Code of Massachusetts Regulations
310 CMR - DEPARTMENT OF ENVIRONMENTAL PROTECTION
Title 310 CMR 36.00 - Massachusetts Water Resources Management Program
Section 36.13 - Safe Yield
Current through Register 1531, September 27, 2024
(1) Safe yield of a water source is calculated as 55% of the drought basin yield plus the reservoir storage volume, if any, for that water source. For the purposes of calculating safe yield:
(2) Should registered volumes for a water source, taking into account any determinations made by the Department pursuant to 310 CMR 36.27(4), exceed safe yield, no additional volumes of water will be available through permitting. Where such registered volumes do not exceed safe yield there is no presumption that withdrawals will be permitted. The allocation of water available for permitting within the safe yield will be determined, and may be limited by, application of streamflow criteria, statutory and regulatory requirements, and site-specific considerations pursuant to M.G.L. c. 21G and 310 CMR 36.00.
(3) Safe yield, reservoir storage volume(s), total registered volumes and currently permitted volumes for each water source will be published on the Department's website.
(4) In a water source where reservoir storage volume is a factor in determining safe yield, reservoir storage volumes are available only to those permittees with legal access to the reservoir(s).
(5) For water sources where an estimate of near natural annualized Q90 streamflow is not applicable because the water source is groundwater-driven (the southern portion of South Coastal, Cape Cod, Islands, and portions of Buzzards Bay), safe yield is determined through analysis of water available during the probable driest period through groundwater recharge for each water source.