Management of Fish Ponds in Pennsylvania
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Management of
Fish Ponds in
Pennsylvania
College of Agricultural Sciences Agricultural Research and Cooperative
Extension○
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Table of Contents About This Publication Where to Get Help with
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Pond Management
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3 About This Publication Ponds are a common feature of
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Pennsylvania’s landscape. Although they Assistance with pond management is
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3 Where to Get Help with Pond
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occur naturally in some parts of the available from a variety of sources. In
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Management
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state, thousands also have been con- addition to county Cooperative Exten-
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structed for a variety of purposes. Many sion offices, local offices of the Natural
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4 Developing Objectives for Your
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were built under the technical supervi- Resources Conservation Service
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Pond
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sion of the United States Natural (NRCS), Pennsylvania Fish and Boat
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4 Planning a New Pond Resources Conservation Service (for- Commission (PFBC), and Pennsylvania
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merly the Soil Conservation Service), Department of Environmental Protec-
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6 Design
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largely to assist farming operations. In tion (DEP) may be able to advise pond
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more recent years, the recreational uses owners. Often, consultants are hired to
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8 Construction
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of ponds have become more important implement major pond management
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10 Maintenance to pond owners. practices. The agencies listed below or
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your local Yellow Pages may be able to
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12 Water Quality
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Regardless of a pond’s intended use, its direct you to local pond
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consultants.
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12 Physical Water Quality management can be difficult and
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complex. Even with careful planning,
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14 Chemical Water Quality many ponds do not meet the objectives
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Sources of Assistance
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of their owners or serve their intended
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15 Biological Water Quality
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purposes. Fortunately, management
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PA Fish and Boat Commission
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techniques are available to help you deal
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16 Testing Your Pond Water Quality
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Phone: (717) 705-7800
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with almost any pond problem.
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Check phone book for local
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16 Pond Fisheries Management
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The purpose of this publication is to number.
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16 Warmwater Versus Coldwater provide general information about a
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http://www.state.pa.us/PA_Exec/
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Fish_Boat/
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wide variety of pond management
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17 Warmwater Pond Management
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principles applicable to Pennsylvania. It
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PA Department of Environmental
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20 Management of Trout Ponds is not intended to be a complete or
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Protection
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exhaustive guide. References are given in
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23 Sources of Fish for Stocking Ponds Phone: (717) 783-2300
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the text to more comprehensive publica-
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Check phone book for regional
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tions and Web pages where they are
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23 Regulations and Laws Affecting
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office.
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Fish Ponds available.
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http://www.dep.state.pa.us/
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24 Aquaculture Although some generalizations can be
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Natural Resources Conservation
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applied to pond management, each
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24 Aquatic Plants and Algae Service
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pond is unique and may require specific
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Phone: (717) 237-2200 (Pennsyl-
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treatment to achieve a desired result.
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25 Identification of Plants and Algae
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vania office)
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When the general recommendations of
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Check phone book for local office.
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26 Causes of Plant and Algae Growth this publication appear to be inad-
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equate, you are encouraged to seek http://www.nrcs.usda.gov/
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26 Preventing Plant and Algae Growth
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additional professional assistance.
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Penn State Cooperative Extension
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27 Control of Plant and Algae Growth
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Check phone book for county
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office.
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29 Miscellaneous Troubles and
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http://www.extension.psu.edu/
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Treatments
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3with a trout fishery as the objective.
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Developing Objectives for Recognize the limitations of the Planning a New Pond
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Your Pond
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resources available, then develop
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When deciding where to locate a new
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objectives and plans that fall within
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You may have a wide variety of reasons these limitations. This will make pond on your property, you should
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for building or owning a pond. The first consider several critical factors. These
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management of the pond easier, less
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and most important step of proper include topography, land use, soil
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costly, and more satisfying and
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pond management is choosing your rewarding. texture, and water supply. In some cases,
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these factors may limit the pond
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primary objective or use for your pond
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location to one site. Where these factors
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and understanding the limitations this Ponds are frequently used in several
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will place on other uses of the pond. For ways to satisfy more than one objective. are equally satisfactory at several
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example, small ponds today are com- For example, having water available in locations, appearance and convenience
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monly used to aesthetically enhance the the pond for fire protection usually does will play a role in site selection.
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landscape, but their relatively simple not conflict with other objectives such
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construction may not provide the best as swimming or fishing. Multiple-use For example, a pond located near a
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facilities for other activities like swim- ponds are fine as long as the uses are house, where it can be observed
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ming, boating, and fishing. The compatible. When conflicting or frequently and conveniently, is safer and
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importance of establishing objectives for incompatible uses are desired, you must more desirable for family recreation. It
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the projected uses of a given pond can be used as a source of water for fire
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assign priorities to your objectives. For
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cannot be overemphasized. Careful protection or for irrigating a small
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example, the objective of providing for
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consideration of use compatibility and swimming may conflict directly with garden. Road access to the pond is
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use priorities is essential in planning a important if it is to be used for fire
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the objective of having water available
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new pond. protection, so fire trucks can drive to
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for irrigation. Irrigation needs may
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lower the water level to a point where within 15 feet of the water.
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In dealing with an existing pond, you swimming is impossible, at a time when
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The size of the pond will be determined
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will need a slightly different approach. it is most wanted. If this occurs, you
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Make an appraisal, or have one made, must decide which objective is most by the site characteristics and money
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that describes the existing pond and its important. Sometimes planning and you want to spend on construction and
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potential for management. For example, management can eliminate or at least maintenance. Keep in mind that small
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if the water quality is unacceptable for reduce these conflicts. This is one reason ponds are not easy to manage for fish.
