Nineteen watersheds are identified within the Nemaha basin:
Brownell, Ziegler Creek, Rock Creek, Winnebago-Bean, Spring Creek, South Fork, Wilson Creek, Long Branch, Upper Big Nemaha, South Branch, Middle Big Nemaha, Upper Little Nemaha, Turkey Creek, Big Muddy, Peru-Brownville, Squaw Camp Creek, Lower Little Nemaha, Lower Big Nemaha, South Fork Tributaries.
More than 400 flood or erosion control dams and structures built by the NRD or with NRD assistance are spread throughout the District. Most of the structures include NRD responsibility for inspection and maintenance. With the exception of the four (soon to be five) public recreation lakes operated by the NRD, all other watershed structures are privately owned.
Access for fishing or hunting is not required and only available upon permission and consent of the landowner.
Nine structures are classified as “high hazard” because of their potential for loss of life and property in the event of a failure. These structures, listed below, are inspected every year by both the NRD staff and Nebraska Department of Natural Resources. In the unlikely event of a failure, detailed emergency action plans are in place for each location.
- Wilson Creek 8-H (east of Syracuse, Otoe County-impacts Highway 2)
- Wilson Creek 2-N (south of Otoe, Otoe County)
- Upper Little Nemaha 21 (southwest of Bennet, Lancaster County)
- Upper Little Nemaha 23 (south of Bennet, Lancaster County)
- Upper Big Nemaha 7-A (southwest of Adams, Gage County)
- Upper Big Nemaha 11-A (east of Firth, Lancaster County)
- Upper Big Nemaha 25-C (southwest of Adams, Gage County-impacts Highway 41 & Burlington Northern Railroad)
- Middle Big Nemaha 96 (north of Tecumseh, Johnson County)
- Long Branch 21 (northwest of Humboldt, Richardson County)