Our Water Proof series is all about coordinating both urban and rural watershed best practices and the need to work together to improve water quality. It will provide a technical transfer of information and the tools to enable active participation to preserve, protect and restore the watershed. Methods will include, but not be limited to, low impact development, green infrastructure, riparian buffer enhancements, installation of conservation areas such as greenways and rain gardens, stream cleanups and stream teams, expansion of the Clean Water Raingers Club.
That’s a mighty goal, but one that it necessary in light of the rapid growth and ever changing land use of in NW Arkansas and NE Oklahoma.
The Illinois River
The Illinois River Watershed covers 1.1 million acres with 484,947 acres /758 square miles in northwest Arkansas. This upper Arkansas portion has designated uses for the propagation of fish and wildlife, primary and secondary contact recreation, and domestic, agricultural and industrial water supplies. Oklahoma has designated the use of the River in northeast Oklahoma as a state scenic river.
The beginning of the Illinois River, just south of Fayetteville, touches urbanized areas, and flows west through residential neighborhoods, city parks, commercial developments and eventually into rural and agricultural lands along its course to the state line bordering Oklahoma. Land use of the Watershed in northwest Arkansas is approximately 46% pasture, followed closely by 41% forest, 13% urban, and <1% water. The watershed is home to approximately 210,000 Arkansas residents (2010 census). Additionally it was one of the fastest growing metropolitan areas in the state and the United States from 2000 to 2010.
NPS Priority Watershed Map
(Illinois River Watershed defined in gold)
Over the last decade, pasturelands have reduced in area from 64% to 46% as a result of pastures being converted into urban development or restored to forested lands. The amount of urbanized areas has more than doubled, with the majority of the growth in the last seven years. The forested areas have increased from 29% to 41% over the past decade because of an increase in designated forests and herbaceous vegetation, shrubs and other woody plants. These changes, from 1992 to 2006, show the dynamic nature of watershed land use. Watershed management strategies must be adaptive to landscape dynamics, because changes in land use and land cover may alter the selection of appropriate management strategies to address water quality concerns.
The Osage River
There are about 1,100 miles of streams in the upper Illinois River Watershed, and approximately 103 miles of impaired streams, or about 10%, of the total number of stream miles. About 91 stream miles are impaired by pathogens, 4 stream miles impaired by sediment, and 8 stream miles impaired by nitrate.
There have been a number of studies that prioritized streams or sub-basins in the watershed for water quality improvement. These studies each used a different approach for prioritization. The IRWP Watershed Management Plan summarizes the significant studies and compares their results.
Summary of recommended Best Management Practices for the Illinois River Watershed
Land use changes are projected to be significant. The incorporated municipalities combined cover approximately 22% of the watershed area, while urban land use currently accounts for 13%. The towns and cities, however, have designated planning areas, defining the potential extent of future annexation and municipal service extensions which will constitute almost 58% of the total watershed area, approximately tripling the current incorporated area within the Watershed. Practices such as Low Impact Development and Green Infrastructure will be implemented and should be used to address increased impervious surfaces and stormwater runoff in planning strategies.
These urban management challenges are critical areas to be addressed with some of the greatest opportunity for positive impacts and water quality improvements in the watershed. These are also tremendous opportunities to continue to build on the region’s history of working together to solve common problems.
In May 2007, the Illinois River Watershed Partnership began the process of developing a comprehensive Watershed Management Plan following U.S. EPA watershed planning elements for the upper Illinois River Watershed in Arkansas. Our goal was a comprehensive watershed-based management plan that provided information to generate options for management approaches and practices that address conditions believed to impair, degrade, or threaten water quality in the upper Illinois River Watershed.
But none of it is possible without the support and participation from landowners, municipalities, counties, industries, and landowners. Developing a stakeholder-driven watershed management plan for a watershed as large and diverse as the Upper Illinois River Watershed is a difficult process. That’s why an established watershed partnership that is diverse in nature is essential. Leadership, communication, a shared vision and commitment are essential to the process of working together through voluntary practices to achieve success!