Traditional buildings capture rain from the roof and direct it immediately into the storm drain system and eventually local streams. As development becomes more and more dense, our streams have been seriously impacted by this increased flow, as well as adding minerals and other pollutants. This has had a detrimental effect on the environment and wildlife.
Bioswales have been required for many developments over the past decade but many have failed or are unattractive due to their design. The combination of parking lot and roof runoffs also complicate their effectiveness. To mitigate this problem, a new concept that is being incorporated into development is the use of rain gardens.
A rain garden is normally created by disconnecting a building's downspouts from the storm rain and directing the rainwater into a vegetative swale. The swale is designed to accommodate water from a typical rain event and allow it to infiltrate back into the soil, keeping it out of the storm water system. An overflow is installed to capture excessive rain and keep the swale from overflowing.
For nearly 2 decades, all commercial properties developed in the northwest have required water quantity and quality "bioswales" to be built and maintained within developments. Unfortunately, many have gone virtually unmaintained for years and have become overtaken by undesirable and often times noxious weeds. Part of this is due to the oversimplified belief process that when planted with native plant material, they will require no maintenance. Although in nature the same plants thrive and survive, the equilibrium required to do so has taken thousands of years. When native plants are used in a non-native environment, in poor soil, and surrounded by non-native, noxious weeds and their seeds, the native plants can often be completely choked out by the undesired vegetation.
Due to the reality that many water quantity and quality facilities become overtaken with undesirable vegetation, many municipalities in the northwest are beginning to require property owners to restore these facilities to their original design. We have worked with many municipalities to understand the varying regulations and thus have educated and certified most of our production management team to be able to maintain and renovate these facilities successfully. The Clean Water Service of Washington County, Oregon has developed a standard and training program that our production managers of all been through and become certified with. The city of Vancouver has a training and certification system in which those of our team that manage those areas have become certified in as well.