Water quality data is still limited for both the Choctawhatchee and Pea in Alabama, with less data available for the Pea River.
Three natural factors in the watershed combine to produce the most significant water quality stressors: highly erodible soils, very intense rainfall events and a tendency for frequent and sometimes intense drought.
Erosion also contributes to increased nutrient levels in streams due to the attachment of nutrients (particularly phosphorous) to soil particles that are transported into waterways.
Drought conditions contribute to low flows that can cause low dissolved oxygen levels that stress aquatic organisms.
Water quality data between ’93 and ’97 demonstrate some D.O. levels below the fish and wildlife standard of 5.0 mg/l in headwater streams, as well as turbidity approaching levels damaging to aquatic organisms in the lower portion of the watershed. All waters within the watershed are classified as Fish and Wildlife streams. (Troy)
Double Bridges Creek demonstrates some high nutrient levels not related to wastewater treatment plant discharge. This combined with higher suspended solids and turbidity is primarily attributable to land use patterns and an abundance of unpaved roads. A poultry plant discharges to this stream. Nutrient levels in this subwatershed are two to three times higher than other parts of the watershed. Coliform bacteria was higher as well but not of great concern at this time. “There are probably more water quality concerns in the Double Bridges Creek Watershed than in any other location within the watershed.” (Troy)
Coliform bacteria risks were minimal across the watershed. In all but two cases of high bacteria levels, the source of contamination was traced to livestock access or dead livestock in streams.
Well contamination of nitrates and fecal coliform can be a problem within the watershed due to failing septic systems. Currently there is little data on this issue.
Illegal dumping of household garbage, construction debris and animal carcasses is a common problem throughout the watershed. (Troy)
Water quality in the Choctawhatchee-Pea Rivers watershed is generally good to very good. The Pea River Watershed has few water quality concerns aside from some low DO values on small streams and some sites with bacteria levels approaching the limit for full body contact. Both the Choctawhatchee mainstem and the Pea River show better water quality values in the upper basin due to a more forested land cover. The Pea river shows slightly better water quality values than the Choctawhatchee due to differences in land use patterns (90% forested vs. 70% forested)
(^ Troy Center for Environmental Research)
There has been evidence of increased agricultural activities such as chicken and hog farming, cultivation of sloping areas, and clear cutting of timber to the edge of streams.
The Pea River has four wastewater treatment plant discharges, and there are five others into the Choctawhatchee River and its tributaries.(Corps 92)
Occasional high sediment load is the primary concern on the Choctawhatchee mainstem. According to the Basins 1993 Cooperative Study 5.5 million tons of sediment enter the systems streams and reservoirs each year. Over 70% originates from gullies and unimproved roads. An additional 22 percent is from cropland. The remainder is from logging and other eroding areas. 5% of the total sediment load (about 600,000 tons) reaches Choctawhatchee Bay.
A study in 83 concluded that the majority of the sediment loads to the river were coming from the upper Choctawhatchee and Pea Rivers. Though some erosion occurs naturally an increase in mechanized farming and other activities have increased normal sediment loads. As much as 323,790 tons of sediment was discharged to Choctawhatchee Bay according to the report.
Land use patterns and their rate of erosion are as follows: cropland 8.3 tons/ac./yr., pasture/hayland 0.5, Forest Land 0.8, Other 2.3. However sources of erosion are highest from gullies, then cropland, then dirt roads, forest land, other uses, pasture, and streambanks. (NRCS)
In Florida poor water quality is attributed to waste water treatment plants, animal wastes sites and dirt road and cropland gully erosion. Three tributaries, Holmes Creek, Wrights/Tenmile Creek, and Alligator Creek are reported polluted and all receive waste water effluent. (NRCS) For more information about WQ conditions on the FL portion of the Choctawhatchee see Corps report of ’92, NRCS report of ’90 or contact Choctawhatchee Basin Alliance.
Harrand Creek just East of Enterprise is impaired due to nutirents, organic enrichment and low dissolved oxygen. The Pea currently has no sections listed for impairment
Much of the Lower Choctawhatchee and its tributaries in Florida are impaired for turbidity, nutrients, coliform and mercury.
There is less water quality data available for the upper reaches of the system to assess impairment. For additional WQ data see Troy State ’97 report.
The hydrologic system of the Choctawhatchee, consisting of surface water and groundwater has been carefully evaluated in the last decade. Surface flow is most heavily influenced by climatic conditions (primarily rainfall) and is cyclic, allowing for periods of extremely low flow as well as periods of exceptional flow and floods. Groundwater provides virtually all of the drinking water for the area, for the reason that, historically groundwater has been more reliable and less variable than surface water.
Due to localized demand and dwindling aquifer reserves (primarily centered around the more urbanized areas such as Dothan), water development alternatives are being evaluated within the basin to meet future demands for water.
“The water needs of the watershed can not fully be met by ground water without pumping the major aquifers faster than they are naturally recharged. This will inevitably result in progressive aquifer depletion and ultimately, permanent aquifer damage.” (GSA)
During the droughts of the 1980’s groundwater levels were reported to drop 50 to 100 feet. Serious droughts occurred in ’81, ’86 and ’88. (Corps ’92)
Moderate drought conditions occur in the watershed on a 13-year cycle. (GSA)
The basin has shown evidence of experiencing prolonged periods of hydrologic drought where improved rainfall allows recovery of agriculture and plant life but does not adequately replenish streams and aquifers.
A significant flood occurred in March 1990 causing severe damage in the urban and rural areas of Elba and Geneva, AL as well as Caryville, FL. Damages were estimated at $88 million. (Corps)
For the Pea River this was the single worst flood in the history of the region, the next largest occurring in March of 1929 and the third largest in July 1994. (Corps and GSA) Studies following the 1990 flood suggested improvements to the levees at Elba and Geneva but did not recommend the construction of a flood control dam on the Choctawhatchee or Pea Rivers.
Water volumes may exceed 100 times the normal low water channel during flood events. (Corps)
The Flood of 1929 ranks as one of the greatest ever experienced in the southeastern US. Rainfall at the center of the storm was 29.6 inches at Elba. (NRCS) The gage height at Newton recorded 42 feet. (GSA)
For further information on Flood Conditions within the basin see NRCS and GSA documents.