Drought in Pennsylvania, May 1 to 31, 2002

Eastern Pennsylvania entered May 2002 with improving weather conditions with respect to the drought, but the drought emergency remained in effect for all of Eastern Pennsylvania with mandatory watering restrictions in place. The Delaware River Basin Commission, which oversees water supply throughout the Delaware River Basin declared a "drought" on December 3, 2001 when the supply of water in the New York City reservoir system dropped below a designated level for early December. The commission declared a drought emergency on December 18, 2001. Both triggered additional reductions in the amount of water released from the reservoirs into the Delaware River and the amount diverted out of the Delaware River Basin to New York City and New Jersey. Diversions to New York City dropped from 800 million gallons a day to 520 million gallons a day. The emergency declaration gave the commission the power to restrict the amount of water suppliers could draw from the basin. It gave the commission the authority to take water from municipal reservoirs to maintain river levels. It could also call for water releases from federal, state and privately owned reservoirs. Water from Lake Nockamixon, the F.E. Walter Reservoir and Lake Wallenpaupack could be used to maintain river levels. Releases from the F.E. Walter Dam were reduced to one-third of normal to save water. They were last used for this purpose in the 1960s. The releases help protect the riverbank and aquatic life and also prevents salt water from flowing up the Delaware River. Salt water intrusion causes corrosion problems for industries and increases water treatment costs for municipalities that depend on the river for their water supply. Maintaining river levels are also important for groundwater reserves that are recharged by the river itself. On May 1st, the salt front along the Delaware River was three miles farther upstream than its normal May position. The emergency declaration also gives the commission the power to request that utilities and other companies that use more than one million gallons of water a day to prepare contingency plans to use less water and submit the plans to the commission. Drought conditions continued to improve during the month of May as precipitation ranged from near normal around the Philadelphia to well above normal in the Poconos. Conditions improved so much that on May 8th Governor Mark Schweiker moved Carbon and Monroe Counties from drought emergency to drought watch status. On a county weighted average May monthly precipitation totals ranged from 4.0 inches in Delaware County to 6.5 inches in Monroe County. Normal is around 4.4 inches. The New York City Reservoirs which feed the Delaware River increased from 62.5 percent of capacity on May 1st to 81.2 percent of capacity on June 1st. Normal for June 1st is 99.5 percent of capacity. For the first time since last October, reservoir storage was within the normal range. Under law, the Delaware River Basin Commission drought emergency declaration could not be lifted until reservoir levels remained 40 billion gallons above the drought watch level for 30 days. This was not achieved as of May 31st. By May 31st though, the salt front on the Delaware River was three miles farther downstream than normal. For the month streamflow on the Delaware, Schuylkill and Lehigh Rivers averaged 150 percent of normal. May total monthly precipitation was 4.41 inches at the Reading Regional Airport, 4.45 inches at the Lehigh Valley International Airport and 3.57 inches at the Philadelphia International Airport.