Flood in Pennsylvania, June 20 to 21, 2003

A slow moving low pressure system at both the surface and aloft helped trigger very heavy rain across Chester County from the late morning into the afternoon 20th. Storm totals averaged between 2.0 and 5.0 inches, most of which fell during the afternoon at the rate of half an inch to inch per hour. The heavy rain led to widespread poor drainage flooding as well as flooding of most of the gaged rivers and streams in the county. The worst flooding occurred in and around Downingtown along the East Branch of the Brandywine Creek and the Beaver Creek. All roads leading into and out of Downingtown were flooded. The borough was blockaded by flood waters. Gas and electricity was cut to about 40 homes until flood waters receded shortly after midnight EDT on the 21st. Sand bags were used to block the creek from homes. The East Branch of the Brandywine expanded to five times its normal width. Benches in parks were swept away and several homes were flooded. Diesel fuel also spilled into the creek. Elsewhere in the county, flooding was reported in all low lying areas. In Kennett Square Borough, flooding along the East Branch of the Red Clay Creek closed South Street. In West Chester Borough, Goose Creek overflowed and blocked several roads after 4 p.m. EDT on the 20th. Several people were rescued from vehicles. In East Bradford Township, U.S. Route 322 and Pennsylvania State Route 162 were closed along the East Branch of the Brandywine. In Pocopson Township, Street Road and Pennsylvania State Route 100 became part of the Brandywine Creek. A roof collapse in East Goshen Township was the only rain related injury. One person was lacerated. The water saturated soil, mudslides and the general flooding caused trees to fall. About 29,000 PECO Energy customers lost power. The East Branch of the Brandywine Creek in Downingtown was above its 7 foot flood stage from 527 p.m. EDT on the 20th through 807 a.m. EDT on the 21st. It crested at 13.22 feet at 1105 p.m. EDT on the 20th. The West Branch of the Brandywine Creek at Honey Brook was above its 7 foot flood stage from 657 p.m. EDT on the 20th through 533 a.m. EDT on the 21st. It crested at 10.03 feet at 1015 p.m. EDT on the 20th. Farther downstream the creek in Coatesville was above its 7 foot flood stage from 725 p.m. EDT on the 20th through 627 a.m. EDT on the 21st. It crested at 7.75 feet at 3 a.m. EDT on the 21st. In Modena, the creek was above its 9 foot flood stage from 303 a.m. EDT through 434 a.m. EDT on the 21st. It crested at 9.15 feet at 4 a.m. EDT. Along the main stem of the Brandywine Creek along the county border with Delaware County at Chadds Ford, it was above its 9 foot flood stage from 555 p.m. EDT on the 20th through 1003 p.m. EDT on the 21st. It crested at 12.82 feet at 457 a.m. EDT on the 21st. The French Creek at Phoenixville was above its 9 foot flood stage from 533 p.m. EDT on the 20th through 1145 a.m. EDT on the 21st. It crested at 10.99 feet at midnight EDT on the 21st. The Valley Creek at Valley Forge was above its 7 foot flood stage from 358 p.m. EDT on the 20th through midnight EDT on the 21st. It crested at 8.91 feet at 8 p.m. EDT on the 20th. Storm totals included 5.36 inches in West Chester, 4.47 inches in Downingtown, 3.70 inches in Honey Brook, 3.09 inches in Glenmoore, 3.03 inches in Thorndale, 2.75 inches in Sanatoga, 2.35 inches in Exton and 1.86 inches in Glenmoore. The low pressure system responsible for the heavy rain formed along a stationary front over the Carolinas during the morning of the 20th. It moved to just east of Wallops Island, Virginia during the evening of the 20th and well east of the Delmarva Peninsula during the morning of the 21st. An inverted trough at the surface that extended from the low north into Chesapeake Bay and Eastern Pennsylvania concentrated the heavy rain along its axis. June as a whole was an unseasonably wet month. On a county weighted average, June monthly precipitation totals averaged 9.7 inches in Chester County. Normal is around 3.7 inches. The June monthly precipitation total of 8.08 inches at the Philadelphia International Airport was the second wettest on record. The wet spring weather led to a whole different set of problems from the drought of the previous year. Planted seeds were drowning and rotting. Many soybean, corn and berry fields were too wet. There were also problems with slugs. Vegetables were generally about a month behind. Double crop fields fell behind schedule because of the slow growth of straw and hay. Garden shops sales have been down. Pool installations were about three to six weeks behind. Ant infestations increased. Windshield wipers were tearing. Many spring athletic seasons were extended because of postponed events. There will be a bumper crop of mosquitoes. Attendance along the shore and at amusement parks was down. Road work was delayed. The one few positives from the wet weather was lower utility bills.