inspection and aerial maps. The "n" values ranged from 0.020 to 0.055 for the channel and from 0.04 to 0.12 for the overbank areas. The slope-area method was utilized to determine starting water surface elevations.
Roughness coefficients for the channel of the North Branch Milwaukee River ranged from 0.02 to 0.07 and flood plain roughness values ranged from 0.025 to 0.10 for all floods.
23
Roughness coefficients for the channel of the North Branch Milwaukee River ranged from 0.02 to 0.07 and flood plain roughness values ranged from 0.025 to 0.10 for all floods.
Roughness coefficients (Manning's "n") for the Mullet River were obtained by field investigation. Average roughness values for the stream studied in detail ranged from 0.03 to 0.045 for the channel and 0.04 to 0.1 for the overbank.
Roughness factors (Manning’s “n”) used in the hydraulic computation were chosen by engineering judgment and were based on field observations of the streams and floodplain areas. Roughness factors for all streams studied by detailed methods are shown on Table 5, “Manning’s “n” Values.”
TABLE 5 – MANNING'S "N" VALUES
Stream Channel “n” Overbank “n”
Batavia Creek 0.020 – 0.055 0.040-0.120 Black River 0.020 – 0.055 0.040-0.120 Black River Tributary No. 2 0.020 – 0.055 0.040-0.120 Fisher Creek 0.020 – 0.055 0.040-0.120 Fisherman’s Creek 0.025-0.040 0.070-0.200 LaBudde Creek 0.020 – 0.055 0.040-0.120 Mullet River 0.020 – 0.055 0.040-0.120 North Branch Milwaukee River 0.020-0.070 0.025-0.100 Onion River 0.020 – 0.055 0.040-0.120 Pigeon River 0.020-0.055 0.040-0.120 Random Lake – Unnamed Tributary * * to Silver Creek Sheboygan River 0.020-0.055 0.040-0.120 Silver Creek * * * Data not available.
This Countywide Analysis:
There were no hydraulic models developed for this countywide study.
Flood hazard boundaries for flooding sources studied by detailed and approximate methods were revised based in improved topographic information.
Revised flood profiles were drawn showing the computed water-surface elevations for floods of selected recurrence intervals. In cases where the 2- and 1-percent annual chance flood elevations are close together, only the 1-percent annual chance profile was shown.
24 All elevations are referenced to the North American Vertical Datum of 1988 (NAVD 88). Elevation reference marks (ERMs) used in this study, and their descriptions, are shown on the FIRM. ERMs shown on the FIRM represent those used during the preparation of this and previous FISs. The elevations associated with each ERM were obtained and/or developed during FIS production to establish vertical control for determination of flood elevations and floodplain boundaries shown on the FIRM. Users should be aware that these ERM elevations may have changed since the publication of this FIS. To obtain up-to- date elevation information on National Geodetic Survey (NGS) ERMs shown on this map, please contact the Information Services Branch of the NGS at (301) 713-3242, or visit their website at www.ngs.noaa.gov. Map users should seek verification of non-NGS ERM monument elevations when using these elevations for construction or floodplain management purposes.
3.3 Vertical Datum
All FISs and FIRMs are referenced to a specific vertical datum. The vertical datum provides a starting point against which flood, ground, and structure elevations can be referenced and compared. Until recently, the standard vertical datum in use for newly created or revised FISs and FIRMs was the National Geodetic Vertical Datum of 1929 (NGVD 29). With the finalization of the North American Vertical Datum of 1988 (NAVD 88), many FIS reports and FIRMs are being prepared using NAVD 88 as the referenced vertical datum.
All flood elevations shown in this FIS report and on the FIRM are referenced to NAVD 88. Structure and ground elevations in the community must, therefore, be referenced to NAVD 88. It is important to note that adjacent communities may be referenced to NGVD 29. This may result in differences in base flood elevations across the corporate limits between the communities.
For information regarding conversion between the NGVD and NAVD, visit the National Geodetic Survey website at www.ngs.noaa.gov, or contact the National Geodetic Survey at the following address:
Vertical Network Branch, N/CG13 National Geodetic Survey, NOAA Silver Spring Metro Center 3 1315 East-West Highway Silver Spring, Maryland 20910 (301) 713-3191
Temporary vertical monuments are often established during the preparation of a flood hazard analysis for the purpose of establishing local vertical control. Although these monuments are not shown on the FIRM, they may be found in the Technical Support Data Notebook associated with the FIS report and FIRM for this community. Interested individuals may contact FEMA to access these data.
25
For this revision the vertical datum shift in Sheboygan County was calculated to be 0.0 feet NGVD 29 to NAVD 88. Structure and ground elevations in the community must, therefore, be referenced to NAVD 88.
4.0 FLOODPLAIN MANAGEMENT APPLICATIONS
The NFIP encourages State and local governments to adopt sound floodplain management programs. To assist in this endeavor, each FIS provides 1-percent annual chance floodplain data, which may include a combination of the following: 10-, 2-, 1-, and 0.2-percent annual chance flood elevations; delineations of the 1- and 0.2-percent annual chance floodplains; and 1-percent annual chance floodway. This information is presented on the FIRM and in many components of the FIS, including Flood Profiles, Floodway Data tables, and Summary of Stillwater Elevation tables. Users should reference the data presented in the FIS as well as additional information that may be available at the local community map repository before making flood elevation and/or floodplain boundary determinations.
4.1 Floodplain Boundaries
To provide a national standard without regional discrimination, the 1-percent annual chance flood has been adopted by FEMA as the base flood for floodplain management purposes. The 0.2-percent annual chance flood is employed to indicate additional areas of flood risk in the county. For the streams studied in detail, the 1- and 0.2-percent annual chance floodplain boundaries have been delineated using the flood elevations determined at each cross section. Between cross sections, the boundaries were interpolated using aerial photographs and topographic maps at scales of 1:24,000, 1:4800, 1:2400, and 1:1200 with contour intervals of 10, 4, and 2 feet, respectively (References 42-45, 56 and 57).
For this revision, and the November 21, 2002 revision for the City of Sheboygan and Sheboygan County Unincorporated Areas, for the areas with wave action, the boundaries were delineated using the 1-percent annual chance flood wave runup elevations determined at each transect and the 0.2-percent annual chance flood Lake Michigan flood levels (Reference 51). Between transects, the boundaries were interpolated using engineering judgment. Fifteen miles of the restudied coastline south of the City of Sheboygan were delineated on maps with 2-foot contour interval accuracy supplied by a private contractor (Reference 58). Even though wave heights and wave runup depths 3 feet or greater exist along the Lake Michigan shoreline, there are no coastal high hazard zone (Zone VE) areas included in the revised mapping for this revision. This is due primarily to the fact that the Zone VE hazard zone exists only at the shoreline and does not extend inland a sufficient distance such that it impacts structures or is feasible to map on the FIRM.
For the flooding sources studied by approximate methods, the boundaries of the 1-percent annual chance floodplains were delineated using topographic maps taken
26 from the previously printed FIS reports, FHBMs, and/or FIRMs for all of the incorporated and unincorporated jurisdictions within Sheboygan County.
For this countywide study, the 1- and 0.2-percent annual chance floodplain boundaries have been delineated using digital topographic data provided by Sheboygan County. This data includes 2005 orthophotography and contours at two foot intervals; referenced to the Wisconsin State Plane coordinate system, NAD83 horizontal datum, and NAVD 88 vertical datum.
