Rock Run Water Tests 12.2.23
Recent rains have pumped up the volume of Rock Run on this Saturday, the final water test of 2023.
Air Temp – 53° F
Water Temp – 45.5° F
pH – 6.9
Alkalinity – 6.1
Linn Run Discharge – 16.1 ft³/sec
Linn Run Gauge Height – 1.98′
pH and alkalinity averages are down slightly from 2022, but considering a pH reading of 4.7 was recorded at this loctation in 2005 we can rest assured our limestone sand project has had a overall positive impact on the stream.
Rock Run Water Tests 9.30.23
Here’s the results of water tests at the mouth of Rock Run.
Air Temperature: 59°F
Water Temperature: 56.5°F
Linn Run Gauge: 1.64′
Linn Run Discharge: 3.68 ft.³/sec
The streams had decent flow, but we could use some rain to allow trout to move upstream to spawn.
Rock Run Water Tests 7.29.23
Citizen Scientists were met with a downpour for monthly water tests at the mouth of Rock Run on July 29. The (much welcome) rain forced a quick sample collection and tests conducted in the pavilion at Adams Falls.
Air Temperature: 68°F
Water Temperature: 63.5°F
Linn Run Gauge: 1.85′
Linn Run Flow: 9.65 ft³/sec
Despite the hottest day of summer on the previous day, Rock Run flows at a trout healthy 63.5 degrees.
Rock Run Water Tests for July 2023
The testers were greeted with heavy rain on the morning of July 1, but the skies soon cleared and they were able to conduct monthly water tests at the mouth of Rock Run.
The storm raised water levels from 1.9′ to 2.0′ in less than an hour and with additional rain later in the day peaked at 3.93′ with a flow rate of 565 ft.3/sec at 9:30 pm.
Here’s the test results as of 10:30 am, Saturday, July 1:
Air Temperature: 65°F
Water Temperature: 59.5°F
Linn Run Gauge: 2.0′
Linn Run Discharge: 13 ft³./sec
Alkalinity was surprisingly good considering the influx of rain water.
Afterwards, we went up to the headwaters and checked on the limestone sand that was placed in the stream last year.
It is estimated that 90% has been washed down into the stream. We shoveled the remaining sand in closer to the water.
Rock Run Water Tests For June
Monthly water tests were conducted at the mouth of Rock Run on Saturday, June 3.
Water Temperature – 57.5°F
Air Temperature – 66°F
pH – 7.2
Alkalinity – 6.1
Linn Run Gauge – 1.65′
Linn Run Discharge – 3.54 ft³/sec
Hot, dry weather has come early to the Laurel Highlands this year, however, there was a lower flow recorded in June of 2020 when the Linn Run gauge was at 1.42′. Some rain would be nice though.
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.