Residential and industrial developments are the single greatest threat to the health of the Credit River and many other rivers situated near urban areas. Development is inevitable, but it does not have to destroy the river or the great fishery we enjoy.

Urbanized areas have many negative impacts on the watershed, but flooding, loss of ground water and soil erosion are by far the greatest threats. In the pictures you can see soil pilled high, all over the road and ready to erode into the river.

Flooding and loss of ground water:

Roof tops, patios, driveways and roads are all impermeable so water runs off them without filtering into the ground. Most urban areas are covered with 60% or more impermeable areas, therefore 60% of precipitation or more never enters the ground and the water table. The precipitation is rushed off the roof or the road and usually into a storm sewer where it flows in a pipe underground until it pours into the river. There are hundreds of storm sewers dumping flood waters into the Credit River at this time, with new ones added constantly. The fast runoff and the prevention of filtering into the ground causes ground water levels to fall, which causes lower summer water levels and loss of cold spring water which is necessary for trout and salmon. The storm water causes serious flooding which cause the stream banks to erode quickly and the river to become wider and shallower to accommodate the high water levels, filling in pools and destroying spawning areas.

Muddy water from a recently developed area entering Levis Creek.

Storm Sewers:

Storm sewers not only cause more severe flooding, they also dump polluted waters directly into the river following light rain. Water from storm sewers often runs black after light rain due to debris, oil and gas on roadways and usually becomes brown after heavy rain from erosion and silt that has been deposited in the sewer from development.

Black water from a storm sewer dumping into the Credit River at Creditview Road (North of Britannia).

Muddy water from a storm sewer dumping into the Credit River after rain.

Soil Erosion:

As you can see from the photos, soil erosion is obvious and severe. Acres of exposed soils dump thousands of cubic metres of silt into the river following heavy rains burying spawning areas and smothering insect life necessary for trout and salmon to feed on. Soil erosion causes the river to remain muddy for several days following heavy rain, preventing fishing and stressing the fish. Rivers in healthy ecosystems remain clear following rain, but the Credit River is under so much development pressure it turns brown following only light rain.

Destroying the River is PREVENTABLE:

In the past few years newly developed areas have been required to build storm water ponds. Unfortunately they are still to small and ineffective at preventing flooding and soil erosion, but they are a step in the right direction. Storm water ponds can be built to hold back storm water flooding and release it slowly, after the silt has settled. Storm water ponds are also able to release cold, clean water to the river using bottom draw techniques, thus eliminating flooding and silt and lowing water temperatures for improved trout and salmon survival.

Other Threats