James B. Rasmus, P.E., DEE
While growing up in Southern California, beach postings and closures were not typically headline news. Today, postings and closures are commonly seen in daily newspapers. General warnings about water quality are now key features on the nightly news. Watchdog groups have entire websites dedicated to exposing water quality problems at popular locations.
Public works managers and those in the stormwater industry throughout the nation have long been aware of the looming deadlines for NPDES compliance and the penalties associated with non-compliance. This has led to a new level of importance being placed on source controls and Best Management Practices (BMPs). This is a good thing; however, the level of treatment for bodies of water where there is a high degree of public contact may require even higher levels of treatment. Of course, public education, source controls and watershed planning are the long-term answers to a healthy watershed, but these measures take time (often generations) to take effect. The public works world needs to stand back and consider the economics of more advanced levels of treatment now in locations where the long-term solution is not pragmatic.
Things to consider
Recent changes in monitoring, reporting, postings, and closures of beaches and other water bodies have resulted in a new level of public awareness and scrutiny. Since 1999, in California, Assembly Bill 411 has required increased bacteriological testing and monitoring of water bodies that have a high degree of public contact. Other states have similar requirements for recreational waters. Several agencies such as the Cityies of Santa Monica, Malibu, Dana Point, Encinitas and others are already implementing advanced levels of treatment at "end of the pipe" locations where public contact is high and tourism dollars are at stake. Typically, these agencies already have successful source control programs in place and they have supplemented these measures with advanced treatment in areas that have high recreational use.
In addition to direct contact applications there are plenty of applications such as fishery enhancement, eco-tourism, wetlands, agriculture, and other sectors that can immediately benefit from more advanced forms of runoff treatment.
The burgeoning BMP marketplace has resulted in recent advances in the removal of coarse debris, oils and grease, suspended solids removal, and sediment from runoff. When these processes are combined with commercially available filtration, ultraviolet light, and ozonation systems, the result can be a cost-effective application for advanced treatment of urban runoff.
How should APWA proceed?
There is no single best response on where to implement advanced forms of treatment of urban runoff. Initial candidates for advanced treatment of urban runoff can be determined from a review of posted locations or areas with a history of urban water quality issues. From this list of candidates, one needs to focus on those locations where there would be significant public (and thereby economic) benefits.
When a suitable project is selected for implementing more advanced forms of treatment for urban runoff, the following ideas may offer some guidance and assistance for implementing these types of systems:
James B. Rasmus can be reached at (760) 753-1120 or at email@example.com.