Slow sand filters for safe livestock water
Submitted by Jody Holthaus
Meadowlark District Agent
A project this summer to make pond water safe for livestock was the construction of slow sand filters. This technology has been used since the 1890s. It has been used for small municipalities for human drinking water and researched by 18 universities.
A committee of extension folks, some retired, worked on the design of the filters.
The filter is made from easily found supplies, making it easy for a farmer/rancher to reproduce. Chemical totes are used with PVC plumbing, with a layer of gravel, geotextile fabric and then at least 18 inches of sand. Water from the pond is pumped using Solar power, backed up by batteries. The pond water enters the filter through the top. A biofilm forms on the top layer of the sand, that filters out the blue/green algae, ecoli and other toxins. As the filter fills up, water is released through the side valve into a stock tank.
The pump can be put on a timer and a float can be used in the filter to ensure proper water levels. Although, the filters have not been tested extensively, they do show promise of cleaning up the water from questionable farm ponds.
Two slow sand filters have been constructed and are portable, if needed temporarily for an emergency.
This project was funded with a grant from KCARE-Kansas Center for Agricultural Resources and the Environment and the Kansas Center for Sustainable Agriculture and Alternative Crops. Support for the project was given by the Meadowlark Extension District.