Image: Kansas Department of Agriculture

Kansas - Lower Republican Basin
Wetland Environments
Molly Reardon, Marco Allain, Kyle Jackson
Spring 2012

Introduction Location Problems Conclusion References


The three major tributaries of the Republican River Basin originate on the high plains of northeastern Colorado. The tributaries converge to form the main branch of the Republican River which flows eastward along the northern border of Kansas and then turns south into the Smoky Hills region of Kansas. The section of river which flows through Kansas is commonly called, the Lower Republican River Basin. This report will focus on past environmental problems, and explore environmental management practices and progress within the Lower Republican River Basin.

Image: Kansas Water Office


The Kansas-Lower Republican (KLR) River Basin slopes gently from the west to east. Elevation in the basin ranges from 400 meters (1300 feet) to about 625 meters (2050 feet). The population within the basin is the largest of all twelve river basins in Kansas. As of the year 2000, 1,025,644 residents lived within the basin. Population within the last 40 years, has shown a trend toward urbanization. Agriculture is the primary economy in the rural portions of the basin, while commercial industry dominates the urban regions. Land use in the region is dominated by agriculture, however oil, natural gas, coal, stone quarrying, and managed grasslands are found in the region as well. Major cities include Junction City, Topeka, Manhattan, Lawrence, and Kansas City (Kansas Water Office).

The KLR Basin is an area of about 27,500 square kilometers (10,600 square miles) in northeast and north-central Kansas. Terrain in the basin generally has gentle to moderate slopes of less than 12 percent (Kansas Water Resources Board, 1959, 1961). Soil permeability ranges from about 0.76 centimeters per hour (0.3 inches per hour) to 17.5 centimeters per hour (6.9 inches per hour), with a mean of about 2 centimeters per hour (0.8 inches per hour), and is generally lower in the central and eastern parts of the basin (U.S. Department of Agriculture, 1993). Principal tributaries to the KLR main branch include White Rock Creek, Big Blue River, Mill Creek in Wabaunsee County, Vermillion Creek in Pottawatomie County, Soldier Creek, Delaware River, Wakarusa River, and Horseshoe Creek. Major Federal reservoirs in the basin include Milford Lake on the Republican River, Tuttle Creek Lake on the Big Blue River, Perry Lake on the Delaware River, and Clinton Lake on the Wakarusa River. Agriculture is the predominant land use with cropland, grassland, and woodland accounting for about 42, 47, and 7 percent of the basin, separately (Land Cover ).

Image: USGS Kansas Water Science Center


Climate within the KLR is generally classified as humid continental. Summers are relatively hot and humid, while winters are cold. Average annual temperatures increase slightly from approximately 12 degrees celsius (54 degrees Fahrenheit) in the west to 13 degrees celsius (56 degrees Fahrenheit) in the east. Average annual precipitation show a much more definite trend with approximately 71 centimeters (28 inches) in the western portion and 102 centimeters (40 inches) in the eastern portion. Most of the precipitation within the basin occurs during the spring and early summer months (Kansas Water Office).


Ground water within the basin is found in three main aquifers; The Dakota Aquifer is found within the western regions of the basin; The Glacial Drift Aquifer is found within the northern portions of the Kansas River; and The Alluvial Aquifer sits within valleys of the Kansas, Republican, and Blue River (Kansas Water Office).

Water Use

Residential water use within the basin generally comes from surface waters, however groundwater is a major source of water use as well. Approximately 45 percent of water taken from the basin is used for irrigation. Municipal water use takes approximately 39 percent. Much of the remaining percentages of water taken from the basin is used for industrial purposes (Kansas Water Office).

Image: Kansas Water Office


The geologic properties of the KLR basin are generally characterized by the exposure of limestone, shale, and sandstone. There is a trend of progressively younger rocks being exposed from the east to west. Unconsolidated glacial deposits are commonly found in the region of the basin (Kansas Water Office). Five major physiographic regions are found within the KLR basin. Listed in general from west to east are the Chalk Buttes, Blue Hills, Smoky Hills, Flint Hills, and Glaciated Region (Aber and Aber, 2009).

