Connecticut laws/regulations; Other States laws/regulations; Background;

OLR Research Report

January 11, 2011





By: Kristen L. Miller, Legislative Analyst II

You asked for information about Connecticut's proposed stream flow regulations and whether they are similar to stream flow regulations in other New England states. You also asked about possible impacts that the proposed regulations may have on industry and economic development.


Public Act 05-142 requires the Connecticut Department of Environmental Protection (CT DEP) to revise current water flow regulations, expanding them to include all rivers and streams. The regulations must balance ecological and human needs, and be based on natural water flow variation and the best available science. CT DEP developed proposed regulations establishing four stream classes.

The other New England states all regulate river and stream flow, directly or indirectly. Maine has stream flow regulations for classified state waters. Massachusetts is currently developing stream flow regulations and Rhode Island manages stream flow through water quality rules and permitting. New Hampshire is statutorily required to develop stream flow rules for designated rivers and is conducting a pilot study on two rivers. Vermont monitors stream flow through Water Quality Standards, permitting processes, and snowmaking-specific regulations.

Like Connecticut, the other New England states base river and stream flow restrictions, whether through law, regulation, or policy, on natural flows. Connecticut, Maine, New Hampshire's and Vermont (snowmaking only), regulations are required by legislative mandate. Massachusetts, Rhode Island, and Vermont use other means to monitor river and stream flow, such as water quality standards and permitting. All states strive to balance competing interests of ecological protection and recreational uses with the need for human water consumption.

Businesses, utilities, municipalities, and other organizations have voiced opposition to the proposed Connecticut regulations, which CT DEP revised after a public hearing process. These groups contend that the proposed regulations may increase their water costs, produce water supply shortages, burden industry, and hinder economic development.

CT DEP responds that some necessary changes in water resource management may increase costs. But CT DEP maintains that the regulations contain provisions to minimize fiscal impact and provide compliance flexibility. Increased costs are borne by those who benefit from water use and maintaining water supply is necessary for the state's economic health, CT DEP states.

Connecticut also regulates water diversion through its Water Diversion Policy Act, which this report does not discuss (CGS 22a-365 – 22a-378). Additional information about Connecticut water diversion is available in OLR Reports 2001-R-0345 and 1999-R-0350.


Public Act 05-142 directs CT DEP to develop new stream flow regulations for all rivers and streams. The current regulations cover rivers and streams CT DEP has stocked with fish.

Under prior law, the regulations had to (1) provide for stream and river ecology, aquatic life, wildlife, and public recreation, and (2) be consistent with the needs and requirements of public health, flood control, industry, public utilities, water supply, public safety, agriculture, and other lawful water uses. The act requires that the regulations provide for such needs and requirements and be based on the best available science and, to the greatest extent possible, on natural variations in water flow and water levels. A summary of the act is available at: http://cga.ct.gov/2005/SUM/2005SUM00142-R02SB-01294-SUM.htm

CT DEP held public informational meetings on the proposed regulations. A public hearing was held on January 21, 2010, and the comment period closed on February 4, 2010. CT DEP heard oral testimony from 68 individuals and received 380 written comments. All written comments are available on the CT DEP website at http://www.ct.gov/dep/cwp/view.asp?a=2719&q=434018&depNav_GID=1654. In response, CT DEP revised the proposed regulations and submitted them to the attorney general for review and the Legislative Regulation Review Committee for approval.

On October 26, 2010, the committee acted on the proposed regulations, rejecting them without prejudice and asking DEP to revise them. CTDEP revised the proposed regulations and resubmitted them to the committee on December 7, 2010. The revised proposed regulations were reconsidered by the committee on December 21, 2010 and were rejected without prejudice for a second time.

The Initial Proposed Regulations

The proposed regulations place all rivers and streams into one of four classes based on natural stream flow variation and on existing and planned degrees of human alteration. Each class has different management standards. In Class 1 waters, priority is given to ecological health. The standards for Class 2 and Class 3 waters balance ecological and human interests. The standards for Class 4 waters weigh human interests most greatly.

The regulations establish presumptive (numeric) standards for each class based on seasonal flow criteria and flow altering activity, including specific dam release requirements to maintain minimum flow. Criteria for classification include analyzing existing diversions and dams, return flows, land cover, planned land use, animal and plant species, stream gages, wild and scenic designation, and potential for water supply, among others. The classification process provides opportunity for public input and the regulations contain a procedure to alter classifications, based upon changes in flow pattern and stream or river characteristics. The classification process may take up to five years.

