Drought has been making headlines recently, with wildfires scorching record-breaking acres, fish struggling to migrate upstream due to low flows, and many regions experiencing their lowest rainfall ever for this time of year. With much of the state now in a Level 3-Critical Drought, we wanted to shed light on the process behind drought declarations, the key decision-makers, and the factors they consider.
Drought does happen in Massachusetts...
Since 1895, when weather-related record-keeping began, Massachusetts has experienced over 50 droughts, varying in intensity and duration. The most recent drought of 2024 is unusual because of its severity, its rapid development, and its occurrence outside of the normal drought season. Usually, drought conditions happen in Massachusetts between May and October. But in 2024, drought conditions began in September and continued through December. Many places in the state saw their lowest rainfall totals ever for October. Unfortunately, climate change means we will experience droughts more frequently and that drought may become less predictable.
What factors determine drought?
Various agencies measure six indices to determine the severity of drought (Precipitation, Streamflow, Groundwater, Lakes and Impoundments, Fire Danger, and Evapotranspiration) and measurements for each are collected across the state over the course of a month (see table). These data are then compared to historic measurements and if the collected data are unusually low compared to past data, the decrease is quantified and assigned a drought severity level. If enough drought indices in a specific region correspond to a certain severity level, that level of drought is assigned to that region.
Who determines drought and how?
The administrative body that determines drought in Massachusetts, the Drought Management Task Force, (DMTF) ensures that drought conditions are recorded for public notification and water conservation. The Task Force, an advisory body chaired by the Massachusetts Executive Office of Energy and Environmental Affairs and the Massachusetts Emergency Management Agency, meets monthly during the main drought season, and more frequently when there are significant drought conditions.
The DMTF’s membership includes 16 state and federal officials, and four public members who report on drought conditions across the state at each meeting. In addition to the agencies that contribute data to the drought indices, reports from other task force members are taken into consideration for drought determinations. Such information may include weather forecasts from the National Weather Service, or drought impact reports from public organizations.
Based on data presented at their meetings, the Task Force determines if drought is occurring, where it is occurring, and the level of severity from 0-4 (see infographic below).
As drought level severity increases, the EOEEA’s suggested restrictions on nonessential outdoor water use and water conservation increase (see table).
The DMTF and climate resilience
Massachusetts has experienced some level of drought in one or more regions eight out of the last ten years. As droughts become more frequent, the DMTF’s work will become more important in the state’s efforts to become climate resilient. The public, municipalities, water suppliers, and others cannot effectively prepare for, or mitigate, drought conditions without timely and science-based determinations resulting from the essential work of the DMTF.
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