As Georgia starts its fourth year of drought and summer nears, dry conditions are expected to worsen. After a very wet March that brought temporary relief to topsoil moisture and stream flows, dry conditions have returned to the state.
Since April 1, the entire state has received very little rain. Rain deficits since April 1 include 4.39 inches at Athens, 3.18 at Atlanta, 3.14 at Augusta (Bush Field), 3.76 at Columbus, 0.87 at Macon and 4.20 at Savannah.
Because of the rain deficit, soils have quickly dried across the state. The Georgia Agricultural Statistics Service reports that soil moisture is short to very short in 82 percent of the state’s soils.
In the past six weeks, moisture losses from soils include 5.56 inches at Alma, 7.02 at Brunswick, 7.25 at Savannah, 6.27 at Midville, 5.03 at Plains, 6.64 at Tifton, 5.35 at Fort Valley, 4.30 at Griffin, 3.73 at Watkinsville, 4.60 at Dallas, 4.80 at Gainesvile, 3.91 at Blairsville and 4.06 at LaFayette.
The decrease in soil moisture is stressing pastures and row crops. GASS reports that only one-third of the corn, cotton and hay crops are in good to excellent conditions.
Many farmers are having to irrigate just to get the crops started. Row-crop planting has slowed due to the dry conditions.
Stream flows are extremely low, with daily low-flow records being set on the St. Mary’s River in Charlton County, Little River in Wilkes and Taliaferro counties, Broad River in Elbert and Wilkes counties and Chattooga River in Rabun County.
Flow rates in other unregulated rivers and creeks across the state are near or below the 10 percentile. At the 10th percentile, in only one out of 10 years would stream flows be less than the current flows.
The low stream flows in coastal Georgia are not good news for the shrimping and crabbing industries. Low stream-flow levels in southeast Georgia are associated with decreased white shrimp and blue crab landings.
The dry conditions are also increasing wildfires, with several new fires during the past few days. On May 16, the Georgia Forestry Commission rated wildfire danger as high to extreme over most of the state.
The outlook for breaking the drought is not promising. Even with normal weather, the soils across the state will continue to lose moisture. Normal summer weather also means that streams and reservoir levels will continue to drop.
From May through October, soil moisture loss due to evaporation and transpiration (plant water use) is generally greater than rainfall.
Tropical weather is usually the only event that can cause rainfall to be greater than soil moisture loss during Georgia’s summers. With the extremely dry conditions of the state’s sub-soils, even a tropical storm will probably not break the drought.
With early indications that the summer will be hotter than normal, soil-moisture loss due to evaporation and transpiration may be greater than normal. This increase in soil-moisture loss will tend to increase the severity of the drought.
Daily updated drought information from the University of Georgia is available at www.georgiadrought.org. Daily updated weather information is available from UGA Engineering’s Georgia Environmental Monitoring Network at www.griffin.peachnet.edu/bae/.