The Keffer Marsh complex, located immediately north of Rivermede Rd. and named after one of the original pioneering families to settle in the area, is the highlight of Langstaff EcoPark. Historically this was a wetland site, but it was filled in to create agricultural land when farming was the major economic activity in Vaughan Township. Later the site was chosen as an outflow point for runoff, carried there through underground channels, from over 90 hectares of adjacent industrial land. At the time little concern was given to water quality, but now the old water retention pond has been transformed into a thriving wetland complex, thanks to a partnership between the Vaughan Chamber of Commerce, the TRCA and the City of Vaughan.
The 2-hectare project comprises the marsh itself and a larger deciduous swamp, which is believed to be largest constructed area of its kind in Ontario. As before, water is still supplied to the site though the diversion system from Westminster Creek, a tributary of the West Don that actually merges with the main river south of Steeles Ave. Base flow from the creek is now directed into a settling pond, on through cattail thickets into the marsh, then finally through a porous rock weir into the West Don. This design serves to maximize water quality improvements and diversify wetland habitat. The much greater volumes of water generated during major rain storms are diverted into the swamp, designed to hold 10 million litres of water over a 24-hour period. Here the sediments settle out and cleaner water seeps back into the watercourse. In an average year, the swamp is expected to collect water four to six times.
Many community groups have assisted in replanting the site with aquatic plants, trees and shrubs, but now natural recolonization is rapidly taking over. Green frogs, American toads, turtles, beavers and a wide variety of birds now call Keffer Marsh their home. The area has been completed with nature trails, observation decks and interpretive signage to make this an enjoyable and rewarding family destination.