The 1- and 0.2-percent annual chance floodplain boundaries are shown on the FIRM (Exhibit 2). On this map, the 1-percent annual chance floodplain boundary corresponds to the boundary of the areas of special flood hazards (Zones A and AE), and the 0.2-percent annual chance floodplain boundary corresponds to the boundary of areas of moderate flood hazards. In cases where the 1- and 0.2-percent annual chance floodplain boundaries are close together, only the 1-percent annual chance floodplain boundary has been shown. Small areas within the floodplain boundaries may lie above the flood elevations but cannot be shown due to limitations of the map scale and/or lack of detailed topographic data.
For the streams studied by approximate methods, only the 1-percent annual chance floodplain boundary is shown on the FIRM (Exhibit 2).
4.2 Floodways
Encroachment on floodplains, such as structures and fill, reduces flood-carrying capacity, increases flood heights and velocities, and increases flood hazards in areas beyond the encroachment itself. One aspect of floodplain management involves balancing the economic gain from floodplain development against the resulting increase in flood hazard. For purposes of the NFIP, a floodway is used as a tool to assist local communities in this aspect of floodplain management. Under this concept, the area of the 1-percent annual chance floodplain is divided into a floodway and a floodway fringe. The floodway is the channel of a stream, plus any adjacent floodplain areas, that must be kept free of encroachment so that the 1-percent annual chance flood can be carried without substantial increases in flood heights. Minimum federal standards limit such increases to 1.0 foot, provided that hazardous velocities are not produced. However, Wisconsin has established a more strict policy and does not allow any increase in the regional flood height for floodfringe developments (Reference 59). The floodways in this FIS are presented to local agencies as minimum standards that can be adopted directly or that can be used as a basis for additional floodway studies.
The floodways presented in this FIS were computed for certain stream segments on the basis of equal conveyance reduction from each side of the floodplain.
Floodway widths were computed at cross sections. Between cross sections, the floodway boundaries were interpolated. The results of the floodway computations
27 are tabulated for selected cross sections (Table 6). The computed floodways are shown on the FIRM (Exhibit 2). In cases where the floodway and 1-percent annual chance floodplain boundaries are either close together or collinear, only the floodway boundary is shown.
For selected streams in Table 6, the 1-percent annual chance floodplain and floodway were redelineated due to improved topographic data. As a result, there were areas where, based on the previous hydraulic analyses, the floodway would not fit within the redelineated boundaries of the 1-percent annual chance floodplain. In these areas, the floodway was also reduced to fit within the 1-percent annual chance floodplain boundary. The data provided in Table 6 lists the width of the floodway based on the hydraulic analyses previously done, as well as the amount of reduction needed to fit the redelineated floodway inside the redelineated 1-percent annual chance floodplain boundary. The redelineated floodways are shown on the FIRM (Exhibit 2).
Portions of the floodways for Fisher Creek, Pigeon River, Mullet River, Sheboygan River, Fisherman's Creek, and Black River Tributary No. 2 extend beyond the county boundary.
Near the mouths of streams studied in detail, floodway computations are made without regard to flood elevations on the receiving water body. Therefore, "Without Floodway" elevations presented in Table 6 for certain downstream cross sections of Black River, Black River Tributary No. 2, Fisherman's Creek, Mullet River, LaBudde Creek, Silver Creek, and Batavia Creek are lower than the regulatory flood elevations in that area, which must take into account the 1-percent annual chance flooding due to backwater from other sources.
Encroachment into areas subject to inundation by floodwaters having hazardous velocities aggravates the risk of flood damage, and heightens potential flood hazards by further increasing velocities. A listing of stream velocities at selected cross sections is provided in Table 6. In order to reduce the risk of property damage in areas where the stream velocities are high, the community may wish to restrict development in areas outside the floodway.
The area between the floodway and 1-percent annual chance floodplain boundaries is termed the floodway fringe. The floodway fringe encompasses the portion of the floodplain that could be completely obstructed without increasing the water-surface elevation of the 1-percent annual chance flood by more than 1.0 foot at any point. Typical relationships between the floodway and the floodway fringe and their significance to floodplain development are shown in Figure 2.
28 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
