Definitions

7Q10, or a Seven-day Ten-year Flow. The lowest seven consecutive day average flow that occurs (on average) once every ten years. 95% Exceedance Flow. A low flow condition in a stream that is exceeded 95% of the time, using a minimum of a ten year period of record. This statistic is based on mean daily flows. Commission. The Massachusetts Water Resources Commission, or the Water Resources Commission staff, as appropriate. Contingency Plan. A written plan establishing operating procedures for adequately handling water supply emergencies, such as contamination of water supply sources or seasonal or drought related shortages of water supply. The plan shall include provision for emergency supply in the event of a sudden loss of existing sources and of a progressively stringent schedule for limiting water use during seasonal and extended dry periods. Decision. A majority roll call vote of the Commission at a public meeting to take action on any matter relating to its duties pursuant to M.G.L. c. 21, §§ 8B through 8D. Donor Basin. The basin from which the water or wastewater is transferred. Drought Year Inflow. A flow calculated from the 90th percentile of estimated near natural daily flows into a water body for each month of the year (monthly Q90), which are then multiplied by the number of days in each respective month and summed for an annual flow. (MA REG. # 1361, Dated 3-23-18) EEA. The Massachusetts Executive Office of Energy and Environmental Affairs. Emergency Connection. Any connection, either approved under M.G.L. c. 21G, §§ 15 and 1616, 310 CMR 36.40 through 36.42 or authorized by law to provide a necessary and adequate water supply during any situation or event, natural or man-made, which causes or threatens to cause damage to a water supply system that could disrupt normal water supply functions. These connections could include interconnections to other existing public water supply systems, connections to obtain water directly from a new source, or connections to obtain greater amounts of water from an existing source than currently authorized under M.G.L. c. 21, §§ 8B through 8D. Hydraulic Capacity. The maximum daily amount of water or wastewater that can pass through an existing authorized Transfer System. Insignificant or Insignificance. An increase in an Interbasin Transfer that has been determined by the Commission, based upon the impact to the Donor Basin, as insufficient to invoke the provisions of M.G.L. c. 21, §§ 8B through 8D, provided that in no case shall insignificance or insignificant mean an increase of one million gallons per day or more. Interbasin Transfer. Any transfer of the surface water, groundwater, and/or wastewater, of the Commonwealth outside of its River Basin as defined in 313 CMR 4.03. As such, the development of a local water supply source to be used within a community, but subsequently discharged as wastewater outside of that community and the source's basin of origin, constitutes an Interbasin Transfer. If a city or town partially situated within a River Basin takes waters from that basin, then the extension of its water or wastewater services to a portion of the same city or town outside the basin shall not be deemed an Interbasin Transfer. MEPA. The Massachusetts Environmental Policy Act (M.G.L. c. 30, §§ 61 and 62 through 62H). MEPA Compliance. Fulfilling the requirements of M.G. L. c. 30, §§ 61 and 62 through 62H, and 301 CMR 11.00: MEPA Regulations. Massachusetts Water Conservation Standards. Measures approved by the Commission that set statewide goals and provide guidance for water conservation and efficiency. Metering. The installation of water use measuring devices on all permanent water supply services, including master meters, source meters, treatment plant meters and purchased water meters. NPDES. National Pollutant Discharge Elimination System. Person. Any agency, the federal government, the Commonwealth (or political subdivision thereof), any state, public or private corporation or authority, individual, trust firm, joint stock company, partnership, association, or other entity, and any officer, employee or agent of said person, and any group of said persons. Present Rate of Interbasin Transfer. The Hydraulic Capacity of a Transfer Facility or Transfer System which was authorized, constructed or useable without additional installation of facilities or changes in any authority or operating rule prior to March 8, 1984. The present rate shall also include: (a) the Hydraulic Capacity of Transfer Systems which, although not fully constructed and/or useable, had achieved MEPA Compliance and final design approval by the Department of Environmental Protection under the provisions of M.G.L. c. 111, as of March 8, 1984; (b) the Hydraulic Capacity of a transfer system found to be Insignificant or approved by the Commission through the process outlined in 313 CMR 4.08, and 4.10, after March 8, 1984; and (c) a legally binding contract that limits the use of the full Hydraulic Capacity of the system. If withdrawal constraints contained in any provision of the Massachusetts General Laws, Special Acts, Judicial Decree, regulatory agency rule, contract or operating rule of a water supplier prevented the use of the Hydraulic Capacity as of March 8, 1984, the lesser amount shall be deemed the Present Rate of Interbasin Transfer. In calculating the Present Rate of Interbasin Transfer for a wastewater conveyance system, said rate includes that amount of wastewater generated from a water supply source within the River Basin from which the wastewater will be transferred. Rate Structure. The pricing system by which water and sewer services are charged to the user. Receiving Area. The location where compliance is evaluated under M.G.L. c. 21, §§ 8B through 8D by 313 CMR 4.09(3)(b) Criterion (2) related to Viable Sources, 4.09(3)(c) Criterion (3) related to water conservation measures, and 4.09(3)(d) Criterion (4) related to a comprehensive forestry management program. For transfers of water supply, Receiving Area means the area into which the water is transferred for use, and is thereby receiving the water supply service. For transfers of wastewater, Receiving Area means the area whose wastewater is collected for discharge out of basin, and is thereby receiving the wastewater service. Regional Water Supply System. For the purposes of 313 CMR 4.00, means a water supply system that serves or proposes to serve two or more municipalities of public water systems outside the Donor Basin. River Basin. A geographic area within the Commonwealth determined by a body of water and its surrounding drainage area as described in 313 CMR 4.03 and as shown in the River Basin Map at 313 CMR 4.13. For purposes of hydrologic calculations, contributing upstream drainage areas, including those outside the Commonwealth, may be considered. The Commission, upon request or by its own action, shall make a written determination of the precise location of the boundary line of the River Basins described in 313 CMR 4.00. In making this determination, the Commission shall consult the report Hydrologic Characteristics of Massachusetts Streams published as a cooperative project by the U.S. Geological Survey and the Massachusetts Water Resources Commission, and other such reports or studies as may be pertinent. River Basin Map. The map or maps of the Commonwealth showing the boundaries of the River Basins. Transfer Facilities or Transfer Systems. Those structures including pumps, pipelines, tunnels, valves, and other conveyance facilities, that facilitate the movement of water or wastewater from one basin to another and across a town line. A Transfer Facility or System can also include a source of water supply which is ultimately transferred out of basin as wastewater. Viable Source. A water source or wastewater service alternative that meets the current regulatory requirements of the permitting authorities, and is environmentally sound, technologically feasible and cost-effective. For wastewater transfers, including those triggered by the development of local water supplies that are transferred out of basin as wastewater, Viable Source includes alternatives which can treat, reuse, and/or discharge wastewater within the basin of origin, and can meet the requirements for approval by the Department of Environmental Protection or other regulatory agency. For water supply transfers, Viable Source means a source which can provide drinking water that meets the current water quality standards and water management requirements promulgated by the Department of Environmental Protection or other regulatory agency, and which can be used while preserving reasonable instream flow using the same criteria provided to evaluate impacts on the Donor Basin listed in 313 CMR 4.09(3)(e).