ANR-577 MANAGEMENT OF RECREATIONAL FISH PONDS IN ALABAMA/Three
Management of Recreational Fish Ponds In Alabama
Pond Construction And Watershed Management
Poorly constructed ponds are always difficult to manage. Water levels
may fluctuate radically because of pond seepage or inadequate watershed
(area that drains rainfall into the pond), or both of these conditions.
Aquatic weeds may grow rapidly in shallow areas. Erosion and contamination
from the watershed may make good management impossible. For assistance in
pond construction or renovation, contact your local USDA Natural Resources
Conservation Service (NRCS) Office. The NRCS can provide assistance in design,
layout, and monitoring construction of ponds.
All ponds should be designed and maintained with the following guidelines:
- The dam should have a compacted clay core.
- Soil lining the pond should be a minimum of 30 percent clay.
- Pond size should be closely matched to watershed area.
- Banks should slope rapidly to a depth of at least 2.5 feet.
- Drains and overflow pipes should be built through the dam.
- An emergency spillway should be constructed for periods of heavy run-off.
- Livestock should have limited access to the pond.
Pond leaks because of poor construction are common. Pond dams must be
constructed with a compacted clay core that is trenched into impervious
soil or rock layer below the pond bottom. Trees or other woody vegetation
should never be allowed to grow on the dam, because roots will eventually
penetrate the core and cause the pond to leak. Drains allow water levels
to be regulated for better control of weeds, fish populations, and for easy
access to repair or renovate the pond.
Alabama ponds generally need 4 to 30 acres of watershed per acre-foot
of pond storage. Soil types, slope, and vegetation covering the watershed
will affect runoff. Generally, more area is needed if the watershed is wooded
than for open watersheds. If the watershed is too large, a diversion ditch
around the pond may be needed to keep the pond from flushing too rapidly.
Aquatic weed growth occurs most easily in shallow water. Pond banks should
slope rapidly (2:1 or 3:1 ratio) to a depth of 2.5 feet or more. Aquatic
plants do not easily establish themselves at this depth, especially if a
good algae bloom is maintained (see Fertilization).
 Photo at left: Cutting a trench for the clay core of the pond.
Livestock should be kept away from the pond. Livestock erode pond banks,
which creates shallow areas that can become infested with aquatic weeds.
Cattle also cause damage to dams. Livestock watering troughs should be built
below the dam and livestock should not be allowed to loaf in the watershed
near the pond.
Fields next to ponds should have a sod border. Sod or grass strips 50
to 100 feet wide between the field and the pond reduce soil erosion and
pesticide contamination that can cause fish kills.
|