POARCH TRIBE
Constructed Wetlands Reduce NPS Pollution
Sediment bars building up from upstream croplands on a tributary in
southern Alabama prompted the Poarch Band of Creek Indians to use section 319
funds to reduce this nonpoint source pollution. These monies have enabled the
tribe to construct a wetland treatment system to reduce - pollution from
agricultural runoff on tribal lands. On the Perdido Creek tributary, sediment
and nutrients from upstream croplands--primarily vegetable gardens and
cotton--have created excessive sediment bars. The selected demonstration area
is a 3-acre site within a drainage way that had previously been channelized and
cleared of riparian vegetation. The channel is dry except when rainfall is
high.
Using section 319 funds, the tribe constructed a wetland system with
multiple compartments or cells. The initial cell will remove sediments from the
first flush--the portion of runoff immediately after a rainfall that contains
large amounts of pollutants--before it enters the constructed wetland cells.
The following cells will detain the first flush for biological treatment.
To increase its participation and knowledge of nonpoint source pollution,
the tribe constructed the system, using its own labor and equipment.
Revegetation is by natural introduction and propagation. Upstream and
downstream monitoring will evaluate vegetation before the next planting season
to determine if replanting with cattails is necessary.
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