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trout, it would be pointless to spend a for listing and prioritizing specific Normally, ponds of less than 1/4 acre in
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great deal of time developing a plan objectives. surface area are too small for effective
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management of warmwater fish. Ponds
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as small as 1/10 acre in surface area may
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Table 1. The most common primary uses of ponds, from a survey of 557 pond be suitable for trout, however, if they
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have appropriate water quality.
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owners throughout Pennsylvania.
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Pond Use Percent of Respondents
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Aesthetic Beauty 45%
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Fishing 21
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Wildlife Habitat 11
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Swimming 7
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Animal Drinking Water 6
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Fire Protection 6
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Irrigation 1
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Other 3
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4subsurface seepage are adequate during
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even the driest years. Normally, a
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drainage area of 10 to 20 acres yields
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sufficient water for a one-acre pond in
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Pennsylvania.
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Land use around the water supply is
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critical in determining the water quality
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of the pond. All sources of water
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contributing to the pond should be free
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of sediment, pesticides, and other forms
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of pollution. It is generally a good idea
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to establish a buffer strip of vegetation
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around the pond to trap sediment and
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keep it out of the water. Ponds also
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commonly suffer from excessive
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amounts of nitrogen and other nutri-
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ents. These nutrients often originate
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from animal or human waste or
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fertilizers from nearby barnyards, crop
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fields, and septic systems. Drainage
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from these areas should be diverted
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away from the pond, since too much
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nitrogen and other nutrients will cause
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The Pond Watershed Soil texture must be considered when excessive growth of weeds and algae.
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The area of land surrounding the pond selecting the pond site. The bottom of
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the pond, the banks, and the earth fill Construction Permits
that contributes water to it is known as ○
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placed in the dam must contain enough
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the pond watershed. Understanding the
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Permits for the construction of ponds or
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pond watershed is important, because clay or silt to prevent seepage and make dams may be required, depending on
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the reservoir hold water. Normally, areas
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anything that occurs within this area the size of the drainage area, the height
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can affect the pond. Locating a pond in that include exposed bedrock or beds of
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of the dam, and the capacity of the
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an undisturbed area or minimizing sand or gravel are not satisfactory. impoundment. A permit is required for
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Anyone who is considering building a
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disturbance and land use changes within the construction of any dam that
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the pond watershed are important pond should have the soils and geologi-
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impounds the runoff from a drainage
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components of managing a pond. cal conditions in the area checked by a area that exceeds 100 acres or provides a
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professional consultant knowledgeable maximum storage capacity of 50 acre-
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and competent in making site
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The ideal topography for a pond feet of water (about 16.3 million
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watershed is a natural depression or a investigations. gallons). A permit also is required for
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broad drainage with a narrow neck at its any pond with a dam more than 15 feet
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lower end where only a short dam will Water Supply high, even if the pond’s only source of
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be needed. The most economical site is
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Springs, seeps, and small streams are water is a spring, a well, or a small
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one that will require the smallest dam pipeline from a stream. Permits are not
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typically the best sources of water for
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and the least amount of work for the required for ponds that do not exceed
ponds. They usually provide cool and
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size of the pond created. Small ponds
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relatively clean water suitable for most these specifications.
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collecting runoff from large drainage
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pond uses. If an obvious water supply is
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areas require expensive overflow and Contact your local Pennsylvania DEP
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not available, direct surface runoff from
spillway systems to handle water safely.
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the surrounding land can be the office for more information and to
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obtain the necessary permit application.
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primary source of water to maintain the
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The office telephone number and
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level of a pond. The drainage area
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should be large enough to ensure that location can be found in the state
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government pages of your local phone
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the combined surface runoff and
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book.
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5Safety and Liability Concerns Although many pond owners willingly
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allow use of their land and water areas Design
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Safety and liability are legitimate
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for varied recreational purposes, liability
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concerns of all landowners, and ponds
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for accidents is a justifiable concern. To Ponds designed and constructed
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create an additional reason for concern.
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address this issue, Pennsylvania enacted according to recommended standards
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Ponds may pose a downstream threat,
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a law that has as its purpose “encourag- are relatively safe, easy to manage, and
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and consequently the aforementioned
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ing landowners to make land and water fairly economical to build. Ponds
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permits are required to ensure proper
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areas available to the public for recre- constructed haphazardly are unsatisfac-
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construction.
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ational purposes by limiting liability in tory and difficult to maintain. It pays to
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connection therewith, and repealing obtain information and expert advice
Ponds, like any body of water, attract
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certain acts.” This law generally limits before you start construction. This
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people. When the two come together,
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landowner liability, except for “willful or section briefly discusses the basic
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accidents sometimes can occur. Con-
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malicious failure to guard or warn components of a well-designed pond.
sider safety features when planning your
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against a dangerous condition, use,
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pond. Remove trees, stumps, and brush
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structure, or activity.” Liability also is
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that may be a hazard to swimmers. Keep For More Information on Pond
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not limited when fees are assessed for
the pond and banks free of rubbish,
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recreational uses such as fishing, Design, Construction, and
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wire, cans, bottles, and other debris.
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regulated shooting, campsite rentals, Maintenance
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After the pond is built and filled with
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and other for-fee activities.
water, mark the swimming area and Look in the U.S. Government
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post safety rules for all permitted water pages of your phone book for your
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In addition to the protection offered by
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uses. Place warning signs at all known local Natural Resources Conserva-
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this law, most landowners carry compre-
danger spots. If boating and swimming
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tion Service office. Request
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hensive liability insurance on their
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are permitted, consider building a dock Agriculture Handbook Number
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property. Some pond owners also
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or pier. Place lifesaving devices such as 590, Ponds—Planning, Design,
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choose to restrict access to their pond by
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ring buoys, ropes, or long poles near
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Construction. This 85-page color
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posting signs prohibiting tresspassing.
