Potential for groundwater recharge seepage from flood-retarding reservoirs in south central Nebraska

ABSTRACT:

Seepage rates at two flood-retarding reservoirs in Nebraska's Upper Blue River Basin were monitored for three years to determine what potential might exist for increasing groundwater recharge. Average seepage rate for the two reservoirs, each with a watershed of about 1,000 acres (405 hectares), was 0.50 inch per day (1.27 centimeters/day) at the Clay County site and 0.59 inch per day (1.50 centimeters/day) at the York County site. This amounts to an annual average seepage volume of 53 and 92 acre-feet per year (65,000 and 110,000 cubic meters) at the Clay and York County sites, respectively. Seepage from these reservoirs potentially increases groundwater recharge by an amount equal to the volume seepage after the overburden on the aquifer is sufficiently wetted to allow additional seepage to reach the aquifer. Reservoirs therefore might be used in conjunction vnth other water conservation practices to reduce the groundwater overdraft in the Blue River Basin of Nebraska.