A cost-effective way to treat excess runoff

In 2002, the state passed enabling legislation, the Rhode Island Stormwater Management and Utility Act that allows cities and towns to establish stormwater utilities.
Stormwater utilities would be similar to each municipality’s water and sewer departments and would assess fees based on the amount of stormwater runoff produced by each developed property. These fees would be used to build infrastructure to reduce the pollution problems caused by stormwater runoff.
The pollution problems in Rhode Island are caused mainly by combined sewage overflows at local sewage-treatment plants and stormwater runoff. There are ways to greatly reduce these pollution problems in a fiscally prudent manner without building very expensive new sewer systems.
The first – and most important – way to avoid huge capital expenses is to fund these new infrastructure projects on a pay-as-you-go basis. The elimination of bonding fees and interest fees would reduce the cost of each project by 50 percent. Homeowners and businesses would like this idea.
Next, Senesco Marine, a company located at Quonset Point, has the expertise to design and build large, steel, rectangular tanks to store sewage overflow and stormwater runoff until it can treated during dry weather. These tanks could be built at Quonset, floated to areas where needed and installed in below ground-level, concrete foundations. These tanks would end up 10-15 feet below ground level.
Horizontal directional drilling could then be used to drill pipe lines along the streets in Rhode Island’s bayside and riverside areas to collect the excess runoff. Because such drilling does not require the digging of trenches, construction would proceed rapidly with few traffic disruptions and minor community inconvenience.
Storm drains and catch basins would be installed along each street to channel the runoff to the new pipe lines. These new pipe lines would then be connected to the newly installed wastewater storage tanks.
Storm-drain and catch-basin systems do not have to be connected to homes and businesses. In addition, the number of storm drains and catch basins on each street would be small, as would the number of wastewater-storage tanks needed.
Building this wastewater-storage system will not be complicated and the drilling machines will do most of the work underground and out of sight. In the 1990s, horizontal directional drilling was used to drill a 30-inch diameter, 10-mile pipe line under the Providence River to bring Scituate Reservoir water to Bristol County.
Finally, Rhode Island should build a series of wastewater wetland treatment systems. Modern sewage-treatment facilities now incorporate constructed wetland systems as part of their wastewater-treatment procedures because they are relatively inexpensive to build and require very little maintenance. Plant life in these systems naturally remove pollutants from wastewater, (especially nitrogen and phosphorus), and provide homes for many animal species.
The new wastewater-storage tanks would be connected to these wetland-treatment systems. This wastewater would be channeled through the newly constructed wetlands and the pollutants would be naturally removed. Where built, these constructed wetland systems have become tourist attractions and are being used as outdoor classrooms for public school and college students. •


Kenneth Berwick is a retired school teacher in the Lincoln School system.

No posts to display