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swimming areas. publication gives detailed informa-
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You should consult with an attorney ○
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and an insurance agent for proper legal
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construction, including detailed
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interpretation and protection for the
illustrations.
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specific circumstances involved with
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your pond.
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6Figure 1. Pond construction.
Top of
dam at
Water level Steep banks
least 6’
wide
Adequate spillway Freeboard
Dam Outlet pipe
Antiseep collar 3:1 slope
Valve or breakable plug
Drain pipe
Core fill
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Top Width and Side Slopes of Dam Emergency Spillway Freeboard
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The top width of the dam depends on An emergency spillway is necessary to The crest, or top, of all earth dams must
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the height of the structure. In most provide a safe overflow outlet for be higher than the normal water level to
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cases, the dam should be wide enough floodwater. Be sure that your pond has keep waves and high water from
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to permit limited use as a roadway for one. The spillway should be constructed breaking over the top and cutting
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vehicles. The minimum top width in the undisturbed bank at one end of channels through the structure. After
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should be 6 feet if the dam is less than the dam. It should have a flat-bottomed settling, the top of the dam for a one-
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10 feet tall. The minimum top width channel large enough to handle the acre or smaller pond should be at least
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increases to 14 feet for a dam that is overflow caused by a 10- to 50-year 1.5 feet above the high water level or
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over 25 feet tall. rainstorm, depending on the size and the elevation of water designed to flow
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watershed area. Pennsylvania DEP through the emergency spillway (see
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All earth dams should be constructed requirements must be met for dams that ○ above). The interval between the water
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with side slopes stable enough to are large enough to require a permit (see level and the top of the dam is called the
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prevent erosion and keep the earth fill permit section). freeboard. The freeboard interval is
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in place. In most instances, a slope of 3 maintained by the emergency spillway
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feet horizontal to 1 foot vertical (3:1) on The spillway, including the side slopes and the outlet pipe.
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both the upstream and downstream and channel bottom, should be planted
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faces of the dam will be satisfactory. with a mixture of grass seed that will Outlet Pipe
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Under no circumstance should either produce a thick, tough sod. Good sod A drop- or hood-inlet pipe should be
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face of the dam or any excavated slope prevents rushing floodwater from
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installed through the dam to provide an
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be steeper than 2:1. Proper slope is scouring deep ruts in the channel. The
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outlet for the normal flow of water. The
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especially important in the shallow pond should not be filled with water pipe, which governs the depth of water
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edges of the pond. Water should be at until the sod becomes well established
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in the pond, should be positioned at a
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least 3 feet deep at a point 6 feet out and the spillway is ready for use.
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level about 12 inches below the bottom
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from the shoreline to discourage growth of the emergency spillway. The pipe
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of algae and aquatic weeds. Experience
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should be large enough to drain the full
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indicates that it is best to slope the
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pond down to normal water level within
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banks properly at the time of 24 hours after the flow through the
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construction.
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emergency spillway ends. These pipe
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sizes vary with drainage area and pond
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storage characteristics and should be
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determined by an engineering
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professional.
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7
○Drain Dry Hydrants
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Construction
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A combination outlet pipe and drain- A dry hydrant is a nonpressurized, low-
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pipe is highly desirable for pond cost pipe system installed along the
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The construction site should be cleared
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management. It can be used to drain the bank of the pond at a location accessible
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of all large rocks, trees, brush, roots, and
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pond for various fish management by fire trucks to provide easy access to
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other debris. The topsoil should be
practices, pond repairs, or emergency pond water during an emergency. It is
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removed and stockpiled for later use.
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situations. constructed from 6-inch or larger PVC
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pipe that extends from at least 2 feet
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Most earth dams should have an
The drainpipe can be closed with a below the water surface through the
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antiseepage core built into the structure.
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valve or plugged with a bell-end clay tile pond embankment and above the
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(See Figure 1.) A trench for this core
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partially filled with cement. Even a glass ground next to the pond. Dry hydrants
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should be dug along the centerline of
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jug will work. The plug should be sealed usually can be installed for less than
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the dam and then refilled and packed
in the inlet end of the pipe with asphalt ○ $1,000 and often pay for themselves
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with the best fine-grain soil available.
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cement or cement mortar. If a breakable over time in insurance premium savings.
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This trench should extend the full
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plug is used, the pond can be drained
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length of the dam and be at least 3 feet
whenever it becomes necessary, but it
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deep, preferably deeper. The core is
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will be difficult to stop the flow without
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necessary to prevent seepage and to
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draining the pond completely.
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establish a good bond with the undis-
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turbed foundation.
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Antiseep collars or drainage diaphragms
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should be placed around the drainpipe
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to prevent water from seeping along the Dry hydrant
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outside of the pipe and eroding a
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channel through the dam. When steel
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pipe is used, the collars should be metal
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plates welded to the pipe. Prefabricated
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drains with antiseep collars and drain ○
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valves may be available where culverts
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and large corrugated pipes are sold. A
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drainage diaphragm consists of sand and
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gravel surrounding the downstream
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sections of the outlet pipe.
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8Pond construction
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The earth fill used in the dam should be Precautionary measures at the time of Selecting a Contractor
○
○
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○
free of boulders, stumps, roots, tree construction may avoid some man-
○
Attention to the details of construction
○
○
○
limbs, and decaying vegetation. Organic agement problems that commonly and adherence to specifications are as
○
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material buried in the dam will eventu- occur after the pond is completed.
