Drainage System Maintenance
Storm Water Drainage System Maintenance
In 2002, Hartman & Associates, Inc., under contract with the City, produced a Stormwater Master Plan. It was updated in 2009 under contract with Quentin L. Hampton Associates. These two studies identified areas of the City that experienced localized flooding during heavy rain events, and grant monies were obtained to implement projects that modified the drainage system. Over the past decade, the City has made major strides toward reducing localized flooding. It began with the installation of storm sewers and Miami curbing (shallow dip concrete curbs that are more pedestrian-friendly) in the downtown Community Redevelopment District. Soon afterward there followed a vegetated swale project in Mirror Lake. Of the eight neighborhoods identified in the Stormwater Master Plan, seven have had vegetated swales constructed, most recently Palma Vista Subdivision and South Flagler Avenue between 9th and 13th Streets.
A vegetated swale is an open channel used to convey stormwater. A drain with an underground pipe is installed in the driveway to minimize the dip to the homeowner. This type of conveyance system has the following advantages over traditional concrete-lined ditches or storm sewers:
- They are less expensive to build (although they do take up more surface area);
- They are less expensive to maintain;
- They more closely preserve the natural hydrologic characteristics of the drainageway; and
- They clean the stormwater by filtering it through the vegetation.
By gradually varying the elevation of the swale, the force of gravity conveys the excess water to a stormdrain where it is piped to the Intracoastal Waterway (ICW) or to a retention pond.
These stormwater projects are built to handle the 25-year storm; they will not convey all the runoff expected to accumulate during the “100-Year Storm”. Swales would have to be much deeper and wider otherwise.
Help From Homeowners
Although the vegetated swales are in the right-of-way, the City needs help from homeowners for swale maintenance. Allow grass to grow in the swale, but keep it mowed. Do not allow leaves, lawn clippings, and other debris to accumulate in the drain or the swale, as this impedes flow. Never stack your yard waste in the swale while you are waiting for City pick-up. Do not park a vehicle in the swale, as its weight will compact the soil and impede filtration.
For more information about swales, please view our Save the Swales brochure (PDF).
If you have a blocked drain and need the City’s help to remove it, or if you are aware of a violation of the stormwater system regulations, such as illegal dumping, please call the Public Works Department at (386) 517-2000, ext 243.
When heavy rains coincide with high tides, the level of the ICW may be higher than the elevation of the stormdrain exit pipe. A valve has been installed to prevent backflow of ICW water into the drainage system, but it may result in the accumulation of rainwater in the swales longer than intended. Fortunately, this situation does not occur often, but if water accumulates for more than 72 hours – the amount of time it takes for mosquitoes to breed – contact the Public Works Department and a mosquito-killing tablet will be introduced to your area.