Green Mountain Foothills

Only 0.70% of Lamoille County is in Moderate Drought (D1) or worse as of September 15-21, with the remainder classified as Abnormally Dry. The minimal drought footprint reflects the region's early-autumn moisture status; this represents no intensification from the prior two weeks, indicating conditions are stable despite the month's precipitation shortfall.

Month-to-date precipitation at Mount Mansfield station is 0.9 in, running 3.5 in below normal for this date. The Lamoille River at Johnson measured 134 cubic feet per second on September 22, near the week's low range but within recent variability. Below-normal rainfall in early fall typically translates to reduced base flow as groundwater recharge lags; this deficit suggests streamflow may continue to run lower than seasonal norms into early October without significant precipitation.

Mayflies were recorded in Jeffersonville on August 31. These pollution-sensitive aquatic insects require well-oxygenated water and are recognized indicators of good water quality, their presence marking functional habitat in the stream.

Canadian burnet, a federally threatened species, was observed on 2026-08-20 in the region. This wetland-associated perennial typically inhabits bogs, swamps, and wet roadsides, making its presence notable during a period of below-normal precipitation that may stress wet habitats.

Susquehana Sandcherry, a federally threatened species, was observed on 2026-09-01 in Chittenden County. The plant occurs in sandy, dry sites typical of its habitat; this observation during a period of moderate drought with 0.70% of Lamoille County in moderate drought conditions may reflect stress on sandy-substrate populations adapted to seasonal drought.

Lamoille County's drought monitor reading shifted this month for the first time since spring. After holding at zero abnormally-dry coverage from late April through late July, 38.65 percent of the county registered as abnormally dry the week of August 4-10 and has held near that level since. That's the mildest category on the drought monitor's scale, and no moderate or worse drought has been declared yet. What makes this worth watching is the shape of last year's calendar. In 2025, the same county saw an almost identical August dry spell that escalated quickly: moderate drought covered the whole county by mid-September, severe drought followed by late September, and extreme drought had spread countywide by mid-October, only easing back to zero this past spring. That history doesn't guarantee a repeat, but it's why a modest August reading here deserves attention rather than a shrug. The timing also lands on top of two other signals already logged from these foothills this summer: an Autumn Meadowhawk dragonfly that emerged four to six weeks early in mid-July, and a threatened Canadian Imperial Moth found near Jeffersonville, a species whose caterpillars depend on the health of pines and spruces already under budworm pressure. None of these on its own proves a single unfolding story, but a fast drought onset following last year's script would add stress to systems in the Green Mountain Foothills that are already showing early or unusual signals this season. Water stress of this kind rarely stays confined to soil moisture readings alone; it compounds with whatever else is already straining a watershed. That's part of the context for a separate, unrelated compliance issue in the watershed: the FAIRFAX facility is currently listed in significant non-compliance, but the record on file shows this is an administrative failure — a missing discharge monitoring report — not a documented pollutant exceedance. There's no evidence of a chemical discharge tied to this status, and nothing here suggests the drought and Fairfax's paperwork lapse are connected. Both are simply part of the same seasonal picture for a watershed that spent last autumn in extreme drought.

Canadian Imperial Moth (Eacles pini) turned up near Jeffersonville in late July—a research-grade record of a species that iNaturalist flags as threatened. This is a large, slow-living silkmoth whose caterpillars depend on healthy pines and spruces; their presence in the foothills is a quiet indicator of suitable conifer forest. The foothills also logged four Spruce Budworm Moth observations from early to mid-July—two at 126 Rice Farm Dr, Jeffersonville and two at separate Vermont locations—a data point worth noting as the species remains a concern across conifer forests in the region. The two moths occupy opposite ecological roles: budworm caterpillars are voracious defoliators that strip needle cover in weeks, while Imperial Moth adults don't feed at all and their caterpillars cycle slowly through conifer stands across years. But their appearance across the same corner of the foothills in the same July window matters. Conifer stands under sustained budworm pressure lose needle density fast, and that stress weakens the very pines and spruces that Imperial Moth caterpillars need to survive and mature.

An Autumn Meadowhawk was recorded along the Lamoille drainage near Jeffersonville on July 17 — four to six weeks ahead of its typical appearance in Vermont. This dragonfly's name reflects its usual ecology: most years, the species peaks from late August through November, flying into the cold when other dragonflies have vanished. To find one in mid-July, in the heat, is to watch a species break from the seasonal calendar it has long kept. Meadowhawks overwinter as eggs in dried pond and marsh beds, and their larval development accelerates with water temperature. The drought-driven warmth that has been stressing brook trout and shrinking stream channels this summer may be compressing the aquatic life stage of these cold-tolerant dragonflies. The implications ripple outward: when phenology shifts this sharply across multiple trophic levels and species, it signals that the watershed's seasonal rhythms — sustained for generations — are reorganizing faster than the ecosystem may accommodate.

Flow in the system feeding Halfmoon Lake dropped to 164 cubic feet per second last week — less than half the rate from just three weeks earlier. For a lake already listed as impaired since 2022 with no remediation plan in place, that timing is precarious. July is when most temperate lakes stratify, separating into warm and cold layers that trap oxygen-hungry bacteria in the murky depths. As that sealed layer consumes the last dissolved oxygen, the window for any recovery narrows sharply. Low inflow during stratification season means less dilution of whatever excess nutrients or contaminants are already in the system — and the impairment cycle tightens. Flow did recover to 320 cfs by mid-July, which helps. Yet the broader picture remains unsettled: the watershed drains 38 facilities with significant discharge violations, many of which remain unresolved. For a lake waiting five years for a cleanup plan, every low-flow spell is a test the ecosystem barely passes.

Streamflow has collapsed to a summer low in just three weeks—a Brook Trout catastrophe in the making. Shallow riffles warm quickly without flow, and fish must abandon feeding grounds for cold spring-fed refuges or die of thermal stress. The lucky ones cluster in pockets of groundwater seepage; the rest perish. Each drought summer compounds the last. Young fish that should be recruiting to the population fail to survive the gauntlet. Over successive years, this reshapes the age structure of the population, leaving fewer year-classes to bridge the winters ahead. What appears as a single dry season is really a ratchet: each pulse tightens the screws on a population already running close to the edge.