BATAVIA CREEK A 1,742 360 935 1.1 0 813.4 811.72 811.7 0.0 B 5,121 386 980 1.1 184 813.9 813.9 813.9 0.0 C 6,177 420 915 1.2 275 814.8 814.8 814.8 0.0 D 7,233 18 110 9.7 0 816.9 816.9 816.9 0.0 E 7,339 255 1,545 0.7 0 818.8 818.8 818.8 0.0 F 9,556 575 1,975 0.4 0 818.9 818.9 818.9 0.0 G 9,662 595 1,555 0.5 0 819.0 819.0 819.0 0.0 H 14,097 130 140 5.9 0 834.1 834.1 834.1 0.0 I14,836 60 270 3.0 0 842.4 842.4 842.4 0.0 J 14,889 35 210 3.9 0 842.4 842.4 842.4 0.0
BLACK RIVER A 52 130 295 8.5 0 584.3 580.53 580.5 0.0 B 1,003 250 1,000 2.5 0 584.3 583.13 583.1 0.0 C 1,584 400 1,390 1.8 0 584.3 583.33 583.3 0.0 D 2,270 375 1,255 2.0 0 584.3 583.53 583.5 0.0 E 3,115 50 365 6.8 0 584.3 584.13 584.1 0.0 F 3,801 575 2,270 1.1 0 585.2 585.2 585.2 0.0 G 5,438 360 1,365 1.8 0 585.5 585.5 585.5 0.0 H 6,758 300 1,025 2.0 0 586.2 586.2 586.2 0.0 I 8,236 200 840 2.5 0 587.8 587.8 587.8 0.0 J 8,448 45 355 5.9 0 587.8 587.8 587.8 0.0 K 8,659 275 1,225 1.7 0 588.6 588.6 588.6 0.0 L 10,296 1,085 3,315 0.6 0 589.0 589.0 589.0 0.0
1FEET ABOVE MOUTH 2ELEVATION COMPUTED WITHOUT CONSIDERATION OF BACKWATER EFFECTS FROM NORTH BRANCH MILWAUKEE RIVER 3ELEVATIONS COMPUTED WITHOUT CONSIDERING BACKWATER EFFECT FROM LAKE MICHIGAN TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS BATAVIA CREEK-BLACK RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
BLACK RIVER TRIBUTARY NO. 2 A 422 170 245 3.7 0 585.8 585.8 585.8 0.0 B 1,478 170 465 1.9 0 588.9 588.9 588.9 0.0 C 2,059 110 305 3.0 0 590.1 590.1 590.1 0.0 D 2,904 120 475 1.9 0 592.0 592.0 592.0 0.0 E 3,326 320 625 1.4 0 592.5 592.5 592.5 0.0 F 3,907 25 165 5.5 0 595.7 595.7 595.7 0.0 G 3,960 75 140 6.4 0 596.2 596.2 596.2 0.0 H 4,065 275 1,625 0.6 0 597.0 597.0 597.0 0.0 I 4, 910 85 125 727.2 0 601. 4 601. 4 601. 4 000.0 J 5,808 170 245 3.7 0 606.8 606.8 606.8 0.0 K 6,336 40 175 5.1 60 609.4 609.4 609.4 0.0 L 7,339 125 145 6.2 0 612.8 612.8 612.8 0.0 M 7,761 108 1,290 0.7 372 617.4 617.4 617.4 0.0
FISHER CREEK A 2,428 278 1,295 1.5 157 688.4 688.4 688.4 0.0 B 3,960 290 580 3.3 0 690.8 690.8 690.8 0.0 C 7,128 380 800 1.7 0 701.6 701.6 701.6 0.0 D 8,448 75 300 4.6 0 705.3 705.3 705.3 0.0 E 8,659 15 125 11.0 0 707.0 707.0 707.0 0.0 F 8,817 220 1,510 0.9 0 709.6 709.6 709.6 0.0 G 9,820 170 610 2.3 80 709.8 709.8 709.8 0.0 H 11,563 194 830 1.7 96 713.4 713.4 713.4 0.0
1FEET ABOVE MOUTH TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS BLACK RIVER TRIBUTARY NO. 2-FISHER CREEK 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
FISHER CREEK (CONTINUED) I 12,196 255 415 3.3 0 715.5 715.5 715.5 0.0 J 12,936 240 615 2.2 0 717.9 717.9 717.9 0.0 K 13,464 32 235 5.9 0 719.4 719.4 719.4 0.0 L 13,675 380 1,690 0.8 0 720.1 720.1 720.1 0.0 M 14,995 565 1,640 0.5 0 720.3 720.3 720.3 0.0 N 16,051 95 145 5.6 0 722.2 722.2 722.2 0.0 O 16,209 15 95 8.6 0 723.5 723.5 723.5 0.0
FISHERMAN'S CREEK A 160 269 634 4.9 0 584.3 582.42 582.4 0.0 B 560 350 572 5.8 0 584.3 583.52 583.5 0.0 C 740 455 1,120 5.0 0 586.6 586.6 586.6 0.0 D 2,230 800 2,467 3.1 0 587.8 587.8 587.8 0.0 E 4,105 190 728 8.2 0 592.3 592.3 592.3 0.0 F 4,415 155 1,062 3.7 110 593.6 593.6 593.6 0.0 G 4,555 354 1,037 4.7 0 593.6 593.6 593.6 0.0 H 5,310 188 536 9.8 0 595.9 595.9 595.9 0.0 I 6,550 230 734 6.1 0 601.0 601.0 601.0 0.0 J 8,020 51 389 8.7 121 604.9 604.9 604.9 0.0 K 9,610 244 795 6.7 0 610.3 610.3 610.3 0.0 L 11,720 93 345 9.1 40 617.6 617.6 617.6 0.0 M 12,940 66 280 7.9 23 625.8 625.8 625.8 0.0
1FEET ABOVE MOUTH 2ELEVATIONS COMPUTED WITHOUT CONSIDERING BACKWATER EFFECTS FROM LAKE MICHIGAN TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS FISHER CREEK-FISHERMAN'S CREEK 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
FISHERMAN'S CREEK (CONTINUED) N 14,280 106 249 8.7 0 632.0 632.0 632.0 0.0 O 14,850 317 1,760 1.4 0 636.4 636.4 636.4 0.0 P 15,290 116 601 2.8 0 636.5 636.5 636.5 0.0 Q 16,050 130 524 4.2 0 636.7 636.7 636.7 0.0 R 16,375 200 988 0.6 0 638.8 638.8 638.8 0.0 S 16,765 60 67 2.0 0 638.9 638.9 638.9 0.0
LA BUDDE CREEK A 686 585 2, 500 060.6 0 883. 7 881. 22 881. 2 000.0 B 2,851 385 1,750 0.8 0 883.7 881.72 881.7 0.0 C 3,326 415 1,785 0.8 0 884.2 884.2 884.2 0.0 D 5,596 210 800 1.8 0 885.6 885.6 885.6 0.0
MULLET RIVER A 580 120 685 5.5 0 674.8 671.53 671.5 0.0 B 686 80 540 7.1 0 674.8 671.63 671.6 0.0 C 4,276 320 655 5.8 0 677.0 677.0 677.0 0.0 D 9,451 405 695 5.5 0 686.4 686.4 686.4 0.0 E 16,104 200 735 5.2 0 696.5 696.5 696.5 0.0 F 22,017 385 1,245 3.0 0 705.0 705.0 705.0 0.0 G 26,822 525 1,415 2.7 0 714.2 714.2 714.2 0.0 H 32,524 185 470 8.1 0 723.7 723.7 723.7 0.0 I 36,220 70 615 6.2 0 728.7 728.7 728.7 0.0
1FEET ABOVE MOUTH 2ELEVATIONS COMPUTED WITHOUT CONSIDERING BACKGWATER EFFECTS FROM THE MULLET RIVER 3ELEVATIONS COMPUTED WITHOUT CONSIDERING BACKWATER EFFECT FROM SHEBOYGAN RIVER TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS FISHERMAN'S CREEK-MULLET RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
