Constructed Wetlands Help Protect Water Sources

Source: Saskatchewan Agriculture and Food

Increasing environmental concern has generated a greater focus on water quality across Canada, and many industries are making an effort to better protect water sources.

The livestock industry is a vital part of the Saskatchewan economy, and Jared Ward, an Environmental Engineer with Saskatchewan Agriculture and Food (SAF), says the sector is likewise taking a leading role in safeguarding water sources. One approach that is gaining interest is the "constructed wetland" concept.

"Rainfall and snowmelt draining from livestock facilities can pick up manure, bacteria and nutrients, which can potentially end up in downstream water bodies, streams and groundwater sources," Ward said. "Constructed wetlands can offer an effective and low-maintenance option for the treatment of this runoff water."

A constructed wetland is a shallow, earthen basin planted with rooted, emergent wetland vegetation. It can clean and purify wastewater by incorporating microbes, fungi, algae and wetland plants that either reduce or transform pollutants.

Constructed wetland technology has become an established treatment method for municipal and livestock wastewater in many provinces in Canada. Ward says Saskatchewan has gained experience using this type of technology in the municipal waste industry.

"One example is the SaskPower constructed wetland built in 1994 near the City of Estevan," he noted. "This wetland purifies the city's secondary sewage wastewater, eliminating the semi-annual release of the lagoons to the environment. It also provides marsh habitat for a variety of wildlife."

Hoping to duplicate the successes achieved in the management of municipal wastewater, SAF, in conjunction with Agriculture and Agri-Food Canada (AAFC), is developing a pilot constructed wetland project for the treatment of livestock waste. The project will provide valuable information on the design and operation of wetlands for Saskatchewan's livestock sector.

"We're very optimistic that constructed wetlands can offer a cost-effective treatment of livestock runoff water," said Serena McIver, an Environmental Engineer with AAFC. "They've been shown to reduce nutrients and suspended solids, bacteria, viruses and heavy metals by 70 to 90 per cent."

McIver says constructed wetlands have the potential to deliver many benefits, including nutrient reduction, odour control, water quality improvement, wildlife enhancement and aesthetic improvement. They can also provide economic benefits by reducing maintenance and labour costs, and decreasing the required land application area.

Costs associated with constructing a wetland depend on a number of factors, most importantly the volume of water to be treated and its initial quality.

For more information, contact:
Jared Ward, Environmental Engineer
Saskatchewan Agriculture and Food
Phone: (306) 787-4692
E-mail: jward@agr.gov.sk.ca

Serena McIver, Environmental Engineer
Agriculture and Agri-Food Canada
Phone: (306) 780-5152
E-mail: mcivers@agr.gc.ca