The Chalk Buttes region is found furthest to the west in the basin. This region is characterized by the Niobrara Chalk that formed in the inland seas of the Upper Cretaceous. Surface sediments in the region generally consist of alluvium within valleys, and loess in the upper regions (Aber and Aber, 2009).

The Blue Hills region is found to the east of the Chalk Buttes region. Underlay of this region is generally Upper Cretaceous shale, chalky shale, and chalky limestone. One characteristic feature of the region is the Greenhorn Limestone that was famously used for fence posts and buildings during the turn of the twentieth century. Alluvium is sometimes found as a surface layer in this region (Aber and Aber, 2009).

The Smoky Hills region is found to the east of the Blue Hills. This region is generally similar to the previous two regions, however the Upper Cretaceous layer is often made of sandstone. These layers were deposited in shallow coastal environments near the shore of the inland sea. Dakota sandstone is the most widespread Cretaceous formation in the region. Alluvium is found within valleys of this region, while gravel is common within the uplands (Aber and Aber, 2009).

The Flint Hills region is found to the southeast of the Smoky Hills. This region is characterized by high relief caused by repeating layers of Lower Permian Limestone and shale. These repeating layers allow for strata that are very resistant to the processes of erosion. Alluvium is found within the valleys of this region (Aber and Aber, 2009).

The Glaciated Region is found to the northeast of the Flint Hills Region. Bedrock of the region is Lower Permian in the west, and Upper Pennsylvanian toward the east. Surface sediments within the region include glacial till, loess, and alluvium. Due to the nature of the sediment, this region has great agricultural value (Aber and Aber, 2009).

Image: Water and Drought Portal

The above picture shows chemical application on the KLR which is a form of wetland management. Proper management is needed for nutrient rich soil in which to grow crops, lessened effects from drought, economic stability, and sustainable water resources.


From the Kansas-Nebraska border to the River Gauging Station Center at Clay, KS, the Republican River has eroded a valley of alluvial sand and gravel deposits 18 meters (60 feet) in depth. The average width of this valley is less than 3 kilometers (2 miles) wide, and sits 30 to 60 meters (100 to 200 feet) below the adjacent uplands. The river runs through the Smoky Hills physiographic region of Kansas. The surrounding loess prairie plains have been eroded and now form long tongues of rolling uplands. These upland areas contain entrenched tributaries which drain into the Lower Republican River at nearly right angles. This region is considered subhumid and precipitation is poorly distributed and considered insufficient for optimum plant growth - vegetation growth that would anchor the sediment and allow for less destructive erosion by the Republican River in steep valley areas. (U.S. Bureau of Reclamation). Vegetation is sparse along the immediate river valley, however, mixed prairie grass thrives as you move upland. Fertile alluvial soils in lower elevations with sufficient room for flood plains can support irrigation for crops. A 1968 study revealed that several tree species propagated in alluvium soil that was exposed above the water level for at least two years, in riparian areas of the Republican River in Clay County, KS. These tree species included Sandbar Willow, Almendorf Willow, and Cottonwood, however, none of the species fully matured into a full forest ( Bellah and Hulbert, 1974 ). Several species of water fowl are present through the area, which include a variety of ducks, geese, shorebirds, and various other migratory species that migrate in late summer. Greater prairie chickens and black tailed prairie dogs will also make their homes in riparian areas along the river basin.


General Issues

Several priority issues have been identified within the KLR basin. The first of which is to achieve and maintain sustainable yield of waters outside of the High Plains Aquifer regions. Several agencies are currently working to set water management criteria to ensure long term use (Kansas Water Office).

Water Conservation is another priority issue within the KLR basin. Initiatives are currently being implemented to preserve and protect water that is used for irrigation, municipal, and industry. As of 2006, 132 of the 190 public water suppliers within the basin have developed water conservation plans. Conservation plans typically address drought issues and focus on controlling the cost of water use (Kansas Water Office).

Droughts and floods are among the issues currently being addressed. The National Flood Insurance Program (NFIP) is currently being utilized in the basin to address flooding issues. This program assists with the construction of watershed dams to control flooding. Public water supply is especially of concern to drought vulnerable water supplies. Water supply goals of these initiatives within the basin are focused on reducing the water supplies that are vulnerable to drought conditions. This is often achieved by providing technical, technical, financial, and managerial capabilities of water suppliers (Kansas Water Office).