MULLET RIVER (CONTINUED) J 43,401 420 1,885 2.0 75 739.2 739.2 739.2 0.0 K 51,321 400 2,050 1.9 0 754.1 754.1 754.1 0.0 L 58,608 40 425 9.0 0 777.0 777.0 777.0 0.0 M 58,766 40 325 11.7 0 777.6 777.6 777.6 0.0 N 62,937 510 2,465 1.5 0 783.2 783.2 783.2 0.0 O 68,006 690 2,855 1.3 0 785.6 785.6 785.6 0.0 P 70,540 55 375 10.2 0 789.4 789.4 789.4 0.0 Q 74,236 135 1,680 1.9 0 804.1 804.1 804.1 0.0 R 75, 028 30 295 10. 9 0 806. 9 806. 9 806. 9 000.0 S 76,084 440 2,740 1.2 0 814.1 814.1 814.1 0.0 T 77,985 35 300 10.7 0 817.6 817.6 817.6 0.0 U 80,097 249 2,487 1.3 0 822.2 822.2 822.2 0.0 V 80,784 320 3,748 0.9 0 822.3 822.3 822.3 0.0 W 81,628 164 803 4.0 0 824.7 824.7 824.7 0.0 X 81,892 160 1,653 1.9 0 825.3 825.3 825.3 0.0 Y 82,632 175 1,195 2.7 0 826.2 826.2 826.2 0.0 Z 83,160 63 650 4.9 0 826.7 826.7 826.7 0.0 AA 83,740 55 529 6.0 0 830.4 830.4 830.4 0.0 AB 85,113 64 667 4.8 0 832.5 832.5 832.5 0.0 AC 85,377 304 2,360 1.4 0 836.8 836.8 836.8 0.0 AD 88,334 302 1,894 1.7 0 837.1 837.1 837.1 0.0 AE 90,076 520 1,900 1.7 0 837.4 837.4 837.4 0.0 AF 91,080 415 1,325 2.4 0 837.7 837.7 837.7 0.0
1FEET ABOVE MOUTH TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS MULLET RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
MULLET RIVER (CONTINUED) AG 92,452 415 1,670 1.9 0 840.7 840.7 840.7 0.0 AH 93,033 50 455 7.0 0 841.3 841.3 841.3 0.0 AI 95,832 325 2,685 1.2 0 849.0 849.0 849.0 0.0 AJ 98,472 285 525 5.8 0 851.2 851.2 851.2 0.0 AK 100,372 410 1,340 2.3 0 857.3 857.3 857.3 0.0 AL 100,636 355 1,700 1.8 0 860.1 860.1 860.1 0.0 AM 101,904 145 1,155 2.6 0 860.9 860.9 860.9 0.0 AN 102,009 65 730 4.2 0 863.3 863.3 863.3 0.0 AO 104, 491 285 1, 060 292.9 0 868. 3 868. 3 868. 3 000.0 AP 104,596 290 995 3.1 0 868.5 868.5 868.5 0.0 AQ 106,075 220 780 3.9 0 872.5 872.5 872.5 0.0 AR 106,497 360 3,960 0.8 0 883.4 883.4 883.4 0.0 AS 106,972 190 2,010 1.5 0 883.6 883.6 883.6 0.0 AT 107,078 29 2,740 1.1 0 883.7 883.7 883.7 0.0
NORTH BRANCH MILWAUKEE RIVER A 47,150 2,385 7,100 0.8 0 807.5 807.5 807.5 0.0 B 49,925 402 1,433 2.8 0 808.5 808.5 808.5 0.0 C 52,687 1,220 7,923 0.5 0 811.6 811.6 811.6 0.0 D 54,175 1,377 7,913 0.5 0 811.7 811.7 811.7 0.0 E 58,950 1,038 4,579 0.5 0 811.8 811.8 811.8 0.0 F 60,535 441 2,140 1.1 0 812.0 812.0 812.0 0.0
1FEET ABOVE MOUTH TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS MULLET RIVER-NORTH BRANCH MILWAUKEE RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
NORTH BRANCH MILWAUKEE RIVER (CONTINUED) G 61,060 274 1,604 1.5 0 812.2 812.2 812.2 0.0 H 63,440 568 1,876 1.0 0 813.3 813.3 813.3 0.0 I 66,450 520 1,959 1.0 0 814.0 814.0 814.0 0.0 J 68,315 369 1,223 1.6 0 814.5 814.5 814.5 0.0 K 69,684 47 374 5.2 0 815.3 815.3 815.3 0.0 L 70,080 415 1,809 1.1 0 816.0 816.0 816.0 0.0 M 112,430 355 832 1.2 330 845.6 845.6 845.6 0.0 N 113, 840 590 1, 019 101.0 0 850. 0 850. 0 850. 0 000.0 O 115,210 110 127 7.9 0 861.6 861.6 861.6 0.0 P 115,630 45 109 9.2 0 866.8 866.8 866.8 0.0 Q 116,180 45 258 3.9 0 872.5 872.5 872.5 0.0 R 117,160 175 285 3.5 0 877.1 877.1 877.1 0.0 S 118,160 315 1,022 1.0 0 886.1 886.1 886.1 0.0 T 118,800 415 2,540 0.4 0 889.4 889.4 889.4 0.0 U 119,710 410 1,128 0.9 0 889.5 889.5 889.5 0.0
ONION RIVER A 1,500 115 22 0 631.1 631.1 631.1 0.0 B 1,600 95 22 0 632.1 632.1 632.1 0.0 C 1,800 350 22 0 632.5 632.5 632.5 0.0 D 3,440 420 22 0 633.3 633.3 633.3 0.0 E 5,068 445 2,040 2.9 0 634.9 634.9 634.9 0.0
1FEET ABOVE MOUTH 2DATA NOT AVAILABLE TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS NORTH BRANCH MILWAUKEE RIVER-ONION RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
ONION RIVER (CONTINUED) F 7,867 825 3,755 1.6 0 638.0 638.0 638.0 0.0 G 14,203 355 1,580 3.8 0 645.4 645.4 645.4 0.0 H 18,480 555 2,050 2.9 0 656.5 656.5 656.5 0.0 I 20,803 235 840 7.1 0 666.5 666.5 666.5 0.0 J 21,120 95 875 6.8 0 669.4 669.4 669.4 0.0 K 21,489 158 645 9.3 32 670.2 670.2 670.2 0.0 L 24,604 1,075 3,265 1.8 0 677.5 677.5 677.5 0.0 M 26,822 150 635 9.4 0 680.0 680.0 680.0 0.0 N 30, 465 795 3, 495 171.7 0 686. 7 686. 7 686. 7 000.0 O 35,376 215 555 10.1 0 690.3 690.3 690.3 0.0 P 36,326 85 910 6.2 0 695.8 695.8 695.8 0.0 Q 36,432 155 1,135 4.9 0 695.8 695.8 695.8 0.0 R 38,491 170 1,245 4.5 0 698.4 698.4 698.4 0.0 S 43,401 790 4,955 1.1 0 701.1 701.1 701.1 0.0 T 45,936 340 1,945 2.9 0 701.8 701.8 701.8 0.0 U 47,308 285 1,675 3.3 0 703.1 703.1 703.1 0.0 V 47,572 145 1,510 3.7 0 704.3 704.3 704.3 0.0 W 47,678 320 2,215 2.5 0 704.3 704.3 704.3 0.0 X 50,107 1,120 4,970 1.1 0 706.1 706.1 706.1 0.0 Y 52,958 595 2,770 1.9 0 707.7 707.7 707.7 0.0 Z 54,859 520 2,295 2.4 0 709.7 709.7 709.7 0.0 AA 57,024 845 4,455 1.2 0 710.7 710.7 710.7 0.0 AB 57,604 360 1,900 2.8 0 710.8 710.8 710.8 0.0
1FEET ABOVE MOUTH TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS ONION RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
PIGEON RIVER A 633 235 875 5.9 135 584.3 583.82 583.8 0.0 B 2,904 165 1,035 5.0 0 584.3 583.82 583.8 0.0 C 4,435 150 855 6.0 0 585.1 585.1 585.1 0.0 D 4,593 95 500 10.3 0 585.1 585.1 585.1 0.0 E 4,857 125 975 5.3 0 586.8 586.8 586.8 0.0 F 5,966 125 815 6.3 0 588.4 588.4 588.4 0.0 G 6,124 60 535 9.6 0 588.4 588.4 588.4 0.0 H 6,283 40 455 11.3 0 591.3 591.3 591.3 0.0 I 6,758 85 990 5.2 0 594.0 594.0 594.0 0.0 J 6, 864 105 990 525.2 75 594. 5 594. 5 594. 5 000.0 K 8,553 290 1,330 3.9 0 598.1 598.1 598.1 0.0 L 13,464 690 1,665 3.1 0 608.3 608.3 608.3 0.0 M 17,371 215 1,190 4.3 0 614.8 614.8 614.8 0.0 N 17,529 128 830 6.2 0 614.9 614.9 614.9 0.0 O 17,635 105 910 5.7 0 615.4 615.4 615.4 0.0 P 17,793 190 860 6.0 0 615.5 615.5 615.5 0.0 Q 19,166 245 1,325 3.9 0 620.8 620.8 620.8 0.0 R 19,272 300 1,800 2.8 0 621.2 621.2 621.2 0.0 S 19,852 265 885 5.8 0 622.0 622.0 622.0 0.0 T 21,912 315 1,820 2.8 0 625.4 625.4 625.4 0.0 U 23,179 575 1,245 4.1 0 627.5 627.5 627.5 0.0 V 25,819 230 1,445 3.6 0 636.6 636.6 636.6 0.0 W 26,083 115 1,050 4.9 0 637.4 637.4 637.4 0.0 X 26,241 420 2,650 1.9 0 637.9 637.9 637.9 0.0