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important as adequate investigation and
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ally decay and leave channels through Riprap should be applied to the
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design. Careless and shoddy construc-
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○
which water can seep and cause the dam upstream face of the dam to control tion can make an otherwise safe and
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to fail. Earth fill should be spread in 6- wave erosion and discourage musk-
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adequate design worthless and can cause
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to 8-inch layers and compacted with a rats. If livestock are nearby, a fence
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failure of the dam. Adherence to
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○
heavy roller. The top of the dam should should be constructed to keep them
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specifications and prescribed construc-
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be built about 10 percent higher than from tramping along the banks and
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tion methods are the responsibility of
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the designed height, to allow for polluting the water.
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the contractor, who should have a
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settling.
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reputation for high standards of
○
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workmanship. Your local NRCS office
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The emergency spillway and exposed
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may be able to provide you with a
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faces of the dam should be planted with
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partial list of local contractors experi-
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a grass mixture to make the pond enced in pond construction. Additional
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attractive and to prevent erosion. Trees
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contractors may be found in the
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should not be planted on the dam,
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telephone directory. It may prove
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○
because their root growth may cause worthwhile to go to several ponds the
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leakage from the pond.
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contractor has constructed to see if the
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work completed appears satisfactory and
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the pond owner is satisfied with the
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work.
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9The type of equipment to be used is Check for and repair any erosion in the
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○
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○
also important. With proper construc- Maintenance spillway. Inspect and repair any fences
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tion equipment, the cost can be reduced that are used to keep livestock from
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A popular misconception is that a
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and a safer dam constructed. The accessing the dam embankment.
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contractor should have a backhoe to completed pond provides immediate
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conduct soils investigations at the benefits to the owner that last forever Be sure that any roads provided for fire
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with little maintenance. Nothing could
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proposed dam site and borrow area. A trucks are maintained for the passage of
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bulldozer can be used to clear and grub be farther from the truth. A pond heavy vehicles and are plowed following
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the area. If the borrow area is immedi- certainly requires as much or more a heavy snowfall. To maximize fire
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attention than does any comparably
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ately adjacent to the dam site, a bull- protection benefits from a pond, you
○
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dozer is also satisfactory for excavating, sized piece of land. must ensure that fire trucks have access
○
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backfilling, and placing the fill. For to the pond during all seasons of the
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Many older ponds, or those that were
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dams over 20 feet high, special equip- year and that the dry hydrant is readily
○
○
ment such as a sheepsfoot roller may be not constructed properly, may have accessible.
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needed for fill compaction. As with all fallen into disrepair. They may be
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construction, the landowner should partially silted in, develop leaks, or have Muskrat Damage
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understand the type of work that is to unsafe dams with trees growing on
○
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Muskrats may damage a pond by
○
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be performed and regularly inspect the them. Repairs to ponds are possible, but
○
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building dens in the banks. They begin
○
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construction to help ensure that the you should obtain professional assis-
burrowing 6 to 18 inches below the
○
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tance. Consult your local NRCS office
○
contractor is doing a good job.
○
waterline and angle up into the bank,
○
○
or a consulting engineer for help. If
○
○
where they construct living quarters in
○
○
Construction Costs pond renovation is going to involve
dry soil above the water line.
○
○
modifying or enlarging any dam
○
○
The cost of building a pond is highly
○
○
covered under a permit issued by the
○
○
variable, depending on site conditions The best defense against muskrat
○
○
Pennsylvania DEP, a written permit is
○
and specific features of the desired damage is a properly designed pond. A
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required to make these changes.
○
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pond. Costs can range from several wide top and sufficient freeboard will
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thousand dollars per acre to over ○ make a dam relatively safe from damage.
○
Inspection
○
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$30,000 per acre for a more unique There is little danger of leaks in dams
○
○
design. Although cheaper contractors Routine inspection and frequent with adequate top widths, because
○
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may seem appealing at first, many maintenance protects a pond, keeps it muskrats usually will not burrow
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attractive, and extends its useful life.
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cheaply built ponds end up costing their completely through. If sufficient
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owners more in the long run after costly Lack of inspection and prompt repair of freeboard is provided, the den usually
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repairs are made. problems may cause more severe will have enough ground cover over it to
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damage that is either irreparable or
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prevent a cave-in.
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more expensive to fix.
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Despite construction precautions,
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The dam structure should be checked to muskrats are likely to take up house-
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ensure it has complete grass cover and keeping in even the best-designed
○
○
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○
has not eroded. Soil should be added ponds. They are especially attracted to
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and re-seeded at the first sign of erosion. areas of emergent and submergent
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Cut the grass and keep weeds, brush,
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vegetation such as cattails. Removal of
○
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○
and trees from growing on the dam. this vegetation is one way to reduce
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Trees growing away from the dam and muskrat activity in the pond.
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pond embankments are usually accept-
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able. Check for signs of minor leaks Burrowing can be stopped by riprap-
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along the dam so they can be repaired ping the shoreline with large gravel or
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before they become more serious.
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small stones. These materials should be
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placed in a layer at least 6 inches thick,
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Remove floating debris that can clog the and should extend from at least 1 foot
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overflow pipe and emergency spillway.
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above the normal water level to at least
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Also, check the overflow inlet and outlet 3 feet below it. Riprapping also protects
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to ensure that flow is unrestricted. the shore from erosion caused by waves.
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10
○Muskrats are furbearers that can be Fixing Leaks Sodium polyphosphate is the name of a
○
○
○
○
trapped legally during parts of the year. group of chemicals used to seal pond
○
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Seepage is less likely when precautions
○
leaks. The chemicals are similar to some
○
The Pennsylvania Game Law further are taken at the time of construction.
○
○
household detergents and usually are
○
provides that any person may kill or
○
If leaks develop after the pond has
○
○
capture alive, at any time, any obtained in a white, granular form.