Water quality concerns within the KLR basin include bacterial, Oxygen demand, metals, Volatile Organic Compounds (VOC's), pesticides, and sedimentation. Several initiatives are currently working on reducing contaminants. Source water protection plans have been put in place by many water agencies to address these issues. Financial and technical support is also being provided to landowners. Many initiatives have included Best Management Practices (BMPs) and educational opportunities for farmers and landowners. The BMPs set guidelines for farmers and consultants who planned on using herbicides. Such guidelines included; No application of herbicides after a specified date; Herbicide application into soil; Creating buffer zones near water sources (Kansas Water Office).

Mission Lake

Mission Lake is located near the city of Horton, in Brown County, Kansas. The lake was constructed in 1924 by damming Mission Creek which is a small tributary within the Delaware River subbasin, and the intent was to create a raw water source for public consumption and recreation. Unfortunately, over the decades, sediment has filled the reservoir and the availability of public drinking water has significantly decreased. Today, the city now relies on underground wells to serve the cities of Horton and Willis. The reservoir is still used for recreational purposes (Mission Lake Restoration Project).

Image of Mission Lake: Mission Lake Restoration Project

Dredge Equipment at Mission Lake. Image: Mission Lake Restoration Project

Discharge from Mission Lake. Image: Mission Lake Restoration Project

In 2010, the city of Horton began participating in a pilot project under the Water Supply Restoration Program administered by the State Conservation Commission. Under this program, the city receives financial assistance for the restoration of Mission Lake. The project includes the removal of 570,000 cubic meters (750,000 cubic yards) of sediment and the construction of a Confined Disposal Facility that is located within a tributary to Mission Creek. Dredging occurred at a rate of approximately 34,000 liters (9,000 gallons) per minute and about 20% of the dredge material was solid sediment (Kansas Water Office). In August of 2010, the dredging was complete: more than 760,000 cubic meters (1,000,000 cubic yards) of sediment was removed and 760,000 cubic meters (620 acre feet) of water was restored. Dredge America and KBS conducted bathymetric surveys to ensure that the contracted amount of sediment had been removed from the lake (Kansas Water Office). The city of Horton is currently working with the Delaware Watershed Restoration and Protection Strategy team to implement management practices which will address surface and streambank erosion, limit future erosion, and subsequent sediment deposits into Mission Lake (Mission Lake Restoration Project).

Image: Kansas Water Office

Horseshoe Creek

The Horseshoe Creek Watershed lies within the Lower Republican River Basin Watershed and is located in Marshall and Washington Counties in Kansas and Gage County in Nebraska. This watershed spans over 105.5 square miles. This is a predominantly rural area with about 99.7% of the land being used for agricultural and crop purposes. Additionally, there is grassland and woodland cover (Pritchard and Wedel, 1998).

Horseshoe Creek has also been host to several archeological findings. Lithified bison fragments have been found in the watershed. These fragments are surrounded by fire-scarred rocks which may indicate the presence of an early archaic period hearth. The proposed hearth may be 6,000 to 9,000 years old (Pritchard and Wedel, 1998).

Damage to agriculture from floods has been a recurring problem in the watershed and in 1995, the Kansas Water Authority formed an organized watershed district to develop solutions to the flooding problems and address numerous other water quality issues. Watershed districts have historically focused on flooding and damming issues, however, the efforts in the Horseshoe Creek area are focused on the big picture: flooding, water quality protection, and riparian management have all been addressed (Pritchard and Wedel, 1998).

