The first step in determining a design is to consider the purposes for which the pond will be used. A pond built for drainage or watering livestock is not necessarily the best design for a fish pond. If the pond serves more than a single purpose, construction should reflect its primary purpose. Ponds used primarily for agricultural purposes such as water storage or watering animals should be designed to minimize adverse impacts that farming activities may have on water quality. Livestock access should be limited to a small area to reduce erosion and prevent high turbidity levels. Runoff from crop fields should be diverted with swales or berms to prevent excessive nutrient loading, siltation and contamination by pesticides.
Information on planning, design and construction of ponds is available from the United States Department of Agriculture. Contact your local Natural Resource Conservation Service (NRCS) agent and ask for Agriculture Handbook Number 590 titled: Ponds – Planning, Design, Construction.
Most ponds constructed in Florida consist of a hole excavated in fairly level ground and require minimal site maintenance. A second type is constructed where ground elevations vary significantly and requires an embankment to impound water. Safety concerns and maintenance requirements are described in Agriculture Handbook Number 590.
Your local NRCS agent can provide detailed pond construction information about site selection, soil permeability, whether a plastic liner is needed and locations for soil analysis. This information is essential in determining a pond’s natural fertility, pH (acidity) and ability to retain water.
If possible, design your pond to allow near complete draining. The ability to dewater allows for fish population renovation, bottom improvement and vegetation management. Dewatering is accomplished easily in embankment ponds through a standpipe/spillway system, while a water pump can be used in excavated ponds.
Ponds designed primarily for fishing should incorporate as much shoreline as possible. The amount of available shoreline can be increased by use of peninsulas and islands in construction. Such construction increases the “edge effect,” which results in concentration of sportfish, improves fishing success and provides more shoreline habitat for wildlife.
Ponds should be constructed with mostly steep slopes (20- to 30-degree grade) to a depth of 8 to 15 feet. Steep shorelines will naturally limit the growth of aquatic plants. A narrow band of vegetation benefits the pond by providing fish and wildlife habitat and preventing shoreline erosion. However, excessive plant growth can cause problems. Sodding or stabilizing the land adjacent to the pond immediately after construction also will reduce erosion. Digging ponds deeper than 15 feet does not increase fish production, and deep ponds can develop serious water quality problems if thermal stratification occurs.
Fish tend to congregate in these areas, making it easy for anglers to catch them. You can create structure during pond construction by leaving elevated outcroppings or rock piles or by installing fish attractors made of tree limbs or other man-made fish attractors sold through aquatic management supply companies.
Prior to starting construction, check with your county, Florida Department of Environmental Protection (DEP), Water Management District (WMD), and the U.S. Army Corps of Engineers (USACE) for any permit requirements.
Aquatic plants growing in and around a pond provide many benefits. They help maintain good water quality by reducing erosion and absorbing nutrients. Plants provide cover for fish and a substrate for the colonization of minute organisms used by small fishes. Wildlife will use the shoreline vegetation for concealment and as areas to search for food.
Properly designed ponds with a narrow fringe of vegetation seldom develop problems. You can maintain access sites simply by removing excess vegetation by hand. Planting desirable species will allow you to maximize the biological, aesthetic and recreational potential of the pond. A mixture of submerged (below water), emergent (stems below and leaves above water) and shoreline (entire plant out of water, but can tolerate occasional flooding) species are recommended for “aquascaping”. When established, these plants may out-compete problem species such as cattails and torpedo grass. The introduction of any exotic plant is prohibited by law. Planting around islands will provide excellent habitat for wildlife that will not interfere with bank angling. You may need to obtain a permit from the DEP prior to any plant collection or transplanting activities. Florida DEP also can provide information pertaining to private companies who specialize in aquascaping and aquatic plant control.
Excessive gradual slopes, shallow ponds and the introduction of problematic exotic plants such as hydrilla and water hyacinth can lead to overgrowth of vegetation. When plants become too abundant, recreational use is restricted and the ability of predators (bass) to feed on prey (bluegill) is reduced. Growth rates of both bass and bluegill will decrease, and fishing quality will decline. In some instances, excessive plant growth will deplete DO and may cause fish kills.
The Florida DEP, the Florida Cooperative Extension Service or any FWC regional office can assist you with aquatic plant identification and management advice.
The three methods for controlling nuisance plants are mechanical (removal by hand or machine), chemical (herbicides) and biological (triploid grass carp and hyacinth weevil).
When a biological agent can provide adequate vegetation control, it is usually recommended over the use of chemicals. Triploid grass carp can be an effective tool to control certain plant species. Since triploid grass carp are an exotic fish and importation of all such species is strictly regulated, you should refer to the FWC Web site, or contact the appropriate FWC regional office to obtain a permit application. A biologist may inspect the pond, and if appropriate, will issue a permit to allow you to purchase a specified number of triploid grass carp. You may be required to install a fish barrier to prevent the carp from escaping to another water body. Only certified triploid grass carp are allowed for use since these fish are sterile.
The least desirable method for vegetation control is herbicidal, but occasionally chemical control is less expensive or the most practical method. In extreme situations, a chemical treatment followed by the stocking of grass carp to maintain control, is a viable solution.