1FEET ABOVE MOUTH 2ELEVATION COMPUTED WITHOUT CONSIDERATION OF BACKWATER EFFECTS FROM LAKE MICHIGAN TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS PIGEON RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
PIGEON RIVER (CONTINUED) Y 26,980 530 1,880 2.5 0 639.0 639.0 639.0 0.0 Z 30,518 252 900 5.2 208 650.9 650.9 650.9 0.0 AA 33,897 390 1,565 3.9 0 661.3 661.3 661.3 0.0 AB 35,745 280 860 5.4 0 666.9 666.9 666.9 0.0 AC 35,956 230 730 6.4 0 668.1 668.1 668.1 0.0 AD 36,696 355 1,435 3.2 0 670.5 670.5 670.5 0.0 AE 38,280 175 995 4.7 0 672.3 672.3 672.3 0.0 AF 38,491 75 795 5.8 0 672.9 672.9 672.9 0.0 AG 38, 702 250 1, 185 393.9 0 673. 1 673. 1 673. 1 000.0 AH 41,184 600 2,785 1.7 0 675.6 675.6 675.6 0.0 AI 43,084 360 2,290 2.0 0 676.6 676.6 676.6 0.0 AJ 43,665 110 935 5.0 0 676.8 676.8 676.8 0.0 AK 43,771 85 830 5.6 0 677.0 677.0 677.0 0.0 AL 47,308 305 1,350 3.4 0 680.3 680.3 680.3 0.0 AM 48,734 185 1,320 3.5 0 682.3 682.3 682.3 0.0 AN 48,945 115 1,140 4.1 0 682.5 682.5 682.5 0.0 AO 49,051 300 2,095 2.2 0 682.8 682.8 682.8 0.0 AP 51,427 745 4,150 1.1 0 683.6 683.6 683.6 0.0
SHEBOYGAN RIVER A 800 364 7,978 1.3 0 584.3 579.62 579.6 0.0 B 3,385 284 2,671 3.8 0 584.3 579.62 579.6 0.0 C 4,095 252 2,618 3.9 0 584.3 579.72 579.7 0.0
1FEET ABOVE MOUTH 2ELEVATION COMPUTED WITHOUT CONSIDERATION OF BACKWATER EFFECTS FROM LAKE MICHIGAN TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS PIGEON RIVER-SHEBOYGAN RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
SHEBOYGAN RIVER (CONTINUED) D 5,995 430 2,003 5.1 0 584.3 580.52 580.5 0.0 E 7,050 248 1,492 6.8 0 584.3 581.42 581.4 0.0 F 7,920 231 1,611 6.3 0 584.3 582.62 582.6 0.0 G 8,350 195 1,710 6.0 0 584.3 583.72 583.7 0.0 H 8,635 289 2,364 4.3 0 584.3 584.22 584.2 0.0 I 9,450 280 2,178 4.7 0 584.6 584.6 584.6 0.0 J 11,275 258 2,153 4.7 0 585.4 585.4 585.4 0.0 K 12,350 226 2,264 4.5 0 586.0 586.0 586.0 0.0 L 13, 300 489 3, 737 272.7 61 586. 7 586. 7 586. 7 000.0 M 13,850 604 3,883 2.6 0 586.9 586.9 586.9 0.0 N 14,500 367 1,946 5.2 0 587.0 587.0 587.0 0.0 O 15,610 160 1,240 8.2 0 588.1 588.1 588.1 0.0 P 16,450 164 1,505 6.8 0 589.8 589.8 589.8 0.0 Q 17,545 158 2,897 3.5 357 591.2 591.2 591.2 0.0 R 18,040 99 1,252 8.1 0 591.4 591.4 591.4 0.0 S 19,970 195 1,784 5.7 0 594.0 594.0 594.0 0.0 T 21,470 134 1,536 6.6 0 598.0 598.0 598.0 0.0 U 23,100 250 2,203 4.6 0 599.6 599.6 599.6 0.0 V 27,245 400 2,939 3.5 0 602.8 602.8 602.8 0.0 W 29,475 515 3,266 3.1 141 605.0 605.0 605.0 0.0 X 38,760 260 1,993 5.1 0 611.3 611.3 611.3 0.0 Y 43,560 737 5,000 2.0 0 613.7 613.7 613.7 0.0 Z 47,720 196 1,709 6.0 0 615.5 615.5 615.5 0.0
1FEET ABOVE MOUTH 2ELEVATION COMPUTED WITHOUT CONSIDERATION OF BACKWATER EFFECTS FROM LAKE MICHIGAN TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS SHEBOYGAN RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
SHEBOYGAN RIVER (CONTINUED) AA 50,880 164 1,377 7.4 0 620.5 620.5 620.5 0.0 AB 55,460 224 2,353 4.3 0 626.0 626.0 626.0 0.0 AC 57,360 650 4,279 2.4 0 626.8 626.8 626.8 0.0 AD 65,880 809 2,804 3.6 0 628.9 628.9 628.9 0.0 AE 66,780 163 2,223 4.5 176 629.7 629.7 629.7 0.0 AF 68,180 364 2,010 3.7 0 631.9 631.9 631.9 0.0 AG 70,130 194 853 8.7 0 638.8 638.8 638.8 0.0 AH 70,480 146 757 9.9 0 655.6 655.6 655.6 0.0 AI 71, 480 189 1, 292 585.8 0 670. 4 670. 4 670. 4 000.0 AJ 72,335 147 1,627 4.6 0 671.3 671.3 671.3 0.0 AK 74,155 643 4,917 1.5 0 671.9 671.9 671.9 0.0 AL 75,995 269 2,278 3.3 0 672.1 672.1 672.1 0.0 AM 76,755 140 1,452 5.1 0 672.5 672.5 672.5 0.0 AN 82,000 688 3,933 1.4 0 677.1 677.1 677.1 0.0 AO 87,320 152 1,401 3.8 54 683.1 683.1 683.1 0.0 AP 91,120 176 1,384 3.9 0 687.8 687.8 687.8 0.0 AQ 95,475 208 1,728 3.1 302 692.3 692.3 692.3 0.0 AR 100,820 249 1,390 3.8 0 700.2 700.2 700.2 0.0 AS 106,450 267 1,409 3.8 0 705.8 705.8 705.8 0.0 AT 113,295 216 1,070 5.0 0 713.7 713.7 713.7 0.0 AU 119,500 550 2,767 1.9 0 721.0 721.0 721.0 0.0 AV 125,895 183 2,601 2.1 237 735.4 735.4 735.4 0.0 AW 131,100 1,517 5,520 1.0 0 736.9 736.9 736.9 0.0
1FEET ABOVE MOUTH TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS SHEBOYGAN RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
SHEBOYGAN RIVER (CONTINUED) AX 134,080 243 1,102 4.9 0 738.9 738.9 738.9 0.0 AY 134,370 665 1,791 3.0 0 739.9 739.9 739.9 0.0 AZ 139,655 560 2,461 2.2 198 745.8 745.8 745.8 0.0 BA 145,970 881 2,467 2.2 0 750.8 750.8 750.8 0.0 BB 150,140 1,151 4,906 1.1 0 753.2 753.2 753.2 0.0 BC 153,370 120 738 6.2 0 757.2 757.2 757.2 0.0 BD 156,800 98 643 7.1 0 762.8 762.8 762.8 0.0 BE 157,295 135 869 5.2 0 763.9 763.9 763.9 0.0 BF 157, 450 71 518 888.8 0 768. 2 768. 2 768. 2 000.0 BG 160,220 539 3,381 1.3 0 769.92 769.92 769.92 0.0 BH 165,790 310 948 4.8 0 772.12 772.12 772.12 0.0 BI 169,210 220 1,166 3.9 0 779.32 779.32 779.32 0.0 BJ 173,015 188 815 5.6 0 785.82 785.82 785.82 0.0 BK 176,825 128 755 6.0 0 793.72 793.72 793.72 0.0 BL 177,495 354 760 6.0 0 795.52 795.52 795.52 0.0 BM 178,195 175 1,733 2.6 0 798.02 798.02 798.02 0.0 BN 178,305 240 3,182 1.4 0 807.7 807.7 807.7 0.0 BO 183,470 162 1,012 4.5 120 808.1 808.1 808.1 0.0 BP 185,170 268 1,136 4.0 0 809.9 809.9 809.9 0.0 BQ 188,920 250 1,647 2.8 0 812.9 812.9 812.9 0.0 BR 193,370 151 1,079 3.6 0 815.6 815.6 815.6 0.0 BS 197,491 381 1,792 2.2 0 819.9 819.9 819.9 0.0 BT 199,950 245 1,060 3.7 0 821.3 821.3 821.3 0.0