Eight critical steps were identified in the planning and management plan for the Horseshoe Creek watershed area:

1. Determine the existing riparian-wetland and watershed condition.

2. Determine Potential Natural Condition (PNC) by using relic areas, historic photos, etc.

3. Determine the minumum conditions required for the area to function properly

4. Determine existing and potential resource values and the plant communities necessary to support these values.

5. Negotiate specific objectives to reach management goals for the watershed

6. Design management actions to achieve goals.

7. Design appropriate monitoring strategies to assess progress towards meeting goals.

8. Maintain management flexibility to accommodate change based upon monitoring results.

Table Created By Marco Allain

The Horseshoe creek watershed restoration project has had the effect of decreasing discharge, measured in cubic feet per second (cfs), of local streams and distributaries. The physical implementation of the project began to affect local hydrology after 1999. The table above exemplifies the moderating effect of the restoration process on discharge. The rows on the right ask whether current discharge levels are higher over a 73 year period for each given variable. The row to the right says either yes or no and how many out of five measured stations the yes or no applies to. The data comes from Big Blue River at Barneston, Nebraska; Big Blue River at Marsyille, Kansas; Lake Blue River NR Barnes, Kansas; Mill C at Washington, Kansas; and Little Blue River at Hollenberg, Kansas (Pritchard and Wedel, 1998).

Runoff: Various Locations

Runoff has been a major concern for environmental management. According to Dunne et al, the subbasins with relatively high potential runoff are located in the central part of the Lower Republican River Basin. These subbasins are Black Vermillion River, Clarks Creek, Delaware River upstream from Muscotah, Grasshopper Creek, Mill Creek (Wabaunsee County), Soldier Creek, Vermillion Creek (Pottawatomie County), and Wildcat Creek. The subbasins with relatively low potential runoff are located in the western one-third of the river basin (Dunne et. al. 1975).

Runoff facilitates pollutants such as coliform bacteria, atrazine and suspended sediment. These are the pollutants of primary concern in the Kansas-Lower Republican (KLR) basin. Three areas in the basin contribute the majority of the contaminants. These areas are the Big and Little Blue River subbasins, the Delaware subbasin and the Kansas River Corridor. Black Vermillion and Grasshopper Creek are also target watersheds for environmental enhancements. Environmental management in the KLR is based on returning a site to its potential natural condition or maintaining a site in proper functioning condition. Relic streams and wetland sites are also of significant importance (Dunne et. al. 1975).

Glacial Hills Resource and Conservation District

The Glacial Hills Research and Conservation District is located along the Delaware River watershed in Northeastern Kansas. This watershed is a tributary within the Lower Republican River Basin and spans Atchison, Jefferson, and Jackson Counties. In 2009, the Delaware River Watershed Restoration and Protection Strategy (WRAPS) initiated a project in conjunction with the Glacial Hills Resource and Conservation District to reduce high streambank erosion rates, loss of farmland, and to limit the amount of sediment entering Perry Federal Reservoir (Wild Horse River Works).

Delaware River Stabilization Efforts. Image: Delaware River WRAPS

To eliminate streambank erosion, combinations of Longitudinal Peaked Stone Toe Protection and rock veins or bendway wires were installed along various sites to reduce streambank erosion. These procedures re-directed flow away from the eroding river banks, which in turn, reduced water velocity and shear stress in the near bank region. The streams width was reduced and the deepest part of the stream's channel moved toward the center of the stream. These efforts moved the streams to a more naturally stable condition. After the rock structures were in place, and stream flow was altered, construction began to convert the streambanks to a minimum 2h: 1v slope. The streambanks were then seeded with native wildgrass mixtures and some native tree and shrub species. 11,675 bare root seedlings and 3,378 live cutting were planted on the streambanks. This project was successful in reducing streambank erosion, improving stream function, and restoring riparian habitats (Wild Horse River Works).


The Kansas - Lower Republican River Basin in northeastern Kansas is a vast area with a dynamic geologic and human-use history. Limestone, shale, and sandstone are exposed throughout the region and glaciers have left their mark with surface sediment, alluvium, and till which impact current water flow. Water conservation, droughts, floods, and water quality are areas of concern according to the Kansas Water Office. These issues have been addressed and several solutions have been implemented, specifically at Mission Lake, Horseshoe Creek, and the Glacial Hills Resource and Conservation District on the Delaware River. With proper environmental management practices and constant monitoring, the Lower Republican River Basin will continue to thrive and support native vegetative species and wildlife, while allowing for non-invasive human-use activities.


Wetland Environments: Emporia State University Molly Reardon, Marco Allain, Kyle Jackson (2012).