POND CONSTRUCTION AND DESIGN IN NIGERIA

Commercial Catfish Production
Pond Construction Proper design and construction of
ponds is critical to the success of a
commercial catfish operation.
Well-designed ponds, constructed
on soil with a proper clay content
and adequate water supply, have a useful life of at least 10 years. Pond Types Three types of ponds are used in
catfish farming. The first, called embankment or
levee ponds, is the most common
type of pond used in channel
catfish farming. Embankment
ponds are the preferred type for
large-scale catfish farming because they can be built in large
contiguous tracts, which aids in
pond management. Embankment
ponds are built on flat land by
removing soil from the area that
will be the pond bottom and using that soil to form levees or
embankments around the pond
perimeter. The second type, watershed
ponds, are built in hilly areas by
damming a small stream. In the
long term, the major source of
water is runoff from the drainage
basin above the dam, although a source of pumped water is
desirable to help offset
evaporation and seepage during
droughts. Watershed ponds
represent less than 10 percent of
the total pond area devoted to channel catfish farming, but are
common in some regions, such as
western Alabama. The third pond type is a hybrid
between embankment and
watershed ponds. These ponds
may have two or three sides
consisting of embankments
(actually low dams) across a relatively small drainage basin. A
significant amount of water may
be obtained from runoff, but
because the catchment area above
the pond is relatively small, a
source of pumped water also must be available. Hybrid watershed-
embankment ponds are built in
regions with gently rolling
topography, such as the Blackland
Prairie of east Mississippi. Pond Morphology The ideal size and depth of catfish
ponds has changed in recent
years. Fish farmers report that
smaller ponds (8 to 10 acres) are
easier to manage and feed than
larger ponds (18 to 25 acres). Research indicates and producers
confirm that deeper ponds (5 to 6
feet average depth) have a longer
life expectancy and allow greater
water conservation. A bottom
slope of 0.2 to 0.3 inches per 100 linear feet along the long axis is
recommended for adequate
drainage. Interior levees should have a
minimum top width of 16 feet to
allow vehicle access for
management purposes even in
wet conditions. Main access levees
should have a minimum top width of 20 feet (preferably 25 feet) to
accommodate fixed equipment
such as wells, generators, and
aerators while permitting passage
of feed delivery and hauling
trucks. These main levees should be graveled for all-weather access. Slope is expressed as the
horizontal distance (in feet) that
results in a 1-foot change in
height. For most soils, an outside
levee slope of 3:1 is
recommended. Inside slope for commercial ponds typically ranges
from 3:1 to 4:1. A single 10-inch diameter drain of
heavy gauge, coated metal or PVC
pie is adequate to maintain water
level and drain a commercial
pond. The drain should extend
into the pond and past the outside levee toe by at least 5 feet. A
perimeter drainage system should
be constructed to receive effluents
and to prevent water from
standing outside levees.

Share this: