Linn Run Conservation Plan Released
Forbes Trail Chapter of Trout Unlimited debuted their final Linn Run study results at a public meeting on March 30, 2023, at the Powdermill Nature Reserve. Thirty-five guests were present to learn about the overall health of Linn Run watershed and what threats to the stream need to be addressed.
The study began in April of 2021 and was funded with a grant from the Foundation for Pennsylvania Watersheds, a grant-making foundation that invests in efforts to protect healthy, natural streams around the state. The study was a “partnership” effort involving state and local agencies and nonprofit organizations, each bringing unique expertise to the table. Nearly fifty volunteers, including TU members, citizen scientists and professional chemists and entomologists worked on the project for nearly two years.
The specific studies looked at the water quality including potential pollutants such as E. coli, iron oxide, road salt and aluminum which can harm all aquatic life. Extensive sampling done for macroinvertebrates (trout bugs), showed that the main stem and the major tributaries all had a healthy variety and number of bugs.
Teams of volunteers conducted habitat assessments looking at every inch of the stream and tributaries from the first raindrop on Laurel Mountain to where Linn Run passes under the Rt. 381 bridge in Rector. Bank erosion from flash floods, hiking trail washouts, log jams and barriers restricting fish movement were some of the problems discovered. The Hemlock Woolly Adelgid (HWA), a tiny insect that infects the needles of hemlock trees, has been documented and could threaten the canopy over nursery waters.
A limestone treatment system installed on the largest tributary, Rock Run, in 2005 has proven to be effective at raising both the pH and alkalinity of the tributary to where it now supports wild trout reproduction. A similar treatment system might be considered for the headwaters of Linn Run.
The Coldwater Conservation Plan is part of a “process”. The next step will be for TU to meet with partners such as the State Park and Forbes State Forest officials to determine what remediation efforts DCNR might be able to work into their budgets and maintenance plans. Then, decide if grants and more manpower might be needed. Some activities such as clearing log jams after severe floods and monitoring for E. coli, the HWA and gill lice is expected to be an ongoing exercise by the partners.
Overall, Linn Run is a relatively healthy, but somewhat fragile, high gradient mountain stream. It and the surrounding park and forest attract well over 100,000 visitors each year. Linn Run is the “crown jewel” of the watershed and the Partners are committed to Conserving, protecting and restoring it using whatever resources are needed.
Rock Run Water Tests March 2023
Monthly Rock Run Water Tests 2-25-23
It was a cold morning as the FTTU citizen scientists conducted monthly pH and alkalinity tests with frozen hands.
We arrived to find even more trees and branches down over the stream.
Air Temp – 28° F
Water Temp – 37.5° F
pH – 7.3
Alkalinity – 3.4
Linn Run Discharge – 21.1 ft³/sec – Medium High
Rock Run Water Tests February 2023
“If a tree falls in the forest, and no-one is there to hear, does it make a sound?”
The answer is “Yes”, and a pretty loud one too when this one came crashing down roots and all across Rock Run, probably during high winds from the storm on 1/25/23.
Results of water tests 1/29/23
Water Temperature: 38.5°
Air Temperature: 38°
Linn Run Gauge: 1.94′
Final Rock Run Water Tests For 2022
FTTU Citizen Scientists wrapped up monthly water tests at the mouth of Rock Run for 2022. After a few months of low water, The flow was at its highest since April. Readings showed pH at 7.4, and Alkalinity at 5.5. Air temperature was 50° and water temperature was 43°. Linn Run gauge was at 2.03 ft. and discharge was 16.3 ft³/sec.
Averages over the 12 months of 2022 were 7.55 pH and 6.85 alkalinity. Alkalinity was down a bit from 2021 but average flow was a little higher. Those two things go hand-in-hand. When flow is up, alkalinity goes down. Overall averages show significant improvement and slow but steady progress since we started doing monthly tests in 2017. Alkalinity that year was 5.9 and pH was 6.47.
The pH and alkalinity chart for 2022 can be seen here – pH Chart 2022
Rock Run Water Tests for November
Water quality tests for November:
Air Temperature: 42° F
Water Temperature: 47.5° F
Linn Run Gauge: 1.46
Linn Run Flow: 1.9 ft³/sec
A splash of rain brought water levels up a bit but alkalinity also went up. Maybe recent addition of limestone has helped.
Rock Run Water Tests For September
Water tests for September were done on Sautrday the 2nd.
Air Temperature: 66° F
Water Temperature: 65° F
Linn Run Gauge: 1.34
Linn Run Discharge: 1.2
Lowest flow of the year.
Stream may look dried up in photo below, but there is flowing water and trout can find refuge in pools.