BROOKINGS, S.D.(WNAX)- Dairy farms continue to locate and expand along the I-29 corridor in eastern South Dakota. Those facilities are all contained in the Big Sioux River watershed.

Jay Gilbertson, manager of the East Dakota Water Development District based in Brookings, says those large farms aren’t a major source of pollution into the river.

Gilbertson says smaller operations don’t have the same regulatory oversight.

The legislature this year approved three million dollars to improve water quality in the Big Sioux River. Gilbertson says much of that will be focused on protecting the water from the land.

Gilbertson says the improvements will be primarily along the river upstream of Sioux Falls.