Page 265 - Moving the Earth_ The Workbook of Excavation

Source: MOVING THE EARTH

CHAPTER 6

PONDS AND EARTH DAMS

The discussion in this chapter will be limited to ponds varying from a hundred square yards to a
few hundred acres in area, which may be built according to the judgment of the landowner or the
contractor, rather than according to detailed specifications.
Such ponds may serve as small reservoirs for domestic and industrial use, or to provide water
for fire fighting, for animals, and for fishing and other recreation. They may also be useful in
swamp reclamation, groundwater replenishment, and flood control.
They may be made by damming streams, digging holes for streams to fill, digging below the
water table, or combinations of these techniques. Dry hollows may sometimes be converted into
ponds by diverting streams, tapping springs, or lifting underground water by means of windmills
or other pumps.

WETLANDS

During these modern times in the United States, before one can think of reforming the earth to
build a pond and, perhaps, doing away with a naturally wet area, it is necessary to consider the
subject of wetlands. Wetlands are those areas that are inundated or saturated by surface water or
groundwater at a frequency and duration sufficient to support a growth of vegetation typically
adapted for life in saturated soil conditions. Wetlands are valuable natural resources that provide
important benefits to people and the environment. They help improve water quality, reduce flood
and storm damages, provide important fish and wildlife habitat, and support hunting and fishing
activities.

Clean Water Act. In 1986 the Congress of the United States included in the Clean Water Act
provisions for the protection of wetlands. It laid on the Environmental Protection Agency (EPA),
in partnership with state and local governments, the responsibility for restoring and maintaining
the chemical, physical, and biological integrity of the nation’s waters. Consequently, the EPA is
also charged with protecting wetland resources. The major federal regulatory tool for this is
Section 404 of the Clean Water Act, which is jointly administered by the U.S. Army Corps of
Engineers and EPA.

Types of Wetlands. There are two types of wetlands, coastal and inland wetlands. The coastal
wetlands are linked to estuaries, where seawater mixes with fresh water to make a variety of salinities.
The inland wetlands have fresh water commonly in flood plains along rivers and streams, in iso-
lated depressions surrounded by dry land, and along the margins of lakes and ponds. In moving
the earth, the wetlands of concern are the inland variety, except where dredging along the coast
may have to be done.

Altering Wetlands. Physically wetlands might be altered by filling, draining, excavating, clear-
ing, flooding, diverting water away, etc. They might be altered chemically by changing nutrient
levels or introducing toxics and biologically by grazing or disrupting the natural population. Any

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