○
○
been filled, it will be necessary to drain
○
○
furbearing animal (except beaver) in the Treated lumpy soils break down into
the pond, let the bottom dry, then
○
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fine particles that pack together and
○
act of destroying personal property.
○
apply a sealant. Leaks usually cannot be
○
○
Poisons legally may not be used in hold water better. Small channels and
○
○
fixed without draining the pond. Before
○
○
muskrat control, but various repellents voids in the untreated soil fill with these
attempting any sealing, consult a soils
○
○
dispersed particles. The result is a
○
may be used. Contact your local
○
professional to ensure that the treat-
○
○
Wildlife Conservation Officer for relatively stable, impermeable blanket
○
○
ment is suited to the pond conditions.
○
○
further details. over the treated area.
○
○
○
○ Several products are used for sealing
○
○
Ten pounds of granulated sodium
○
○
pond leaks. One is bentonite, a soft,
○
○
polyphosphate will adequately treat 200
○
porous, moisture-absorbing mineral
○
○
square feet of pond bottom. Thoroughly
○
clay that is worked into the soil. When
○
○
mix the soil to a depth of 8 inches.
○
○
bentonite gets wet, it swells to many
○
○
Apply the polyphosphate by broadcast-
○
times its original size and stops seepage
○
○
ing or drilling. Compact the treated area
○
by filling the space between the soil
○
○
with a rubber-tired roller or a steel roller
○
○
particles. For the average pond up to
○
○
before filling the pond. Do not use a
○
○
10 feet in depth, 1 pound of bentonite
○
○
sheepsfoot roller.
per square foot will greatly reduce or
○
○
○
○
stop seepage. It should be thoroughly
○
○
Sodium polyphosphate works best in a
○
○
disced into the soil to a depth of 3 to 4
○
○
limestone soil with a high silt and clay
inches. The area then should be rolled
○
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content. It does not work as well with
○
○
several times to pack the surface.
○
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coarse-textured soils. Bentonite works
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○
○
well on coarse-textured sods, but is not
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effective on highly acidic soils.
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Leaks in an established pond sometimes
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may be eliminated by applying a 6-inch
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blanket of clay to the pond bottom. If
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clay is not available at the pond site, it
○
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may be transported from a nearby area.
○
The clay should be compacted and the
○
○
water should be returned to the pond as
○
○
quickly as possible to prevent the clay
○
from cracking because of excessive
○
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drying.
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11Dredging Pond Sediment
○
○
Physical Water Quality
○
○
Water Quality
○
○
Ponds that are filled with sediment can Temperature and dissolved oxygen
○
○
be renovated, but the process is expen-
○
○
Temperature and dissolved oxygen are
Water quality is critical to the beneficial
○
○
sive. The least expensive method is to the most important physical water
○
○
use of ponds, but the parameters and
○
○
drain, pump, or siphon the water from quality concerns for pond fishes. It is
○
○
the pond and use a bulldozer to remove levels of concern will vary depending on
○
○
desirable to check these water quality
the intended use of the pond. For
○
○
the sediment. The more expensive but parameters when they are likely to be
○
○
example, water quality criteria are much
○
○
quicker method is to remove the least satisfactory (usually July through
○
○
sediment with a dragline. If the pond is different in ponds used for animal
○
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September).
○
○
small enough, a backhoe may be used. watering or human drinking water
○
○
compared to ponds used for irrigation
○
○
Trout require cool water and high levels
○
○
or fishing. Water quality also plays a
○
○
A pond with a high inflow and without of dissolved oxygen to survive. They
○
○
a drain may require a cut through the critical role in determining the types
○ grow and survive best when water
○
and number of fish species that can live
○
○
dam at a depth lower than the pond temperatures are between 55 and 60°F
○
○
in all ponds, as well as their growth and
○
○
bottom to drain the water from the and can withstand only short time
○
○
sediment. Drain the pond before survival rates.
○
○
periods when temperatures exceed 75°F.
○
○
cutting through the embankment. After Trout also require water that is high in
○
○
Water quality is complicated by the fact
○
○
removing the sediment, you may want oxygen content; 5 parts per million
○
○
to consider constructing a bottom drain that many parameters will vary season-
○
○
(equivalent to 5 milligrams per liter) is
ally and from year to year and by
○
○
through the cut and then repairing the considered the safe minimum.
○
○
differences in water quality between the
○
○
dam.
○
○
source and the pond. Changes in water
○
○
Warmwater fish, like bass and bluegill,
quality are normal and acceptable
○
○
Sediment removed from the pond, or prefer water temperatures in the 70s and
○
○
provided that drastic changes do not
○
○
“spoil,” should be spread to promote 80s. They reproduce and grow well if
○
○
drying. To prevent silt from washing occur in a very short time period,
○
○
the temperature remains in the low 70s
○
○
into the pond or stream, place the spoil changes do not exceed extreme limits,
for several weeks during early summer.
○
○
and changes are not caused by pollut-
○
away from water bodies and establish a ○ The dissolved oxygen concentrations
○
○
ants that are directly or indirectly
○
○
vegetative buffer or sediment trap should be at least 3 parts per million (3
○
○
between the spoil and the water’s edge. problematic.
milligrams per liter) for warmwater fish.
○
○
○
○
Once the spoil dries, it can be perma-
○
○
Most ponds have not been tested for
○
○
nently seeded. Temperature and dissolved oxygen
○
○
water quality, and most pond owners
○
○
measurements must be made before
are unaware of the important water
○
○
If the pond receives excessive amounts deciding which fish species will be
○
○
quality parameters for which they
○
○
of silt, implement erosion control stocked in a pond. It is difficult or
○
○
practices in the watershed. If you do not should be testing. This section discusses
○
○
impossible to change the physical
some of the most important water
○
○
own upstream land, a small settling characteristics of pond water to make it
○
○
quality parameters for typical pond uses
○
○
basin just upstream from your pond more suitable for the types of fish you
○
○
could be built to intercept silt or debris. and describes how water testing might
○
○
prefer.
be accomplished.
