Stockbridge Bowl Stewardship Committee Hears Stable 2025 Water Quality Report, Eyes Monitoring Cuts

LENOX — March 26, 2026 — Stockbridge Bowl Stewardship Committee hears that 2025 brought stable water quality but persistent deep-layer bloom risk. Dr. Ben Burpee, senior limnologist with GZA GeoEnvironmental, told the committee at its March 26 meeting that no surface cyanobacteria blooms of significance occurred in 2025, though samples at seven to 10 meters recorded nearly a quarter million cells per milliliter of Planktothrix — the same species identified in the August 2018 lake-wide bloom. Burpee attributed the lake's continued resilience to the absence of severe wind or rain events capable of driving that deep layer to the surface, explaining that "in 2018, I think we had a high-wind event — you even had tornadoes reported in western Massachusetts — it brings all of those deep-growing cyanobacteria up to the surface." Internal phosphorus and iron loading from anoxic bottom sediments remains the bowl's primary management concern, not external watershed inputs, which Burpee said showed consistently high water quality across all three monitored tributary streams. The committee informally accepted a streamlined 2026 monitoring program that cuts GZA on-site field visits from three times annually to twice, reduces chemistry sampling to three depths instead of five, drops routine tributary monitoring, and eliminates several now-redundant chemistry parameters including alkalinity and total Kjeldahl nitrogen. Mike Buffoni, Stockbridge water superintendent and the program's on-the-water field lead, said the Tri-Town Board of Health's newly acquired algae meter now allows near-instant cyanobacteria screening at the treatment plant.