For immediate release November 10, 2004
Prepared by Nancy Tilt for the Ontario Soil and Crop Improvement Association
Take a paved livestock yard. Perch it on a hill with a stream running through
the valley below. Add some rain. And watch the run-off from the yard make its
way down the lane side ditch, eventually reaching the stream.
That was the situation at Darrin Partridge's Northumberland County beef farm,
and one that he wasn't too happy about. Aside from the obvious environmental
concerns, Partridge also runs a pheasant hunting preserve, and the image wasn't
one he wanted as guests arrived at his farm.
Enter the Ministry of Natural Resources' Northumberland Stewardship with an
innovative approach for treating livestock yard runoff—and some funding support.
The rest reads a bit like the story of Midas, turning manure effluent into a
golden liquid suitable for dispersal on a pasture field that doubles as a filter
strip.
Northumberland Stewardship Coordinator, Glenn McLeod, and council members
introduced Partridge to the idea of a vegetative filter strip (VFS)—a relatively
low cost, environmentally sound treatment system designed to handle run-off from
solid manure storages and outdoor livestock yards.
Vegetative filter strips are not storage systems although there is a storage
component built into the design that is sufficient to handle a storm event for
the specific region of the Province. The 240 days storage requirement under the
Nutrient Management Act does not apply.
A low concrete wall along the edge of Partridge's livestock yard retains solid
material, and controls the rate of run-off through openings in the wall. These
lead down a concrete chute to a secondary containment area part way down the
slope.
A second concrete wall constructed along the down slope edge of this area stops
any additional solid material. An opening in this wall houses a concrete box
with metal screens that further restrict solid material and control the rate of
run-off flowing into a 2000-gallon concrete holding tank. Partridge removes
solid material from the containment area and yard for later spreading.
When the holding tank is full, a float mechanism triggers a 1 hp sewage pump
that pumps the liquid into a 1½ inch black plastic pipe. This pipe runs to a
116-ft. 6-inch PVC sewer pipe at the upper edge of an adjacent 150-ft long
sloped pasture area, which acts as the filter strip.
Strapped to a wooden frame and plugged at both ends, the PVC pipe has ¾-in holes
drilled every 31 inches. The spreader pipe is set level to spread the effluent
evenly across the top end of the filter strip as it drains. With the spreader
pipe at a higher elevation than the sewage pump, any residual liquid in the
supply pipe flows back to the holding tank when the pump shuts down.
The design of the yard storage outflow, pump and pipe size are based on factors
that determine the vegetative filter strip’s ability to receive the run-off,
such as slope, vegetative cover and soil type. More porous soils, such as sandy
loam, can accept runoff at a much faster rate than fine texture soils, such as
clay, resulting in a smaller area required for the VFS.
Northumberland Stewardship obtained funding for the project through Agriculture
and Agri-Food Canada's Agricultural Environmental Stewardship Initiative (AESI),
as well as contributing funds of its own. AESI is administered through the
Agricultural Adaptation Council (AAC) and the Ontario Farm Environmental
Coalition. The Ontario Soil and Crop Improvement Association is reporting on the
project on behalf of AAC.
Eligibility for funding required an approved Environmental Farm Plan as well as
financial input from the landowner. Costs will vary depending on site and amount
of work required. Partridge contributed about 50% of the cost through in-kind
labour, materials and funds. Typically costs of VFS systems are in the range of
$10–15,000. Engineering is an important component in the design of VFS systems,
and local OMAF Engineer, Bob Stone, provided this support.
Northumberland Stewardship reviewed 14 applications from producers to
participate in this demonstration site. Stewardship Chair Joe Banbury notes, "An
added benefit of this project has been an increased awareness of environmental
issues, and a number of personal projects to address other environmental
concerns."
The first "tripping of the switch" occurred this past August as representatives
from several local agricultural organizations eagerly watched.
Flat concrete patio stones positioned under each hole in the spreader pipe help
prevent erosion. As the holding tank drained, the effluent trickled off the
stones into the freshly clipped pasture. It took about 20 minutes for the
holding tank to empty, and in that time, the liquid had moved about 20 feet down
the strip and soaked into the soil.
Pasturing and/or harvesting a hay crop are management options for the filter
strip. It's important, however, to maintain at least 4–5 inches of vegetation.
This is essential in retarding the effluent flow, especially during frozen
ground conditions. Under snow conditions the effluent flows under the snow and
freezes, soaking in when the ground later thaws. There are few rainfall/runoff
events during the winter season.
"People can be skeptical of trying something new, especially when some cost is
involved," Partridge notes, "but I'm more than pleased with this as a solution
to my problem."
Vegetative filter strips are an acceptable method of handling run-off under the
Nutrient Management Act (NMA). However, MOE approval is currently required
before they can be legally installed. Work is underway to bring VFSs under the
umbrella of the NMA.
Five VFSs were constructed over past years across the province on behalf of the
Ontario Cattlemen's Association under the Canada-Ontario Agriculture Green Plan.
Monitoring for nitrates, ammonia, P, K, total dissolved solids, faecal coliform
and BOD has shown no accumulation of nutrients in the soil profile and no change
in groundwater samples from pre-construction levels.–30–
For more information or photos of the project contact
Glenn McLeod, Northumberland Stewardship;
Tel: 705-755-3298 or e-mail:
glenn.mcleod@mnr.gov.on.ca OR
Andrew Graham, Ontario Soil and Crop Improvement Association; Tel:
519-826-4214
or e-mail: oscia@ontariosoilcrop.org
OR
Nadine Buitenhuis, Agricultural Adaptation Council, Guelph; Tel: 519-822-7554
or
Nadine's e-mail
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