Retention Ponds: Drowning Hazards Hidden in Full View
Tuesday, December 6, 2022
The objective of this article is to call attention to a danger that often goes unrecognized, and to urge involvement by aquatics professionals to support safeguards against this hazard.
Among the types of aquatic environments, it can be argued that retention ponds are the most dangerous. Retention ponds are manmade water bodies engineered and permitted to manage storm drainage. There are two types. Dry retention ponds remain without water until a major rain event happens. Wet retention ponds are full year round, but their water level often significantly fluctuates.
Children are highly attracted to water, so without barriers and other safety measures, retention ponds pose a drowning risk. This especially holds true among children suffering from autism, many of whom have no fear of water.
They also can be particularly dangerous to teenage boys, who tend to be risk takers, according to psychologist Dr. Dianna Sullivan. Some retention ponds include fountains in the middle, which can represent a challenge to swim around for teens.
In the midwestern and northern states, the ponds become even more dangerous in winter, when they freeze and sometimes don’t have enough thickness to support a person’s weight.
It isn’t possible to determine how many people fatally drown in retention ponds, as reports often do not differentiate them. Over a seven-day period in September 2022, three children — ages, 3, 4 and 4 — drowned in these ponds in Southeast Florida. In Indiana, 25 known fatal retention-pond drownings occurred between 2007 and 2017.
In housing developments, retention ponds sometimes are represented as lakes — in some cases, as recreation lakes. When this happens, people often believe it is safe to canoe, kayak, paddle board, fish and swim in them, unaware of the hidden drowning hazards, or that they are not intended for recreational use. In many cases, retention pond water is contaminated. Toxic metals from gasoline, oil and asphalt often accumulate on the bottom, making it hazardous not only to fish and birds but also to humans.
While few codes or standards exist that apply to retention ponds, there are several best practices that should be employed to mitigate their hazards.
Currently, discussions are taking place in some counties about prohibiting the building of ponds near parks, playgrounds and school campuses. Legislative action can be a first step in reducing drownings in these settings. Aquatics professionals can help by supporting this legislation.
In housing developments, fences should be constructed to prevent access to ponds, especially by children. Until fences become mandatory, their construction should be done based on best practices. It is important to note that the “best practice” justification meets a legal standard when developing a theory of negligence in a civil case.
It is crucial that the floors of retention ponds meet slope guidelines, which call for a 4:1 gradient leading from the shoreline to the water. This means the floor can drop 1 foot over the course of 4 feet of horizontal run. This profile helps prevent individuals from accidentally slipping or falling into the pond. The slope must continue underwater. Individuals swimming in retention ponds often believe that ponds have a gradually sloping bottom leading from shallow to deeper water. However, many ponds have sudden drop-offs, causing individuals to experience a instant transition from knee- or chest-deep water to water that is overhead.
Considering the importance of the 4:1 profile, homeowners and condominium owners associations should conduct frequent risk assessments to insure the ponds remain in compliance.
Additionally, HOAs and property management companies must never refer to retention ponds as lakes. Doing so gives the public a false sense of safety. Calling a retention pond a lake and then allowing (in some cases, encouraging) recreational use represents negligence. In some cases, the water is dyed blue, making them aesthetically appealing and further encouraging ponds for recreation use. Additionally, retention ponds are sometimes stocked with fish. Fishing from shore with slope profiles that are less than 4:1 may be hazardous.
Any retention pond located in a housing development or an urban area should have strategically placed, encased lifesaving rings set around the pond, at least every 300 feet.
Additionally “No Swimming” warnings should be posted, complying with ANSI warning sign requirements pertaining to the letter’s color, shape and size.
In areas of the south, retention ponds provide habitat for alligators. Measures must be taken to remove alligators from retention ponds, especially those located in housing developments.
Usually later in the summer and as the water warms, many ponds have underwater vegetation that may entangle a bather. Vegetation should be promptly removed and/or controlled by licensed companies specializing in aquatic weed control.
Water should be periodically tested for contaminants. If the water is contaminated, signs must be posted to indicate this, and measures must be taken to solve the problem.
In summary, retention ponds often present hazardous conditions that members of the public don’t realize. They are especially hazardous to young children, as it is not realistic for parents, especially those having several children, to maintain constant visual supervision.
Therefore, it is necessary for homeowners associations and property managers to take the proactive measures recommended in this article to prevent drowning in retention ponds. Never should retention ponds be represented as lakes and never should recreation activities be allowed.