1FEET ABOVE MOUTH 2ELEVATION WITHOUT CONSIDERING DAM-BREACH ANALYSIS TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS SHEBOYGAN RIVER 1-PERCENT-ANNUAL-CHANCE FLOOD FLOODING SOURCE FLOODWAY WATER SURFACE ELEVATION (FEET NAVD 88) WIDTH SECTION MEAN REDUCED WIDTH AREA VELOCITY WITHOUT WITH CROSS SECTION DISTANCE1 FROM PRIOR REGULATORY INCREASE (FEET) (SQUARE (FEET PER FLOODWAY FLOODWAY STUDY FEET) SECOND) (FEET)
SHEBOYGAN RIVER (CONTINUED) BU 202,000 249 1,006 3.9 0 823.7 823.7 823.7 0.0 BV 203,775 273 1,560 2.5 0 825.2 825.2 825.2 0.0 BW 205,725 182 538 7.2 0 826.6 826.6 826.6 0.0 BX 208,434 192 1,105 3.5 0 832.2 832.2 832.2 0.0 BY 209,435 100 584 6.6 0 836.5 836.5 836.5 0.0 BZ 210,405 565 3,117 1.2 0 837.7 837.7 837.7 0.0 CA 211,145 300 2,057 1.9 0 838.3 838.3 838.3 0.0 CB 212,275 476 1,538 2.5 0 839.2 839.2 839.2 0.0
SILVER CREEK A 739 850 1,580 1.5 0 808.2 806.32 806.3 0.0 B 2,640 920 1,715 1.4 0 808.2 807.22 807.2 0.0 C 2,798 870 2,865 0.8 0 808.2 807.22 807.2 0.0 D 5,174 280 1,150 2.1 0 814.7 814.7 814.7 0.0 E 5,596 320 1,545 1.6 0 818.9 818.9 818.9 0.0 F 6,494 140 335 7.3 0 825.1 825.1 825.1 0.0 G 7,128 185 700 3.5 0 829.3 829.3 829.3 0.0 H 10,190 260 540 4.5 0 840.8 840.8 840.8 0.0 I 10,718 285 860 2.2 0 842.5 842.5 842.5 0.0 J 11,299 580 1,730 1.1 0 847.9 847.9 847.9 0.0 K 12,196 430 1,810 1.1 180 848.4 848.4 848.4 0.0 L 13,886 800 2,720 0.7 0 848.9 848.9 848.9 0.0 M 14,097 1,110 2,825 0.7 0 848.9 848.9 848.9 0.0
1FEET ABOVE MOUTH 2ELEVATION COMPUTED WITHOUT CONSIDERATION OF BACKWATER EFFECTS FROM NORTH BRANCH MILWAUKEE RIVER TABLE 6 FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SHEBOYGAN COUNTY, WI AND INCORPORATED AREAS SHEBOYGAN RIVER-SILVER CREEK FIGURE 2 – FLOODWAY SCHEMATIC
5.0 INSURANCE APPLICATIONS
For flood insurance rating purposes, flood insurance zone designations are assigned to a community based on the results of the engineering analyses. The zones are as follows:
Zone A
Zone A is the flood insurance rate zone that corresponds to the 1-percent annual chance floodplains that are determined in the FIS by approximate methods. Because detailed hydraulic analyses are not performed for such areas, no base flood elevations or depths are shown within this zone.
Zone AE
Zone AE is the flood insurance rate zone that corresponds to the 1-percent annual chance floodplains that are determined in the FIS by detailed methods. In most instances, whole-foot base flood elevations derived from the detailed hydraulic analyses are shown at selected intervals within this zone.
Zone AO
Zone AO is the flood insurance rate zone that corresponds to the areas of 1-percent annual chance shallow flooding (usually sheet flow on sloping terrain) where average depths are between 1 and 3 feet. Average whole-foot depths derived from the detailed hydraulic analyses are shown within this zone.
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Zone X
Zone X is the flood insurance rate zone that corresponds to areas outside the 0.2- percent annual chance floodplain, areas within the 0.2-percent annual chance floodplain, and to areas of 1-percent annual chance flooding where average depths are less than 1 foot, areas of 1-percent annual chance flooding where the contributing drainage area is less than 1 square mile, and areas protected from the 1- percent annual chance flood by levees. No base flood elevations or depths are shown within this zone.
6.0 FLOOD INSURANCE RATE MAP
The FIRM is designed for flood insurance and floodplain management applications.
For flood insurance applications, the map designates flood insurance rate zones as described in Section 5.0 and, in the 1-percent annual chance floodplains that were studied by detailed methods, shows selected whole-foot base flood elevations or average depths. Insurance agents use the zones and base flood elevations in conjunction with information on structures and their contents to assign premium rates for flood insurance policies.
For floodplain management applications, the map shows by tints, screens, and symbols, the 1- and 0.2-percent annual chance floodplains. Floodways and the locations of selected cross sections used in the hydraulic analyses and floodway computations are shown where applicable.
The current FIRM presents flooding information for the entire geographic area of Sheboygan County. Previously, separate FIRMs, FHBMs and FBFMs were prepared for each identified flood-prone incorporated community and the unincorporated areas of the county. Historical data relating to the maps prepared for each community, up to and including this countywide FIS, are presented in Table 7, "Community Map History."
7.0 OTHER STUDIES
FIS have been prepared for the unincorporated areas of Manitowoc County, Calumet County, Fon Du Lac County, Washington County, and the incorporated areas of Ozaukee County, Wisconsin (References 60-63).
This FIS report supersedes or is compatible with all previous studies on streams, FBFM and FHBM in the incorporated and unincorporated areas of Sheboygan County, (References 1- 13) and should be considered authoritative for purposes of the NFIP.
