County governments assume responsibility for carrying out certain state policies. In most cases, county governments enforce the state’s erosion control policy under the Michigan Soil Erosion and Sedimentation Control Act 347 (1972), and Part 91 of Act 504 (2000). County road commissions typically are self-regulating in terms of erosion control, and local municipal governments may also administer this program.

The County Drain Commissioner’s Office is responsible for the operation and maintenance of stormwater management systems, also known as “county drains.” A watershed’s designated county drains may be open ditches, surface streams, underground pipes, retention ponds, or swales that convey stormwater. These systems are designed to provide stormwater management, drainage, flood prevention, and stream protection for urban and agricultural lands. The Drain Code gives the Drain Commissioner the authority to construct and maintain drains, creeks, rivers, watercourses, and their branches for flood control and water management. Drains that are not designated as county drains are maintained by the County Road Commission. These include roadside ditches, pipes, and culverts that pass under state highways and county roads.

In addition to oversight for drains, the County Drain Commissioner must maintain the established levels of lakes throughout the watershed. Under the 1961 Inland Lake Level Act (Act 146), the Drain Commissioner is responsible for having all lake-level control structures on inland lakes inspected every three years by a professional engineer. The Drain Commissioner is also responsible for assessing the costs of establishing and maintaining lake levels, and for filing petitions in circuit court to create a “special assessment district” to pay those costs.