DPW Releases Q3 2026 Drinking Water Supply Updates for the Portsmouth and Pease Tradeport Water Systems
October 16, 2026
The City of Portsmouth’s water supply sources have continued to perform reliably despite ongoing drought conditions that began in June 2025. The Seacoast region currently remains in an Abnormally Dry (D0) classification, with a small portion of the area still experiencing Moderate Drought (D1) conditions. While groundwater levels remain below typical seasonal averages, storage in the Bellamy Reservoir has remained stable and sufficient through 2026.
To support long-term water supply sustainability, treatment operations continue to maximize the use of available surface water from the Bellamy Reservoir, allowing local groundwater aquifers the opportunity to recover during precipitation events. During the third quarter of 2026, approximately 71 percent of the City’s total water supply was provided by treated surface water from the reservoir.
Precipitation patterns during the quarter were below average apart from September. Rainfall totals in July and August were 50 percent and 38 percent below the 10-year average, respectively. However, September rainfall was 28 percent above average, with a total accumulation of 4.2 inches. This significant rainfall helped reduce drought conditions and stabilize source water levels that occurred throughout the high-demand summer season.
While current conditions are stable, ongoing drought conditions could require additional conservation measures if groundwater supply levels decline further. Should the region reenter Severe Drought (D2) conditions more broadly, or if source water supplies become significantly impacted, the City may implement mandatory water use restrictions to help ensure an adequate and reliable water supply for essential needs and fire protection. The City of Portsmouth, in coordination with state officials, neighboring public water systems, and the Seacoast Drinking Water Commission, will continue to monitor conditions closely and provide timely updates to keep water users informed of any changes to drought status or water use requirements.