44 FLOOD HAZARD FLOOD INSURANCE FLOOD INSURANCE COMMUNITY NAME INITIAL IDENTIFICATION BOUNDARY MAP RATE MAP RATE MAP REVISION DATE(S) EFFECTIVE DATE REVISION DATE(S)
*Adell, Village of N/A None N/A None
Cascade, Village of May 3, 1974 April 15, 1977 October 15, 1981 None
Cedar Grove, Village of April 2, 2009 None April 2, 2009 None
*Elkhart Lake, Village of N/A None N/A None
Glenbeulah, Village of April 2, 2009 None April 2, 2009 None
Howards Grove, Village of April 2, 2009 None April 2, 2009 None
Kohler, Village of February 1, 1974 April 23, 1976 April 2, 1991 None February 19, 1982
Oostburg, Village of June 28, 1974 June 4, 1976 April 2, 2009 None
45 Plymouth, City of November 1, 1974 None July 5, 1983 None
Random Lake, Village of June 28, 1974 August 6, 1976 April 1, 1981 None August 12, 1977
Sheboygan, City of June 7, 1974 April 25, 1975 March 15, 1977 December 2, 1988 April 2, 1991 November 21, 2002
*No Special Flood Hazard Areas Identified
T A FEDERAL EMERGENCY MANAGEMENT AGENCY B L SHEBOYGAN COUNTY, WI COMMUNITY MAP HISTORY E AND INCORPORATED AREAS 7
FLOOD HAZARD FLOOD INSURANCE FLOOD INSURANCE COMMUNITY NAME INITIAL IDENTIFICATION BOUNDARY MAP RATE MAP RATE MAP REVISION DATE(S) EFFECTIVE DATE REVISION DATE(S)
Sheboygan Falls, City of November 30, 1973 April 30, 1976 April 2, 1991 None
Sheboygan County July 17, 1978 None July 17, 1978 December 16, 1988 (Unincorporated Areas) September 3, 1992 November 21, 2002
Waldo, Village of December 6, 1974 August 8, 1975 May 1, 1987 None
*No Special Flood Hazard Areas Identified
T A FEDERAL EMERGENCY MANAGEMENT AGENCY B L SHEBOYGAN COUNTY, WI COMMUNITY MAP HISTORY E AND INCORPORATED AREAS 7
8.0 LOCATION OF DATA
Information concerning the pertinent data used in the preparation of this FIS can be obtained by contacting Federal Insurance and Mitigation Division, FEMA Region V, 536 South Clark Street, Sixth Floor, Chicago, Illinois 60605.
9.0 BIBLIOGRAPHY AND REFERENCES
1. Federal Emergency Management Agency, Flood Insurance Study, City of Plymouth, Sheboygan County, Wisconsin, Washington, D.C., January 5, 1983.
2. U.S. Department of Housing and Urban Development, Federal Insurance Administration, Flood Insurance Study, City of Sheboygan, County of Sheboygan, Wisconsin, Washington, D.C., September 15, 1976 (FIS report), March 15, 1977 (FIRM).
3. Federal Emergency Management Agency, Flood Insurance Study, City of Sheboygan, Sheboygan County, Wisconsin, Washington, D.C., December 2, 1988.
4. Federal Emergency Management Agency, Flood Insurance Study, City of Sheboygan, Sheboygan County, Wisconsin, Washington, D.C., April 2, 1991.
5. Federal Emergency Management Agency, Flood Insurance Study, City of Sheboygan, Sheboygan County, Wisconsin, Washington, D.C., November 21, 2002.
6. Federal Emergency Management Agency, Flood Insurance Study, City of Sheboygan Falls, Sheboygan County, Wisconsin, Washington, D.C., April 2, 1991.
7. Federal Emergency Management Agency, Flood Insurance Study, Sheboygan County, Wisconsin (Unincorporated Areas), Washington, D.C., December 16, 1988.
8. Federal Emergency Management Agency, Federal Insurance Administration, Flood Insurance Study, Village of Cascade, Sheboygan County, Wisconsin, April 15, 1981.
9. Federal Emergency Management Agency, Flood Insurance Study, Village of Kohler, Sheboygan County, Wisconsin, Washington, D.C., April 2, 1991.
10. Federal Emergency Management Agency, Federal Insurance Administration, Flood Insurance Study, Village of Random Lake, County of Sheboygan, Wisconsin, October 1, 1980.
11. U.S. Department of Housing and Urban Development, Federal Insurance Administration, Flood Insurance Study, County of Sheboygan, Unincorporated Areas, Wisconsin, March 1977.
12. Federal Emergency Management Agency, Flood Insurance Study, Sheboygan County, Wisconsin (Unincorporated Areas), Washington, D.C., September 3, 1992.
47
13. Federal Emergency Management Agency, Flood Insurance Study, Sheboygan County, Wisconsin (Unincorporated Areas), Washington, D.C., November 21, 2002.
14. U.S. Department of Commerce, Bureau of the Census, Census of Population, Number of Inhabitants, Wisconsin, Washington, D.C.
15. U.S. Department of Agriculture, Soil Conservation Service, Sheboygan County, Interim Soil Survey Report, Part 2, June 1973.
16. U.S. Department of the Interior, Geological Survey, Water Resources Data for Wisconsin, 1968-1975.
17. Wisconsin Department of Natural Resources, Sheboygan Geographical Management Unit (GMU) Integrated Environmental Management (IEM) Projects, Franklin Dam Removal; http://dnr.wi.gov/org/gmu/sidebar/iem/sheboygan/index.htm.
18. U.S. Department of Agriculture, Soil Conservation Service, "Hydrology," National Engineering Handbook, Section 4, 1972.
19. U.S. Department of the Interior, Geological Survey, Open-File Report, Estimating Magnitude and Frequency of Floods in Wisconsin, D. H. Conger, 1971.
20. U.S. Department of Agriculture, Soil Conservation Service, Soil and Water Conservation Service District, Soils Interpretations - A Guide to Land Use and Conservation Planning, Manitowoc County, Wisconsin, 1973.
21. U.S. Department of Commerce, Weather Bureau, Technical Paper No. 40, Rainfall Frequency Atlas of the United States, Washington, D.C., January 1963.
22. U.S. Department of the Army, Corps of Engineers, Baltimore District, "Principles and Determinations," Unit Hydrographs, Part 1, 1963.
23. U.S. Department of Agriculture, Soil Conservation Service, Technical Release No. 55, Urban Hydrology for Small Watersheds, Washington, D.C., January 1975.
24. U.S. Army Corps of Engineers, Hydrologic Engineering Center, HEC-1 Flood Flow Frequency Analysis, Computer Program 823-X6-L2610, Davis, California, January 1973.
25. U.S. Army Corps of Engineers, Flood Plain Information, Sheboygan River and Mullet River, Sheboygan County, Wisconsin, August 1971.
26. U.S. Water Resources Council, Bulletin No. 15, A Uniform Technique for Determining Flood Flow Frequencies, December 1967.
48
27. U.S. Department of the Army, Corps of Engineers, Chicago District, Flood Plain Information. Sheboygan County. Wisconsin, (with backup hydrologic data), August 1971.
28. Southeastern Wisconsin Regional Planning Commission, Planning Report No. 13, A Comprehensive Plan for the Milwaukee River Watershed, October 1971.
29. U.S. Department of Agriculture, Soil Conservation Service, Computer Program for Project Formulation-Hydrology, Technical Release No. 20, May 1965.
30. U.S. Army Corps of Engineers, Hydrologic Engineering Center, HEC-1 Flood Hydrograph Package, User's Manual, Davis, California, September 1981, revised January 1985.
31. U.S. Geological Survey, Water Resource Investigations Report 80-1214, Techniques for Estimating Magnitude and Frequency of Floods for Wisconsin Streams, D. H. Conger, 1981.
32. U.S. Army Corps of Engineers, Hydrologic Engineering Center, HEC-1 Flood Hydrograph Package, Computer Program 723-X6-L2010, Davis, California, September 1981, revised January 1985.
33. U.S. Army Corps of Engineers, Hydrologic Engineering Center, Flood Flow Frequency Analysis, Computer Program 723-X6-L7550, Davis, California, December 1983.
34. U.S. Army Corps of Engineers, Coastal Engineering Research Center, Waterways Experiment Station, Jon J. Hubertz, David B. Driver, and Robin D. Reinhard, Hindcast Wave Information for the Great Lakes: Lake Michigan, WIS Report 24, Vicksburg, Mississippi October 1991.