○
○
○
○
○
○
Fish kills from a lack of dissolved
○
○
○
○
oxygen or excessive water temperature
○
○
occur occasionally in Pennsylvania
○
○
○
○
ponds. Refer to the “Miscellaneous
○
○
○
○
Troubles and Treatments” section on
○
○
page 29 of this publication for more
○
○
○
○
details about this problem and other
○
○
○
○
causes of fish kills in your pond.
○
○
○
○
○
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○
12Muddy water Sometimes the problem of clearing Both gypsum and alum treatments will
○
○
○
○
Muddy or cloudy water is perhaps the muddy water is not easy to solve, lower the pH of water and may reduce
○
○
○
○
most common pond water quality especially when colloidal particles yields of fish.
○
○
problem. Newly constructed ponds become suspended in the water and
○
○
○
○
nearly always have muddy water until must be precipitated by chemical action. In some cases, cloudy water is actually
○
○
○
○
grass is established around the pond. In In these cases, one of the following caused by growth of microscopic
○
○
older ponds, muddy water is aestheti- chemical additions may be effective in organisms called plankton. This can be
○
○
○
○
cally undesirable, makes swimming clearing the water: (1) Broadcast 1,000 easily determined by holding a glass of
○
○
○
○
displeasing, reduces fish growth, and pounds of ground agricultural limestone pond water up to a strong light.
○
○
interferes with fish reproduction. It may (calcium carbonate) or 740 pounds of Plankton can be observed moving
○
○
○
○
be caused by erosion from a cultivated hydrated lime per surface acre of water. around the glass of water. Plankton
○
○
○
○
or unprotected watershed, by livestock This treatment should clear a pond and blooms can be reduced using chemical
○
○
wading in the pond, by wave action applications (see “Chemical Controls”
○
keep it clear for two years or more. Do
○
○
○
eroding the banks, and by the feeding not use burned lime or quicklime section), but these treatments may
○
○
○
○
action of some bottom-dwelling fish. (calcium oxide), because it may kill the reduce the overall productivity of the
○
○
○
Attempts should be made to determine pond.
○
fish. (2) Broadcast 1,000 pounds of
○
○
the cause of the muddy water before agricultural gypsum per surface acre of
○
○
○
○
resorting to treatment. water. It may be necessary to repeat this
○
○
○
○
treatment several times a year to keep
○
○
Correcting the problem may be as the pond clean. (3) Broadcast 250
○
○
○
○
simple as diverting muddy surface pounds of aluminum sulfate (commer-
○
○
○
○
runoff away from the pond. Muddy cial alum) per surface acre. Apply
○
○
water from bank erosion can be cor- treatments weekly until the water clears.
○
○
○
○
rected by adding 3 to 4 inches of stone
○
○
○
○
or gravel riprap to exposed banks. Plankton
○
○
Occasionally, muddy water will result
○
○
○
from an overabundance of bottom-
○
○
dwelling fish such as catfish. In this
○
case, take steps to reduce their popula-
○
○
tion through fishing, trapping, or
○
○
draining the pond.
○
○
○
When muddy water results from the
○
○
action of waves stirring up the bottom
○
○
sediments, the situation may be
○
corrected by spreading a layer of hay or
○
○
straw over the bottom of the pond from
○
○
the edge to a few feet from shore. This
○
measure will have the greatest beneficial
○
○
effect in shallow areas or where wave
○
○
action is especially heavy. The mat
○
prevents the waves from picking up fine
○
○
sediments and provides food and cover
○
○
for aquatic organisms. Introducing too
○
much hay or straw, however, could
○
○
cause oxygen depletion that could result
○
○
in a fish kill.
○
○
○
○
○
○
○
○
○
○
○
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○
○
○
○
○
13Nutrient runoff Hardness
○
○
○
Hardness is a measure of the mineral
○
content of water, especially calcium and
○
○
magnesium. Ponds with hard water have
○
○
a high mineral content and are usually
○
more fertile. These ponds are more
○
○
likely to support a dense growth of
○
○
aquatic plants and algae. Soft water has
○
○
a low mineral content, which results in
○
low fertility. Ponds or lakes containing
○
○
soft water often have sparse vegetation
○
○
and clearer water.
○
○
○
○
Hardness measures are especially
○
important for the use of some aquatic
○
○
herbicides, especially the copper
○
○
○
compounds used for algae control.
○
○
Hardness concentrations above 50 mg/L
○
○
○
Chemical Water Quality Nutrients
○
as CaCO3 can interfere with the
○
○
○
effectiveness of some of these chemicals,
○
Chemical water quality in ponds is Excessive nutrients such as nitrogen and
○
○
○
important not only for fish but also for phosphorous are a common problem in requiring increased dosage.
○
○
○
other pond uses like animal watering Pennsylvania ponds. These nutrients
○
○
○
and swimming. Changes in chemical usually originate from fertilizers or Hardness also may cause a buildup of a
○
○
○
○
water quality also are usually responsible animal wastes applied within the pond whitish solid known as scale in pipes,
○
○
watering troughs, and plumbing that
○
○
for excessive growth of aquatic plants watershed. They cause excessive growth
○
○
and algae. Brief descriptions of some of of aquatic plants and algae that plague use pond water. This is an aesthetic
○
○
○
○
the most important parameters are many ponds during summer months. problem that will not harm animals
○
○
drinking the water.
