Watershed Studies

The 694,400-acre St. Joseph River watershed is in northeast Indiana, northwest Ohio, and south-central Michigan. Indiana occupies 56% of the watershed, while Michigan and Ohio each occupy 22%.

With its headwaters in Hillsdale County, Michigan, the St. Joseph River flows southwest through Williams County, Ohio; Defiance County, Ohio; DeKalb County, Indiana; and Allen County, Indiana, before converging with the St. Mary's River in Fort Wayne, Indiana to form the Maumee River in the Western Lake Erie Basin. Both Noble County and Steuben County in Indiana contribute water to the St. Joseph River, through the Cedar Creek and Fish Creek tributaries.

The watershed is primarily agricultural, with approximately 64% in cropland and 15% in pasture or forage. Woodlands and wetlands are found in 10%, while the remaining 11% consist of urban, farmsteads, airports, golf courses, and other land uses.

The majority of the St. Joseph River Watershed is rural, with a population of approximately 65,000 (excluding Ft. Wayne). Fort Wayne is the largest city in the watershed with over 200,000 residents. Auburn, Indiana is the second largest city and Montpelier, Ohio is the third largest. The population is increasing throughout the watershed, especially in southern DeKalb and Noble Counties and northern Allen County. Small 5–10-acre parcels are numerous in these areas. In all three states, industry is claiming areas along the interstate and major state highways.

The topography of the watershed varies from rolling hills in Hillsdale, Williams, Noble, and Steuben Counties to nearly level plains in DeKalb and Allen Counties. The St. Joseph River follows the Fort Wayne moraine and flows past numerous low bluffs and terraces. This indicates that the river was once much wider and deeper. Much of the St. Joseph Riverbed is composed of sand and gravel deposits. The average slope of the river's bottom is 1.6 feet per mile.

Soils in the watershed were formed from compacted glacial till. The predominant soil textures are silt loam, silty clay loam, and clay loam. Soil associations include Mini-Morley, Morley-Glynwood-Blount, and Blount-Pewamo. Erosion and over-saturation are the major soil limitations.

The St. Joseph River serves as the drinking water supply for the 200,000 people of Fort Wayne and New Haven. Fort Wayne's Three Rivers Filtration Plant processes 34 million gallons of water daily from the St. Joseph River. The filtration plant also operates two large reservoirs: Cedarville Reservoir in the St. Joseph River and Hurshtown Reservoir. Together these reservoirs store over 1 billion gallons of water.

The Initiative has been involved in watershed planning for the entire St. Joseph River as well as its sub-watersheds. We have organized stakeholders and produced watershed management plans for Upper and Lower Cedar Creek, as well as the Lower St. Joseph and Bear Creek sub-watersheds.

A watershed management plan (WMP) is like a map to show you where you are going. To create a map, you need to know your territory and have some sense of where you’ve been, and where you want to go. Planning involves input and involvement from the various stakeholders of the watershed, from experts to novices: landowners, land users, businesses, industry, institutions, and government agencies – in short, everyone who lives, works in, or uses the watershed.

Watershed plans guide stakeholders in their efforts to protect, restore, and enjoy the river and its resources. Plans provide benchmarks for the watershed, allowing us to understand where we are today; communicate our vision to project what we do in the future; and establish our goals, so we can measure our progress.

The Initiative has produced several watershed management plans to date.

the St. Joseph River Watershed Management Plan

Upper St. Joseph River Watershed Management Plan (West Branch, East Branch, Nettle, and Fish Creek)

Middle St. Joseph River Watershed Management Plan

Lower St. Joseph River-Bear Creek Watershed Management Plan

Cedar Creek