Written by Gavin Ferris, Ecologist
AS SEEN IN National Community Association Institute's (CAI) publication, Common Ground
The very first fish I remember catching was a bullhead catfish. It was in a small pond in my grandparents’ HOA community that is still there today. Well, sort of. Though the pond had once been deep enough for fishing and stormwater collection, its depth is now best measured in inches rather than feet. The cattails that were once clustered near the outflow are now abundant throughout the pond. Today, the waterbody resembles the nearby wetland more than it does a pond. In the 55 years of its existence, no measures have ever been taken to mitigate against the natural process of succession.
Lake and pond succession is the natural lifecycle of any waterbody. The very tributaries that supply a waterbody with its water also carry sediment, which over time accumulates and decreases the water depth. Aquatic weeds and nuisance vegetation decompose and create additional organic sediment. And the shallower the pond becomes, the more vegetation it produces—accelerating the aging process.
The speed at which a lake or pond becomes a marsh depends upon several different factors. Some of these factors can be controlled; others can be mitigated. But it is a future that all waterbodies will face at some point in their lifespan. This is why proactive management is not only beneficial, it’s key to preserving the health, function and beauty of our freshwater resources.
A common tool recommended to HOA communities is a beneficial vegetative buffer comprised of native flowering plants and grasses. A vegetative buffer that is allowed to grow 3-5 ft out from the shoreline can help significantly reduce the amount of surface runoff, sediment and pollution entering a lake or pond during rainstorms. Establishing similar erosion controls around streams and tributaries is also a wise precaution against transported sediment. Organic matter accumulation can be further prevented in the waterbody by applying nutrient remediation products, which process excess nutrients before they can be used to fuel algae and aquatic weeds, and introducing supplemental bacteria and enzymes, which aid in the decomposition of vegetation and bottom muck.
Another consideration relating to decreased water depth is the increase in temperatures. Shallower water warms faster, leaving it prone to excess algae growth, increased submersed and emergent vegetation growth, and oxygen depletion. Lake and pond aeration can help mitigate these issues and help slow the accumulation of organic matter. Beneficial dissolved oxygen can be produced by several types of pond aeration systems, which your aquatic management professional may recommend depending on your goals and the characteristics of your waterbody. Floating fountains provide effective circulation in shallow ponds, while submersed aeration systems oxygenate deeper waterbodies from bottom to top. And new aeration alternatives like nanobubble technology can be used supplementally alongside these systems to provide additional natural benefits, including toxic cyanobacteria control and the elimination of pollutants while encouraging the growth of native wildlife and vegetation.
Eventually, the line between a pond and a wetland becomes a little blurry; after all, a wetland without vegetation is, well, just mud. Some forms of vegetation, like cattails and Phragmites, not only thrive in late-successional ponds, but actually speed the rate at which succession occurs, so removing these nuisance plants is especially important. At the same time, it is just as important to establish and promote healthy native wetland plants in order for any form of an aquatic ecosystem to persist. The species best suited for your situation will depend on your location and your ultimate aesthetic and functional goals.
One concern I often hear from community managers, especially those with aging ponds and shallow stormwater retention areas, is the production of mosquitoes. Certainly, shallow productive habitats are more conducive to mosquito breeding than open water ponds. As long as sufficient water remains to sustain them, a population of fish will prevent mosquitoes from proliferating. Amphibian and insect predators like salamanders and dragonflies are also adept at controlling mosquitoes and can be promoted with appropriate native vegetation.
Proactive management strategies can be incredibly impactful in community waterbodies, especially when introduced early on in the lake or pond’s lifespan. Eventually, though, decisions must be made about the future of a waterbody. For stormwater basins and other ponds that must meet design specifications in order to fulfill their intended function, sediment removal or dredging may eventually become a requirement. While dredging can be a tremendously expensive endeavor, a well-designed custom management plan that includes strategic hydro-raking can help prolong the need to dredge by 10 years or more and will allow your community to plan for the expense gracefully.
Aging is inevitable, even for your waterbody. It is up to us to decide if and how to intervene in that process.
Contact the experts at 888-480-LAKE (5253) for all of your lake, pond, wetland and fisheries management needs.SOLitude Lake Management is a nationwide environmental firm committed to providing sustainable solutions that improve water quality, enhance beauty, preserve natural resources and reduce our environmental footprint. SOLitude’s team of aquatic resource management professionals specializes in the development and execution of customized lake, pond, wetland and fisheries management programs that include water quality testing and restoration, nutrient remediation, algae and aquatic weed control, installation and maintenance of fountains and aeration systems, bathymetry, shoreline erosion restoration, mechanical harvesting and hydro-raking, lake vegetation studies, biological assessments, habitat evaluations, and invasive species management. Services and educational resources are available to clients nationwide, including homeowners associations, multi-family and apartment communities, golf courses, commercial developments, ranches, private landowners, reservoirs, recreational and public lakes, municipalities, drinking water authorities, parks, and state and federal agencies. SOLitude Lake Management is a proud member of the Rentokil Steritech family of companies in North America.