○
○
given below. Nutrient levels in pond water can be
○
○
measured by testing for ammonia,
○
○
○
○
pH nitrate, and phosphate. Measurable Pesticides
○
○
○
○
The pH of a pond is a measure of the amounts of ammonia or phosphate may Ponds that are located near farm fields,
○
○
be problematic. Nitrate levels in excess
○
○
water acidity. The pH scale runs from 0 golf courses, or yards may be susceptible
○
○
of 100 mg/L may be dangerous for to pesticide pollution from surface
○
○
to 14, with values less than 7 indicating
○
○
acidic water and values greater than 7 animal watering. runoff or drift during application. Many
○
○
○
○
indicating alkaline water. Most fish pesticides, especially insecticides, are
○
○
Nutrient management techniques and highly toxic to all forms of aquatic life
○
○
species prefer a pH in the range of 6 to
○
○
9, although values as low as 5 may be best management practices such as and could also be dangerous for ponds
○
○
vegetated buffer strips and limited use
○
○
suitable for brook trout. Ponds with a used for animal watering. Pond owners
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of fertilizers and manures near ponds should be especially cautious about
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pH less than 6 are common in northern
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Pennsylvania and may result in stunted are necessary to reduce nutrient levels using pesticides near ponds or streams.
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or reduced fish populations. Ponds used and restore the pond ecosystem. A fish kill from pesticides may be
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for animal watering also should have a difficult to detect, and minute amounts
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pH between 6 and 9. of a pesticide can cause losses over a
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long period. Read and follow pesticide
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labels carefully and apply them as far
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away from ponds as possible. Since fish
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are generally much more susceptible to
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pesticides than livestock are, fish kills
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are often apparent before problems
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occur with animals.
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14Aquatic herbicides Biological Water Quality Toxic algae
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A variety of herbicides are registered for Coliform bacteria Algae growth is common in many
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use in Pennsylvania ponds to reduce or ponds when nutrient and temperature
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Coliform bacteria are a large group of
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eliminate aquatic plants and algae. The conditions are favorable. Algae growth
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many species of bacteria that can
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use of aquatic herbicides is generally normally occurs between May and
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originate from animals, plants, and soil.
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compatible with other uses of the pond, October, with a peak in late summer. At
A subgroup, fecal coliform bacteria,
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but limiting certain uses for specific least six species of blue-green algae that
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represent species that originate from
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time periods may be recommended. occur in Pennsylvania may produce
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animals, including humans. Many of
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Always read and carefully follow product toxins that are harmful to animals.
the bacteria in this group are harmless,
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labels. Warnings regarding other uses of
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but their presence indicates the poten-
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the water should be taken seriously. Toxic algae poisoning of livestock and
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tial for disease-causing bacteria also to
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Some herbicides, especially the copper- pets is rare in Pennsylvania. Symptoms
be present.
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based algaecides, are highly toxic to fish ○ include muscle tremors, diarrhea, lack
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and other aquatic life if applied in doses of coordination, collapse, labored
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Some coliform bacteria are present in all
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higher than those indicated. Others may breathing, and death. If these symptoms
ponds, but bacteria levels are highest in
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require that swimmers or animals be appear, animals should be denied access
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ponds that receive runoff containing
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denied access to the water for some to algae-contaminated water.
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animal or human waste. Ponds located
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period of time to allow the herbicide to
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near barnyards or septic systems are
break down naturally. The repeated use Toxic algae blooms can be treated using
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most vulnerable. High densities of
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of copper-based algaecides also may lead applications of copper sulfate as
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waterfowl also can contribute to
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to excessive concentrations of copper in described later in this publication.
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excessive bacteria levels. Pond water
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pond sediments. Again, this is a rare problem in Pennsyl-
cannot be treated efficiently to reduce
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vania, but it should not be overlooked if
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excessive bacteria numbers. Rather,
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Acid mine drainage symptoms appear in animals with access
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reduction must be accomplished by
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to a pond with algae.
Ponds in western Pennsylvania also are removing the source of the bacteria,
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susceptible to pollution from acid mine whether by diversion of polluted runoff
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○ Parasites
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drainage. Runoff from mined areas can or reducing direct access by animals and
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carry high concentrations of iron, waterfowl. The most common parasite problem in
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manganese, aluminum, and sulfate. ponds is swimmer’s itch. It is caused by
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Metals like iron and manganese impart The acceptable levels of bacteria will a small, free-swimming parasite that
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an objectionable taste to water that may depend on the intended use of the burrows under skin, where it dies. This
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cause intake problems for livestock. Iron pond. Ponds used for swimming should causes an itching that lasts for about a
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concentrations above 0.3 milligrams per contain fewer than 2,000 total coliform week. A brisk rubdown with a towel
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liter and manganese levels above 0.05 bacteria and 200 fecal coliform bacteria immediately after the swimmer emerges
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milligrams per liter may be sufficient to per 100 milliliters of water. Adult from the water will minimize the
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reduce water palatability to livestock. livestock should not drink pond water irritation caused by this parasite. The
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Iron is also toxic to fish at low concen- with fecal coliform bacteria above 10 most practical way to control these
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trations. Aluminum is toxic to fish per 100 milliliters, and calves should parasites is to control the snails that
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species, especially trout, when the have water free of fecal coliform serve as their intermediate hosts, by
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concentration exceeds about 0.2 bacteria. draining the pond and letting it dry for
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milligrams per liter. several months. Stocking of redear
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sunfish also may be effective, since they
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are a natural predator of snails. No
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chemicals are registered for controlling
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snails.
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15Water testing
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Pond Fisheries
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Management
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Whether for fishing or for aesthetic
○
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enjoyment, most pond owners are
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interested in developing and managing a
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pond fishery. The success of fish in a
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pond depends on the water quality, the
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pond’s construction, and the manage-
○
ment of the fish populations. The
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○
following sections give some guidelines
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for the stocking and management of
○
some common fish species in Pennsylva-
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nia ponds.