35. Federal Emergency Management Agency, Guidelines and Specifications for Wave Elevation Determination and V Zone Mapping-Great Lakes, Draft Report, August 1996, unpublished.
36. U.S. Department of the Army, Corps of Engineers, HEC-2 Water-Surface Profiles, with Modification 58, February 1976.
37. Wisconsin Department of Transportation, Miscellaneous Bridge Plans, I-43, 1976, preliminary.
38. Wisconsin Department of Transportation, County Trunk Highway A Over Sheboygan River, Structure B-59-49, 1969.
39. Wisconsin Department of Transportation, Bridge Plans for State Trunk Highway 23 Over Sheboygan River, Structure B-59-8U89, 1975.
40. Sheboygan County, Wisconsin Highway Department, State Project No. 4233-2-71, Bridge Plans for County Trunk Highway EH, 1971.
49
41. Sheboygan County, Sheboygan County Flood Plain Maps, Pigeon River and Onion River Scale 1:2,400, Contour Interval 2 Feet, October 5, 1973.
42. Housing and Urban Development, Federal Insurance Administration, Flood Insurance Study, Manitowoc County, Wisconsin (Unincorporated Areas), Washington, D.C., March 15, 1978 (FIS report), September 15,1978 (FIRM).
43. U.S. Department of the Interior, Geological Survey, 7.5-Minute Series Topographic Maps, Scale 1:24,000, Contour Interval 10 Feet: Manitowoc, Wisconsin, 1954; School Hill, Wisconsin, 1954; Cleveland East, Wisconsin, 1954; Cleveland West, Wisconsin, 1954; Franklin, Wisconsin, 1954; Howards Grove, Wisconsin, 1954; Sheboygan North, Wisconsin, 1954; Sheboygan South, Wisconsin, 1954; Sheboygan Falls, Wisconsin, 1954.
44. U.S. Department of the Interior, Geological Survey, 15-Minute Series Topographic Maps, Scale 1:62,500, Contour Interval 20 Feet: Kiel, Wisconsin, 1954; Kewaskum, Wisconsin, 1955; Sheboygan Falls, Wisconsin, 1954.
45. U.S. Department of the Interior, Geological Survey, 7.5-Minute Series Topographic Maps, Advanced Prints Unpublished, Scale 1:24,000, Contour Interval 10 Feet: Elkhart Lake, Wisconsin, 1974; Plymouth South, Wisconsin, 1974.
46. U.S. Water Council, Hydrology Committee, Bulletin No. 14, River Mileage Measurement, Revised October 1968.
47. Aero-Metric Engineering, Inc., Orthophoto of the City of Sheboygan, Scale 1:1,200, Contour Interval 2 Feet, Sheboygan, Wisconsin, June 1981.
48. U.S. Army Corps of Engineers, Hydrologic Engineering Center, HEC-2 Water-Surface Profiles, Generalized Computer Program, Davis, California, April 1984.
49. U.S. Army Corps of Engineers, Hydrologic Engineering Center, HEC-2 Water-Surface Profiles, Generalized Computer Program, Davis, California, May 1991.
50. U.S. Army Corps of Engineers, Sacramento District, Computer Program 22-J2-L212, Backwater-Any Cross Section, October 1966.
51. U.S. Army Corps of Engineers, Detroit District, Phase I, Revised Report on Great Lakes Open-Coast Flood Levels, April 1988.
52. U.S. Geological Survey, 7.5 Minute Series Topographic Maps, Scale 1:24000, Contour Interval 20 feet: Sheboygan Falls, Wisconsin, 1954.
53. U.S. Department of Agriculture, Soil Conservation Service, Soil Survey of Sheboygan County, Wisconsin, January 1978.
50
54. U.S. Department of Housing and Urban Development, Federal Insurance Administration, Flood Hazard Boundary Map, Village of Random Lake, Wisconsin, August 1977.
55. U.S. Army Corps of Engineers, Detroit District, Franklin Dam, Sheboygan River, Sheboygan County, Wisconsin, Dam Failure Analysis, December 1988.
56. U.S. Department of the Interior, Geological Survey, 7.5-Minute Series Topographic Maps, Advanced Prints Unpublished, Scale 1:24,000, Contour Interval 10 Feet: Batavia, Wisconsin, 1974.
57. U.S. Geological Survey, 7.5 Minute Series Topographic Maps, Scale 1:24,000, Contour Interval 10 Feet: Sheboygan South, Wisconsin, 1954, photo revised 1973; Sheboygan North, Wisconsin, 1954, Sheboygan Falls, Wisconsin, 1954, photo revised 1973; Howards Grove, Wisconsin, 1954, photo revised 1973; Franklin, Wisconsin, 1954, photo revised 1973; and Batavia Wisconsin, 1974.
58. Gourdie/Fraser and Associates, Digital Mapping of the Sheboygan County Shoreline, Scale 1"=100', June 1993.
59. State of Wisconsin Administrative Code, NR 116.13d.
60. Federal Emergency Management Agency, Flood Insurance Study, Calumet County, Wisconsin (Unincorporated Areas), Washington, D.C., May 3,1982.
61. Federal Emergency Management Agency, Flood Insurance Study, Fond Du Lac County, Wisconsin (Unincorporated Areas), Washington, D.C., June 6, 2000.
62. Federal Emergency Management Agency, Flood Insurance Study, Washington County, Wisconsin (Unincorporated Areas), Washington, D.C., September 1, 1983.
63. Federal Emergency Management Agency, Flood Insurance Study, Ozaukee County, Wisconsin and Incorporated Areas, Washington, D.C., December 6, 1999.
State of Wisconsin, Department of Transportation, Aerial Photographs by Town and Range, Scale l:12000, Sheboygan County, 1966.
U.S. Army Corps of Engineers, Hydro1ogic Engineering Center, Computer Program 723- X6-L202A HEC-2 Water-Surface Profiles, Davis, California, December 1968, with updates.
Aero-Metric Engineering, Inc., Topographic Maps, Scale 1:1200, Contour Interval 2 feet, City of Kohler, Wisconsin, November 1969.
Aero-Metric Engineering, Inc, Topographic Mapping, Scale 1:1200, Contour Interval 2 feet: City of Plymouth, Wisconsin, April 1971.
51
U.S. Geological Survey, 7.5 Minute Series Topographic Maps, Scale 1:24,000, Contour Interval 10 Feet: Howards Grove, Wisconsin, 1954, photo revised 1973; Sheboygan Falls, Wisconsin, 1954, photo revised 1973; Sheboygan North, Wisconsin, 1954, photo revised 1973; Sheboygan South, Wisconsin, 1954, photo revised 1973.
Aero-Metric Engineering, Inc., Flood Plain Zoning Map, Scale 1:4800, Contour Interval 2 feet: Sheboygan Falls, Wisconsin, November 1974.
Park Aerial Surveys, Inc., Aerial Photographs, Scale 1:4800, Village of Cascade, Wisconsin, May 1975.
U.S. Army Corps of Engineers, Flood Flow Frequency Analysis, Generalized Computer Program 723-X6-L7550, Davis, California, June 1976.
Southeastern Wisconsin Regional Planning Commission, Topographic Maps, Scale 1:2400, Contour Interval four feet: Village of Random Lake, Wisconsin, 1975, (revised) 1978.
Owen Ayres and Associates, Digital Files of the City of Sheboygan Shoreline, Scale 1:1,200, Contour Interval 2 Feet, April 1992.
52