Excess runoff is collected in the 1,700-acre (6.9 km2) Guelph Lake Reservoir which is drained in the previous autumn, and in summer the water is released slowly to regulate the flow of the river.

[citation needed] It forms part of an attempted natural buffer along the Speed: "OPIRG-Guelph and other community groups have worked, in partnership with the City to rehabilitate the local river environment.

"The buffer provides food, habitat, and a corridor for wildlife, as well as improving water quality by minimizing erosion, acting as a filter and providing shade, to lower water temperature", increasing oxygen, thus decreasing algae and bacterial contents.

As of January 2011, efforts are being made to restore the extirpated populations of all trout species to the Speed River in Guelph.

Fish impediments, such as dams, have contributed to increasing water temperature and the prevention of migration during spawning, both of which are and continue to be a reason why no trout have been caught in Guelph in decades.