thumbnail

Effects of agricultural and residential land use on ground-water quality, Anoka Sand Plain Aquifer, east-central Minnesota

Water-Resources Investigations Report 93-4074

Prepared In cooperation with the Minnesota Department of Natural Resources, Division of Waters and the Soil and Water Conservation Districts of Anoka, Chisago, Isanti, Sherburne, and Stearns Counties
By:

Links

Abstract

Water quality in the 1,700-square-mile Anoka Sand Plain aquifer is affected by irrigated and nonirrigated agriculture and by residential land use. Concentrations of sulfate, chloride, nitrite plus nitrate nitrogen, and pesticides in ground water are related to human activities; nitrite plus nitrate nitrogen concentrations are affected more than concentrations of other chemical constituents. Of the water samples collected from 100 wells during this study, samples from 30 wells had concentrations of nitrite plus nitrate nitrogen greater than 10 mg/L (milligrams per liter), which is the limit recommended for drinking water by the Minnesota Pollution Control Agency. Analysis of 360 water samples indicated that the median concentrations of nitrite plus nitrate nitrogen for undeveloped, nonirrigated-cultivated, irrigated, and residential lands were 0.22,2.0,5.3, and 4.2 mg/L, respectively.

Differences in nitrite plus nitrate nitrogen concentrations at various depths below the water table were statistically significant. Median concentrations of nitrite plus nitrate nitrogen in groundwater samples less than 10 feet, 10 to 20 feet, and more than 20 feet below the water table were 5.1 mg/L, 2.7 mg/L, and less than 0.1 mg/L, respectively.

Seasonal fluctuations in nitrite plus nitrate nitrogen concentrations at many wells were as great or greater than long-term change; however, the springtime median concentration of nitrite plus nitrate nitrogen increased steadily from 1984 (4.8 mg/L) through 1987 (5.5 mg/L).

Triazine herbicides were detected in 11 of 18 samples analyzed for pesticides. Concentrations of atrazine were less than the 3 (J-g/L maximum contaminant level set for atrazine by the Minnesota Department of Health and by the U.S. Environmental Protection Agency.

Study Area

Additional publication details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Effects of agricultural and residential land use on ground-water quality, Anoka Sand Plain Aquifer, east-central Minnesota
Series title:
Water-Resources Investigations Report
Series number:
93-4074
Year Published:
1993
Language:
English
Publisher:
U.S. Geological Survey
Publisher location:
Mounds View, MN
Contributing office(s):
Minnesota Water Science Center
Description:
vi, 62 p.
Country:
United States
State:
Minnesota
Other Geospatial:
Anoka Sand Plain aquifer
Online Only (Y/N):
N
Additional Online Files (Y/N):
N