Sunday, September 12, 2010

Stream Flow Regulations in CT - DEP Final Rule

The Connecticut Department of Environmental Protection (DEP) has released final proposed stream flow regulations that respond to public comment on an initial draft. The final proposed stream flow regulations must be approved by the General Assembly’s Regulations Review Committee before they can take effect.

DEP proposed the stream flow regulations in response to requirements in legislation approved by the General Assembly and signed into law by the Governor in 2005 (PA 05-142). This law directed the agency to develop regulations that would expand the coverage of existing minimum stream flow standards to include all rivers and streams, rather than only those stocked with fish as was previously the case. It also directed DEP to develop standards that allowed the state to meet human needs for water while preserving and protecting aquatic life, fish and wildlife that are dependent on the flow of rivers and streams.

DEP issued draft proposed stream flow regulations on Oct. 13, 2009. The agency held two public information sessions on this draft, held a formal public hearing Jan. 2010 and accepted public comment. Based on public comment on the initial draft regulations, five themes were established to guide the development of the final proposed regulations. An overview of the most significant changes from the initial draft regulations in October 2009 shows that the final proposed regulations:

Double the timeframe for compliance, from 5 to 10 years, for rules governing releases from dams
• Simplify rules governing releases from dams
• Streamline requirements governing groundwater to focus on diversions that are determined to contribute to the low flow of rivers

The regulations establish four categories, or classes, of rivers and establish management standards for each category. The process for classifying streams includes public input and consultation with the Department of Public Health. The key considerations for determining the class appropriate to specific waters are detailed in the regulations. The categories of rivers and streams are:
Class 1 waters are considered “natural,” characterized as a resource having little current development in the watershed and having not been affected by the removal of water for human uses.
Class 2 waters are considered “near natural,” sharing many characteristics with Class 1 systems. The flow standards for this class, however, allow for some levels of human alteration.
Class 3 waters are defined as “working rivers,” where human uses may have an influence on steam flow patterns. These rivers and streams are expected to have adequate water resources available to support viable aquatic communities. Some changes in use may be necessary to restore flow patterns needed to ensure these conditions.
Class 4 waters are characterized as systems where past practices have resulted in a significant deviation from the natural stream flow pattern and restoring these rivers and streams to a natural condition would be impractical. In order to prevent additional water quantity degradation, the regulations now require the use of “best management practices” in the taking of water along Class 4 rivers.


In Class 1 waters, priority would be given to protecting the ecological health of a river or stream. In Class 4 waters, support of human activities would be weighted most heavily. In Class 2 and Class 3 waters, activities would strike a balance between ecological and human needs.

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