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Warmwater Versus Coldwater
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Ponds may be stocked with warmwater
○
fish such as largemouth bass and
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bluegills, or with coldwater fish such as
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trout. The decision of which type of fish
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○
to stock is determined primarily by the
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Testing Your Pond Water Quality testing, pond owners should evaluate
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temperature regime of the pond and the
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the symptoms of their pond, keeping in
○
desire of the pond owner. Other water
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Your pond water can be tested easily
○
○
mind the other special water quality quality factors such as pH may be
○
and inexpensively for many of the
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○
problems described above.
○
parameters listed above. Temperature, important to fish survival and reproduc-
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○
○ tion. Consult the water quality section
○
dissolved oxygen, pH, ammonia, ○
○
Fishing—test the water frequently, of this publication for more information
○
hardness, and various other water
○
○
especially during the summer, for
○
quality parameters can be tested using about other water quality concerns for
○
○
○
temperature, dissolved oxygen, and pH. fish.
○
kits available at most local pet stores for
○
○
Test kits from a local pet store are
○
less than $10 each.
○
○
adequate.
○
Coldwater fish like trout grow and
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survive best when water temperatures
○
Measurement of total coliform bacteria,
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Animal Drinking—test the water
○
fecal coliform bacteria, pesticides and are 55 to 60°F. Trout may be able to
○
○
○
annually for pH, nitrate, and fecal withstand temperatures of 80°F for a
○
metals, and identification of toxic algae
○
○
coliform bacteria at a certified water-
○
would require more sophisticated few hours, but long periods with
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testing laboratory.
○
testing by certified laboratories. Tests for temperatures exceeding 75°F will cause
○
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death. Many ponds get too warm
○
total and fecal coliform bacteria
○
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Swimming—test the water annually for
○
normally cost $10 to $30 each at a during the summer months to support
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total and fecal coliform bacteria at a
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trout, but they may still support a put-
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certified lab. A list of certified labs by
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certified water-testing laboratory. and-take trout fishery during cooler
○
county is available from your local Penn
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State Cooperative Extension office. months. Most ponds in Pennsylvania
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are better suited to the temperature
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requirements of warmwater species like
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Routine water testing for pollutants that
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are important for your pond will help bass and bluegill. These species will
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grow well when water temperatures
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identify problems before they become
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too serious. The following guidelines remain above 80°F for several weeks in
○
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provide some testing recommendations the summer.
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for the most common pond uses in
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Pennsylvania. They indicate only the
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most common pollutants that should be
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tested for. When doing additional
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16Warmwater Pond Management Basic ecology Population structures
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Many fish species combinations have Largemouth bass spawn the first spring Bass are often stocked alone in farm
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been tried in small artificial ponds, but that they reach 9–10 inches in length ponds in Pennsylvania. The result is a
○
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largemouth bass and bluegills have been and the water temperature reaches 60°F. self-sustaining population of small bass.
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the most successful in all parts of the Bluegills spawn at a younger age than
○
In bass-only ponds, the fish stop
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country. Pennsylvania experiences with bass, but not until later in the summer growing, regardless of age, at lengths
○
○
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largemouth bass and bluegill sunfish when the water temperature reaches 67 from 9 to 12 inches, depending on the
○
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○
range from outstanding successes to to 80°F. Unlike bass, bluegills may fertility of the pond. Very few small bass
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○
complete failures. The difference is in spawn several times during the summer
○
and no large bass are present in bass-
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the management. Recent investigations in fertile ponds if they are not too only ponds.
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at Mansfield University of Pennsylvania crowded.
○
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○
have confirmed that this species A population that contains about 3
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○
combination is capable of providing ○ Bass feed effectively on bluegills as large pounds of bluegills for every pound of
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excellent sportfishing in Pennsylvania. as one-third their own body length. bass is bass-crowded and results in
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Although bass guard their eggs and fry, relatively slow-growing bass but very
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bluegills prey upon them in a density- large bluegills. The adult bass in this
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Bass and bluegill
○
○
dependent manner; that is, the situation will be larger than in the bass-
○
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number of young bass recruited only pond because of the forage
○
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○
into the population is provided by the bluegills when they
○
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○
inversely proportional to spawn, but still rather small because
○
○
the number of nearly all the young bluegills produced
○
bluegills present. will be eaten soon after they hatch. The
○
○
Thus, bass and few bluegills that survive predation will
○
○
bluegills control grow very rapidly because the inverte-
○
each other by their
○
brate food supply will be divided among
○
predatory habits. relatively few individuals. The bass-
If bluegills are too ○
○ crowded condition provides excellent
○
○
○
○
numerous, they bluegill fishing. Many bass will be
○
○
can totally caught, but few will be larger than 2
○
○
○
○
eliminate bass pounds.
○
○
○
reproduction,
○
○
○
resulting in A community containing about 8
○
○
○
○
elimination of pounds of bluegills per pound of bass
○
○
○
bass from the has relatively few large bass present, but
○
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pond. In the a more equal representation of different
○
○
○
○
absence of bass predation, size classes than in the bass-crowded
○
○
○
bluegills become overcrowded and situation. The bluegills are crowded,
○
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○
stunted. When bass are able to spawn and few will exceed 6 inches in length.
○
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○
○
successfully, bluegills will be adequately This condition provides a great deal of
○
○
○
controlled. When bass become too
○
bass forage and allows them to achieve
○
○
dominant, very few bluegills survive
○
their maximum growth potential. Bass
○
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○
their predation and the bass become in Pennsylvania ponds like this often
○
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○
crowded and stunted. grow a pound per year, resulting in real
○
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trophy fishing.
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