ST. PAUL — Changes in water and land management are needed across the Minnesota River Basin to improve water quality in the state’s namesake river, as well as streams and lakes throughout the 10 million acres of the basin.

Four studies by the Minnesota Pollution Control Agency and local partners, funded by the Legacy Amendment, determined the total maximum daily load or the maximum amount of a pollutant that a water body can accept and still meet water quality standards. The standards are designed to make sure waters are safe for fishing and swimming.

One study concerns the major portion of the Minnesota River, focusing on total suspended solids or sediment and other particles that cloud the water. The study calls for decreasing sediment in the river by 50%. Too much water draining at too fast a rate erodes soil from land as well as streambanks, bluffs and ravines, muddying the water. The muddy water then makes it hard for fish and other aquatic species to breathe, find food and reproduce.

The sediment is also filling in the Lower Minnesota River and even Lake Pepin downstream at a much faster rate than before European settlement — and intensive farming — of the basin.