Discovery Report Lower Kansas Watershed, HUC 10270104 Atchison, Douglas, Jefferson, Johnson, Leavenworth, Osage, Shawnee, Wabaunsee, and Wyandotte Counties, KS & Kansas City (Jackson County), MO Report Number 01 8/20/2012 Project Area Community List Community Name Community Name Atchison County, KS Johnson County, KS (cont.) Atchison County Unincorporated Areas City of Overland Park City of Atchison City of Roeland Park City of Effingham City of Shawnee City of Lancaster Johnson County Unicorporated Areas Douglas County, KS Leavenworth County, KS City of Baldwin City City of Basehor City of Eudora City of Easton City of Lawrence City of Linwood City of Lecompton City of Tonganoxie Douglas County Unincorporated Areas Leavenworth County Unincorporated Areas Jackson County, MO Osage County, KS City of Kansas City City of Carbondale Jefferson County, KS City of Overbrook City of McLouth Osage County Unincorporated Areas City of Perry Shawnee County, KS City of Winchester City of Auburn Jefferson County Unincorporated Areas City of Topeka Johnson County, KS Shawnee County Unincorporated Areas City of De Soto Wabaunsee County, KS City of Gardner Wabaunsee County Unicorporated Areas City of Lake Quivira Wyandotte County, KS City of Lenexa City of Bonner Springs City of Merriam City of Edwardsville City of Mission City of Kansas City/Wyandotte County Unified Government City of Olathe i Table of Contents I. General Information ............................................................................................ 3 II. Watershed Stakeholder Coordination .................................................................. 6 III. Data Analysis ....................................................................................................... 7 i. Data that can be used for Flood Risk Products .................................................... 8 ii. Other Data and Information ............................................................................... 12 IV. Discovery Meeting ............................................................................................ 14 V. RiskMAP Project Scope .................................................................................... 16 VI. Appendices ........................................................................................................ 18 Figures Figure 1: Lower Kansas Watershed ....................................................................................... 4 Tables Table 1: CNMS categorized stream mileage ......................................................................... 5 Table 2: Data Type and Sources Collected for the Lower Kansas ........................................ 7 Table 3: Lower Kansas Watershed Gages with Peak Flow ................................................... 9 Table 4: Hazard Mitigation Plan Actions Summary ............................................................ 13 Table 5: Lower Kansas Discovery Meetings ....................................................................... 14 Table 6: Discovery Meeting Discussion Topics .................................................................. 15 Table 7: Scope of Work ....................................................................................................... 16 Financial assistance was provided to the Kansas Department of Agriculture – Division of Water Resources by the Department of Homeland Security’s Federal Emergency Management Agency to prepare this publication. The assistance was provided through Cooperative Agreement EMK-2011- CA-1107 as part of the Cooperating Technical Partner Program. This publication does not necessarily reflect the views of FEMA. ii I. General Information The purpose of this Discovery Report is to provide a foundation for potential future Federal Emergency Management Agency (FEMA) flood risk projects. The Discovery process is part of the FEMA Risk Mapping, Assesment and Planning (RiskMAP) program, which is considered on a watershed, developed from HUC-8 boundaries, basis rather than a community or county-wide basis. The RiskMAP program is designed to deliver quality data, increase public awareness of flood risk, and encourage local/regional actions that reduce risk by working with stakeholders. To qualify for a RiskMAP project, a watershed has to go through the Discovery process first. Discovery provides for the exchange of information between local, state, federal, and private-sector stakeholders, and includes meetings with stakeholders to better understand the watershed, decide whether a flood risk project is appropriate, and if so, collaborate on the project planning in detail. This report, along with the Discovery map, summarizes the information gathered as part of the Discovery process, what the challenges and issues