Area Girl Scouts are learning about stormwater and the potential for environmentally-damaging runoff.

The consequences of stormwater runoff were all too real in the Lehigh Valley after an early-August rainstorm.

Three members of Troop 6810, St. John’s United Church of Christ, Emmaus, attended the Aug. 15 meeting of the Salisbury Township Environmental Advisory Council.

Gerald Mistal, Penn State Master Watershed Steward, taught the Girl Scouts about watershed pollution. Mistal set up a Stormwater Model Enviroscape in the township Municipal Building meeting room.

The Watershed Steward program is run by The Pennsylvania University Extension. It’s an all-volunteer program. A 16-week course is required of participants.

Mistal used substances to represent pollutants and then water to show the effect of stormwater runoff.

Girl Scouts in attendance were Alexa Ebeling, Ginny Shellenberger and Alexia Striano. Also attending were Girl Scout leaders Kelly Ebeling and Traci Shellenberger.

After Mistal taught about the Enviroscape, the Girl Scouts took turns using it. The goal was for the Girl Scouts to be learn how to do presentations for other Girl Scouts.

“It’s basically teaching about point source pollution and nonpoint source pollution,” Mistal told a reporter for The Press after the 45-minute presentation.

According to the web site of The National Oceanic and Atmospheric Administration, an agency in the United States Department of Commerce, the U.S. Environmental Protection Agency (EPA) defines point source pollution as “any single identifiable source of pollution from which pollutants are discharged, such as a pipe, ditch, ship or factory smokestack.” Factories and sewage treatment plants are examples of point sources.

The EPA defines nonpoint source pollution as that “caused by rainfall or snow melt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, depositing them into lakes, rivers, wetlands, coastal waters and ground waters.”

Using the Envirospace, which is a diorama of a town, park area and farm fields, Mistal instructed the Girl Scouts to sprinkle powdered substances representing fertilizer, insecticides and sediment on the surfaces of the model.

‘The No. 1 pollutant is sediment,” Mistal said.

The Girl Scouts used plastic containers to spray water on the diorama surfaces. The substances sprinkled on the model flowed into areas representing a culvert, creek and pond.

“This is what happens when we don’t do the right thing at home,” Mistal said. The philosophy of stormwater management is: “Only rain in the drain.”

“This is what we call a watershed,” Mistal explained. He said that the Monocacy Creek Watershed, the Lehigh River Watershed, the Delaware River Watershed and the Chesapeake Watershed are interconnected.

“It’s all part of the land that the water flows through,” said Mistal.

“We’re all connected,” said Alexia Striano.

The Envirospace represents real-life implications for the Lehigh Valley.

On Aug. 3, an estimated 3 inches of rain is believed to have resulted in the overflow of 9.22 million gallons raw sewage between 4:30 a.m. and 6:30 p.m. Aug. 4 at Kline’s Island Wastewater Treatment Plant into the Little Lehigh Creek, according to the Lehigh County Authority (LCA).

The Little Lehigh provides water for Allentown, parts of Salisbury Township and other municipalities.

A boil-water advisory issued by the Lehigh County Authority Aug. 8 for Upper Macungie and South Whitehall Townships was lifted Aug. 10.

Salisbury Township, along with other Lehigh Valley municipalities, received notice June 25, 2014, to provide the EPA with evidence of MS4 compliance.

Salisbury met conditions of the Administrative Order and Section 308 Requirement for Information of the Clean Water Act issued May 29, 2014, according to an EPA letter received by the township April 14, 2015.

Salisbury’s five-year National Pollutant Discharge Elimination System (NPDES) permit, issued in 2014, is good until early 2019.

Municipalities have spent about $39 million since the order and plan to spend another $31 million to improve storm sewer systems.

According to the LCA, since 2012, Salisbury Township has spent $1.1 million and plans to spend $1.5 million on its 69 miles of storm sewer and Emmaus has spent $1.8 million and plans to spend $1.2 million on its 45 miles of storm sewer.

Required to submit annual reports to the EPA about overflows and repairs are: Lehigh County Authority, City of Allentown, Coplay-Whitehall Sewer Authority, Allentown, the townships of Hanover, Lower Macungie, Lowhill, Salisbury, South Whitehall, Upper Macungie, Upper Milford, and Weisenberg, and the boroughs of Alburtis, Emmaus and Macungie.

Under the federal Clean Water Act, a municipality must have an MS4 storm water management program for stormwater discharges to be in compliance with the permit.

Salisbury Township MS4 Coordinator, Building Code Enforcement Officer, Assistant Zoning Officer and Building Inspector Sandy Nicolo had to meet an Aug. 4 deadline to file information with the Pennsylvania Department of Environmental Protection (DEP) for renewal of the township’s NPDES permit, which expires Feb. 28, 2019.

Nicolo has a Sept. 30 deadline to submit a progress report on the township’s Pollutant Reduction Plan (PRP), for which a public hearing was held June 28.

The DEP requires Salisbury to reduce its sediment load by 10 percent, or 198,354.61 pounds, i.e., about 200,000 pounds, per year.

The goal of the PRP is to reduce debris, soil, cinders, sedimentation, and the like from entering the township’s storm water system and flowing into rivers, creeks and ponds in the township.

And that’s what the Girl Scouts learned about in the Stormwater Model Enviroscape presentation at the township EAC meeting.