Stormwater Pond Maintenance

Stormwater ponds are important for the overall management of rain runoff. They reduce the impact associated with increased paving and construction, which causes rain to become runoff rather than seeping directly into the soil.

Reduce Pollutants

Stormwater ponds are intended to reduce the pollutants that are transported in runoff, including oils and grease, heavy metals from cars and industrial processes, sediment and floating debris such as leaves and trash. Ponds are designed to meet specific standards established by the Florida Department of Environmental Protection, the St. Johns River Water Management District, and the City of Maitland. The pond storage volume and control structure characteristics are unique to each site served. Maintaining those specific characteristics is critical to comply with the permit for each facility. Proper maintenance helps ensure the pond’s continued functionality.

To maintain a pond to the specific stormwater criteria under which it is constructed, review the approved plans prepared for the construction of the facility. If you do not have plans, you may be able to obtain copies from the water management district. If plans are not available, consult with a professional engineer to establish the conditions to which the pond should be returned and maintained. For most ponds, a simple inspection can often indicate areas where basic maintenance is required.

Basic Maintenance Activities

Ponds are not dumping grounds for trash and other undesirable material. They are living treatment systems that behave much like natural land and lake ecosystems. Poorly maintained stormwater facilities can result in increased pollution loads entering surface waters in the City, causing reduced water quality. Poor maintenance can also contribute to flooding.

The following activities can be used to keep your pond in good condition and in compliance with the applicable rules and criteria:

• The pond berms should be free of erosion, stabilized with grass, and regularly mowed.
• The pond should be free of debris such as trash and leaves. Erosion of soil should not occur at the pipes entering the pond or the outfall structure.
• Prohibit excessive accumulation of petroleum hydrocarbons (evident by oily sheen on surface or gas/solvent odors). Remove and properly dispose of the material if present and investigate the site to find and eliminate the source.
• Prohibit woody vegetation (shrubs and trees) in the pond unless they were planted as part of the original landscape design. Remove the material including the stumps and roots and repair the ground surface.
• Designed littoral shelves (planted aquatic vegetation) should be maintained and free of exotic vegetation.
• Invasive plants (vegetation other than designed planted areas) should be removed to maintain open water on wet ponds and mowed grass areas in dry ponds.
• Control structures and related orifices, weirs, pipes, and grates should be free of debris and in good repair.
• Excessive build-up of sediments, sand bars, and muck deposits reduce the required treatment volume of the pond and should be cleaned to original specifications.
• Underdrains and exfiltration systems should be routinely checked to ensure they are clear of buildup and maintained.
• Offensive odors and fish kills are indications of excessive build-up of organic material and nutrients that should be removed and properly disposed of.
• It is important to maintain a pond to the specific stormwater criteria under which it was constructed by referring to the original approved plans. If you do not have plans, you may be able to obtain copies from the appropriate water management district or consult with a professional engineer to establish the conditions to restore and maintain the pond.
• For most ponds, a simple inspection can often indicate areas where basic restoration and/or maintenance are required.

Certain maintenance activities, such as removal of excess sediment or aquatic vegetation, may require best management practices be used to prevent turbidity and other pollutants from discharging off-site. For other components of pond maintenance, it is recommended that you consult with a design professional before proceeding with maintenance and to develop a routine maintenance plan.

The City of Maitland appreciates your cooperation in protecting local water resources by maintaining your stormwater pond to the standards and criteria it was designed to meet.