the watershed and communities face, and what products or actions would be useful or are necessary for the community in reducing their flood risk. The Lower Kansas Watershed was selected to go through Discovery because there is increasing population, identified flood risks and identified mitigation projects. The watershed is primarily located in Northeast Kansas, with a small portion extending into Northwest Missouri. It is approximately 1,666 square miles and includes (at least partially) nine counties and 33 communities. Portions of Atchison, Douglas, Jefferson, Johnson, Leavenworth, Osage, Shawnee, Wabaunsee, and Wyandotte Counties in Kansas are located in the watershed. The Cities of Auburn, Carbondale, De Soto, Easton, Edgerton, Edwardsville, Effingham, Eudora, Gardner, Lake Quivira, Lawrence, Linwood, Merriam, Nortonville, Shawnee, Tonganoxie and Winchester are entirely located in the watershed. Portions of the Cities of Atchison, Baldwin City, Basehor, Bonner Springs, Kansas City, Lancaster, Lecompton, Lenexa, McLouth, Mission, Olathe, Overbrook, Overland Park, Perry, Roeland Park, and Topeka in Kansas and the City of Kansas City, Missouri, are located in the watershed. Please note that the City of Kansas City, Missouri, is located in Jackson County, Missouri, but the portion of the watershed extending into Missouri is entirely contained within the coporate limits of the City of Kansas City, Missouri. The main river of the watershed is the Kansas River, which flows into the Missouri River at the Kansas and Missouri state boundary. It is a major flooding source for the watershed and runs through the middle of the watershed. Several tributaries flow directly into the Kansas River and contribute to flooding in the area, but there are two primary tributaries flowing into the Kansas River that are major flooding sources. Stranger Creek starts in the north end of the Watershed in Atchison County and flows into the Kansas River near the City of Linwood. Wakarusa River starts in the west end of the watershed in Shawnee County and flows into the Kansas River near the City of Eudora. Clinton Lake is on the Wakarusa River and is the largest lake in the watershed. It is operated and maintained by the U.S. Army Corps of Engineers Kansas City District, and it has a drainage area of 367 square miles. The terrain generally consists of gentle to moderate slopes. 3 Lower Kansas Watershed Discovery Report Figure 1: Lower Kansas Watershed This watershed is experiencing rapid growth in population. Most of the counties in the watershed experienced an increase in population from 2000 to 2010, according to the 2010 Census. Osage and Wyandotte Counties were the only counties that declined in population, with 2.5 percent and 0.2 percent decreases, respectively. Three counties increased at a higher rate than the Kansas state average of 6.1 percent population growth. Douglas, Leavenworth and Johnson population increase by 10.9 percent, 11 percent and 20.6 percent, respectively. The population in the City of Kansas City, Missouri, increase by 4.1 percent, which is below the Missouri state average of 7.0 percent. At least four cities in the watershed experienced greater that a 25 percent increase in population from 2000 to 2010. The cities of De Soto, Gardner, Olathe and Shawnee grew by 25.4 percent, 103.5 percent, 35.4 percent and 29.6 percent, respectively. Five of the six most populous counties in Kansas are at least partially included in this watershed. Johnson has a population 544,129 and is the most populated county in the state. Shawnee has a population of 177,934 and is the third largest county in the state. Wyandotte has a population of 157,505 and is the fourth largest county in the state. Douglas has a population of 110,826 and is the fifth largest county in the state. Leavenworth has a population of 76,227 and is the sixth largest county in the state. Kansas City, Missouri, is the largest city in Missouri with a population of 459,787. Overall, there are 1,126,019 people in the nine counties in Kansas, and 1,585,806 people with Kansas City, Missouri, included. Information about the flood study needs within the state of Kansas and Missouri was gathered from the Coordinated Needs Management Strategy (CNMS) database. The purpose of CNMS is to assess the need to revise and update flood hazard information. The CNMS process determines whether existing flood hazard studies are valid, by evaluating both natural and man-made changes that affect the floodplain. Analysis is preformed on gage, 4 modeling methodology, new or removed flood control and hydraulic structures, channel reconfiguration, channel fill and scour, rural versus urban regression equations, land use changes, the availability of better topography, and significant storms.