Understanding Urban Runoff, and How Individuals Impact Their Environment
More than ever before, people are becoming environmentally-conscious and want to understand how their efforts can improve biodiversity and the health of a range of organisms. This applies to those people living near bodies of water, such as lakes, streams and oceans. Urban runoff has a detrimental effect on aquatic animals and organisms. Many contaminants can sicken and kill off fish, coral and other aquatic animals. Other contaminants can lead to algae blooms which can also reduce the populations of necessary organisms.
This has a greater likelihood of occurring in and near cities and urban developments as many paved surfaces and buildings lead to a reduction of areas whereby rainfall may easily filter and penetrate the ground, but it can occur in even the smallest community to some degree. Necessary rainfall becomes easily polluted and in such cases can carry toxic substances and debris to waterways. Here are some ways the average household can help reduce urban runoff and make a difference in their local environment.
What Is Urban Runoff?
Urban runoff is much like stormwater runoff. With urban runoff, rainwater flows over areas that are saturated with water or impervious. Such rainwater does not immediately soak into the ground upon contact. Runoff increases in urban areas as there are less exposed areas that allow for seepage into the ground. The natural environment’s landscape is altered and rainwater has to work its way around paved roads, rooftops and hard surfaces. Those living in such areas can expect more water to flow to beaches or streams as there are fewer areas where it may seep into the ground.
Another issue with urban runoff is that it comes into contact with undesirable and potentially toxic substances. Homeowners, residents and nature lovers should be aware that pollutants such as hard metals, fertilizers, pesticides, oil and road grime are only a few of the less obvious contaminants that can be swept up in the runoff and make its way into area lakes, streams and waterways. There are manmade options that can decrease urban runoff and allow necessary filtration and penetration into the ground.
How Can Homeowners Reduce Their Impact?
Homeowners who want to decrease urban runoff in their area can take steps to include green infrastructure in the design of their property. This is a design element that incorporates natural systems and engineered systems to duplicate the systems found in nature. Much of the stormwater that reaches a property can be retained, treated and used to irrigate plants and more. Green infrastructure benefits include:
- Improved habitat for aquatic animals;
- Less pollutants flowing into waterways;
- Increased water absorption into the ground and available for underground wells;
- Storage and usage of stormwater for irrigation; and
- More retention of stormwater on the property.
Homeowners may also want to be more aware of the potential sources of pollutants in urban runoff. Stormwater runoff can easily be contaminated from illegal discharges, from pavement and vehicle wear; at building and construction sites, from detergents, sewer overflows, animal feces, weathering of buildings and organic matter decay. Suspended solids, micro-organisms, heavy metals and surfactant can come into contact with the runoff and make their way into local ecosystems.
One of the biggest concerns with stormwater is the affect it has on the salmon population. The toxins in the stormwater can actually kill the fish, but that is not the only threat they face from it. Even the salmon who survive swimming in this polluted water are in danger. There are sensors on their bodies that help them find food and locate predators, along with finding locations they need to head toward or away from. These sensors are thin and like hairs, and the stormwater runoff can damage those sensors. When salmon cannot find what they need to live, spawn, eat, and avoid danger, their chances of surviving are drastically reduced.
Fish and aquatic life can be negatively impacted by surfactants such as oils, detergents and soaps. Aquatic life can also ingest and become ill or die from litter and debris. Those who want to protect the biodiversity of local waterways can take steps to decrease the amount of urban runoff making its way off a property and provide means to allow for water filtration and ground absorption on their property.
Easy Ways to Keep Waterways Clean
Property owners can do their part to help the aquatic life and ecosystems in their area. One can look for and remove any potential trash that may be easily swept up in runoff, such as cigarette butts, soft drink cups, plastic bags and other immediately observable trash and debris. Additional ways to reduce urban runoff is to increase garden areas and redirect urban runoff to locations with low lying vegetation.
Runoff may also be collected in containers for later use. Gardening and the use of rain barrels can help property owners and residents do more with runoff and reduce the potential for it to be contaminated when running over large areas of land and a variety of materials. Urban gardening is one way that city dwellers can beautify their space while assisting in the reduction of stormwater runoff.
Those who want to take steps to add green infrastructure can start off with locating sources of potential pollutants, identifying where storm water runoff occurs, sketching the area and recognizing limitations. The addition of splash blocks at downspouts can direct runoff into storage containers or slow runoff speed. Landscaping can be used to control sediment runoff. These are a few of the many ways that individuals can reduce runoff and support the health of their local environment.
Justin Havre is a Calgary native and owner of Justin Havre & Associates.