Passive Filtration for Cattle Runoff
Willow Creek Sub-District
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Characteristics
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Benefits
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Project Overview
Background:
Cattle are commonly overwintered in confined pens, and during spring melt, runoff from these areas can transport large amounts of nutrient laden sediment through municipal drainage systems that ultimately feed into Lake Winnipeg.
This runoff may also contain elevated levels of bacteria such as fecal coliform. Overland flooding of well heads or watering ponds during spring melt can cause contamination of drinking water. High spring runoff can also cause significant erosion of municipal drains and ditches as vegetation has not yet re-established yet at this time of year. Common strategies to reduce nutrient loading include vegetated buffer strips, and grazing annual lands, through bale grazing, stubble grazing, swath grazing, etc.
The property occupies a total of 65 ha; consisting of 50 ha of crop land and pasture, 6 hectares of deciduous forest, and a 9-hectare yard site which includes the 0.55-hectare wintering site. Historically, manure from the wintering pens was scraped regularly and piled south of the pens; runoff from this pile drained freely and likely flowed into the slough on the property.
Spring melt typically contains higher concentrations of contaminants because over the winter manure accumulates in layers and is compacted into the snow throughout the winter. Due to cold temperatures of the winter, this results in a large amount of particulate matter buildup that does not decompose. When temperatures rise, and during spring melt the material is rapidly mobilized and washed away in a short time resulting in higher concentrations of contaminants.
Project Objectives:
The goal of the project was to develop a runoff management system modelled after the passive filter installed by the Village of Dunnottar at their Wastewater Treatment Lagoon in 2015. The system was designed to mimic the biological and physical processes of natural systems with the goal to reduce eutrophication, contamination and erosion protentional. The project was designed with the goal to reduce sediment, harmful bacteria, and nutrients in the runoff, reduce runoff intensity to minimize erosion and recycle/recover nutrients for beneficial reuse.
Project Features:
This Passive Filtration for Cattle Runoff project included regrading the cattle overwintering pen to direct runoff into a newly constructed retention pond; constructing this small retention pond, supplying and installing a manhole lift station; building a granular passive filter, and completing general site improvements. The system consists of an approximately 150m2 passive filter and a 670m2 settling pond.
Project Timeline:
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