Measurement of Leakage from Earthen Manure Structures in Iowa

eakage from a representative sample of 28 earthen manure storage structures and lagoons (selected from 459 built in Iowa between 1 January 1987 and 31 December 1994) was determined using a water–balance approach. Forty–three percent (43%) of tested structures had leakage rates significantly (p \u3c 0.05) lower than the regulatory limit of 1.6 mm/d (1/16 in/d) specified by the State of Iowa at the time the basins were constructed. Leakage from 53% of the structures was too close to the regulatory limit to be categorized as being significantly above or below it. One structure (4%) exhibited leakage significantly greater than the regulatory limit. Regression analysis indicates a slight, but statistically significant, decline in leakage rate with increasing structure age. Structures constructed in glacial till showed significantly lower leakage rates than those constructed in sand and gravel, colluvium, or loess. Comparison of slurry pits and lagoons showed no significant difference in leakage rate

Fate and Transport of Nutrients in an Iowa Agricultural Watershed

Transport of nitrogen (N) and phosphorus (P) in various forms to water resources can cause water quality concerns relative to drinking water and aquatic life that has to live in those waters receiving agricultural drainage. Of particular concern is the fate of nutrients applied as fertilizer and/or animal manures, and their potential transport with runoff water, eroded soil/sediment, and leaching water. In order to reduce or control nutrient transport/losses, an understanding of the factors that affect losses (chemical, hydrologic, and management) is needed. An ongoing monitoring study of the Upper Maquoketa River in northeast Iowa is providing watershed-scale information on nutrient fate and transport and is the basis for this paper.</p

Measurement of Leakage from Earthen Manure Structures in Iowa

eakage from a representative sample of 28 earthen manure storage structures and lagoons (selected from 459 built in Iowa between 1 January 1987 and 31 December 1994) was determined using a water–balance approach. Forty–three percent (43%) of tested structures had leakage rates significantly (p This article is from Transactions of the ASABE 44, no. 6 (2001): 1609–1616.</p