Written By: Karlee May, Digital Media Coordinator, with significant contributions from Katie Jane Harris, Environmental Planner, & Cory Harris, Water Resources Engineer
What is a Floodplain?
A floodplain is the flat areas on either side of a stream or a creek. Floods are a common occurrence in nature and floodplains are nature’s way of accommodating high water levels. When water levels are high after a rainfall, the water in the creek overflows into the floodplains where erosive energy is dissipated and the water disperses nutrients onto the soil and filters a portion of the water into the groundwater system. Floodplains function as nature’s plumbing system.In an urban area that is poorly designed to handle large storm events, the water is concentrated in a narrow channel that lends to deep, fast, flowing water. The area will flood regardless of urban infrastructure but we can plan ahead of time to reduce flooding in one area while directing it elsewhere.
What Does Conservation Halton Do?
Reservoirs and dams are man-made structures we use to control flooding but they are still fallible and very costly to construct and maintain. Impermeable surfaces, like roofs, driveways, and roads (which also compact the ground and limit infiltration) intensify stormwater run-off. The best option to minimize and prevent flooding is to protect wetlands and other low-lying areas and direct development outside of floodplains: it is best to leave nature to manage itself rather than to risk life and property. Reservoirs and dams cannot contain all floods but can mitigate flooding impacts, especially when used in conjunction with the existing natural systems like riparian areas, forests, and wetlands. As Cory Harris mentioned in the previous post, Conservation Halton balances the needs of Halton region residents and the natural processes of our watershed. We are responsible for the maintenance and operation of four major dams and 12.5 kilometres of flood control channels–which help to prevent regular flooding of areas of historic development such as older portions of Milton, Burlington and Oakville. We continuously monitor climate and weather conditions for future planning and flood warning advisories.
What Can We Do?
Public education is always at the forefront of Conservation Halton’s mandate: the symbiosis of the community and nature together. Homeowners can take many measures to protect the watershed and alleviate pressures on the storm water system–like disconnecting drain pipes, and installing permeable driveways. Homeowners can insist developers use eco-friendly measures to protect the watershed. Moreover, homeowners who have property near creeks and streams should refrain from mowing the edges; protect the riparian area, to prevent erosion (a key occurrence in flooding) and also protect endangered species.
In the next post in this series, we will discuss the Burlington Flood, the aftermath, and what we do in the wake of a flood.