FLOOD01312

• County: Statewide
• Title: Multi-Objective Flood Mitigation Plan for Vermillion River Basin-South Dakota
• Date: 1/1/1994
• Prepared For: South Dakota
• Prepared By: FEMA
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

,d many additional activities are avall-
I Vermillion Lake, which receives a
IX of visitors from the SioUIX Falls met-
lrea. Basin residents go down to the
liver for boating, swimming, camp-
picnicking because recreation
and access are more readily avail-
than along the Vermillion River.

operations, and some is suffered by the small
towns that dot the farming landscape.
It is commonly believed that flooding in
the Basin is getting worse, but there is really
no way to compare present conditions to floods
that occurred 15, 50, or 200 years ago. In all
probability, some human activities have con-
tributed to the flood problem-unsuitable

lion Dam was built on the East Fork to provide
irrigation and recreation, but it has little flood
control capacity. Several smaller dams have
been built on the forks and tributaries of the
Vermillion River, mostly to impound water
rather than to control flooding. In 1983 the
U.S. Soil Conservation Service finished a plan
for improvements in the Turkey and Clay

@ITUATION

,dies of water; the Vermillion River
overflows its banks from time to
, results in acute and chronic flood-
, typical of many rural, agricultural
Dughout the country. The low topo-
lief, local land use practices; the rates
ation, evaporation, transpiration, and
eeze/thaw cycles, and groundwater
:ontribute to the intensity of floods.
waters inundate farmlands, impede
al drainage an,! community storm-
off, damage roads, and enter homes
esses. Measured in monetary terms,
he damage is done to agricultural

land use practices, people living in the river's
floodplains and low areas, and natural flood
storage areas (wetlands) that have been
drained, for example. It is also possible that a
meteorological "wet cycle" is taking place.
Probably the true "cause" is some combination
of all these things, and others.
Over the past few decades, many attempts
have been made to alleviate the flooding in the
Vermillion Basin; many other ideas have been
suggested but not adopted or carried out. The
river has been channelized from about 11 miles
below Centerville to 2 miles above Vermillion.
There are over 50 miles oflevees on both sides
of the lower Vermillion River from Vermillion
to about 2 miles above Long Creek. East Vennil-

.

Creek watersheds in the lower part of the
Basin, but it was not implemented because
there was no local sponsorship. In 1987 the
Corps of Engineers began a 5-year study of
Basin flooding, but no cost-effective solutions
that met the Corps' criteria were found.
At the same time, the residents' concern
about other water-related issues has been grow-
ing, too. The U.S. Geological Survey and the
South Dakota Geological Survey examined the
quantity and quality of groundwater in Turner
County in 1990. The Statewide Comprehensive
Outdoor Recreation Plan, completed in 1992,
outlined ways to handle growing pressure on
South Dakota's recreational resources, espe-
cially lakes, streams, and wetlands. The area is