Once a stream is classified, dam operators who regulate stream flow, divert water, or pump large quantities of groundwater from aquifers, must meet certain requirements. Owners or operators of other structures or devices that divert water and impact surface water flow must also minimize stream flow impact. Full compliance is required not later than 10 years after classification, though extensions may be allowed.

The act authorizes CT DEP to provide regulatory exemptions in circumstances of (1) extreme economic hardship, (2) agricultural diversions, (3) water quality certifications in Federal Energy Regulatory Commission (FERC) licenses, and (4) public water systems that need to meet obligations under state regulations.

Other regulatory exemptions from certain requirements include temporary repairs or maintenance, fire emergencies, withdrawal of less than 50,000 gallons in a 24-hour period, diversion pursuant to current diversion permits, and certain dams, among others. Flow management compacts and CT DEP-approved plans tailored to specific watershed needs may be allowed to meet classification goals and the regulations also include provisions for limited-term variances, drought relief, unusual climatic or operational circumstances, and record keeping and reporting.

Revisions to Regulations Subsequent to October 26, 2010 Legislative Regulation Review Committee Meeting

DEP made many revisions to the proposed regulations after the October 26, 2010 Legislative Regulation Review Committee meeting. Some of these revisions include removing the sections pertaining to “other structures” and flow management compacts; specifying dam release requirements instead of presumptive standards; adding exemptions for infrequently-used public water supply dams and owners or operators of dams which divert water for agriculture or golf courses; and adding a margin of safety consideration to the Class 4 narrative standards, among other substantive and technical changes.


Ground and surface water withdrawal is regulated on a state-by-state basis. Stream flow is generally defined as the volume of water flowing in a stream or river at a given point in time. In recent years, New England states have moved toward greater stream flow oversight and regulation, either directly or indirectly.

Stream and River Flow in Other New England States

Like Connecticut, Massachusetts is actively developing stream flow regulations. Maine already sets minimum river and stream flow levels for classified state waters. New Hampshire is conducting a limited stream flow program. Rhode Island does not have specific regulations but monitors stream flow through water quality standards and withdrawal permitting. Vermont addresses stream flow through water quality standards, permit procedures, and a specific stream flow regulation for snowmaking. OLR Report 2006-R-0070 provides additional information on watershed planning and water resource conservation in these states.

Given the time constraints in preparing this report, we provide a brief summary of these state measures below. If you would like, our office would be happy to provide further information on any state's specific program.


In 2002 the Maine legislature established a Sustainable Water Use Policy (38 Me. Rev. Stat. Ann. 470-A—470G). This created the Water Withdrawal Reporting Program and requires reporting water withdrawals beyond threshold levels to the Maine Department of Environmental Protection (ME DEP) (38 Me. Rev. Stat. Ann. 470-B). ME DEP is also statutorily required to establish water use requirements for maintaining stream flows and lake or pond levels (38 Me. Rev. Stat. Ann. 470-H). The statute mandates that requirements be based on natural flow and water level variation.

ME DEP adopted a rule to protect designated uses and aquatic life (Chapter 587). The rule applies to direct or indirect withdrawal, removal, diversion, or other activities altering the natural flow or water levels, with exceptions. Stream flow requirements are based on natural flows, uses, and the characteristics assigned by the water quality classification program (38 Me. Rev. Stat. Ann. 464, 465). Flow is managed by seasonal aquatic base flows or other seasonally variable flows. ME DEP may allow alternative water flows and variances based on site-specific flows. Variances are also permitted for community water systems during drought conditions. All activities altering water flow of classified state rivers that require new or reissued permits are regulated according to the flow requirements. The rules provided a five-year compliance period.


Massachusetts manages water quality and quantity through a combination of statutory, regulatory, and policy-based means. Such standards can be found in the state Water Policy Task Force's 2004 Water Policy, the Wetlands and the Stormwater Policies and Guidances, and Water Management and Interbasin Transfer Acts. For example, the Water Management Act (WMA) (M.G.L. c. 21G) authorizes the Massachusetts Department of Environmental Protection to regulate water withdrawn from surface and groundwater. The purpose of the regulations promulgated under WMA (310 CMR 36.00) is to manage surface and groundwater as a single hydrologic system balancing competing water uses.

In 2003, the Massachusetts Water Resources Commission directed its staff to develop stream flow policy. As a result, the Massachusetts Department of Conservation and Development developed 2008 Index Streamflows intending to show the range of natural stream flow conditions expected in undisturbed streams. Massachusetts is using an inter-agency approach to protect and manage water resources. A state Sustainable Water Management Initiative is developing stream flow regulations and answers to other water needs, while considering ecological and environmental concerns. Stream flow regulations are currently being drafted and discussed.

New Hampshire

In the late 1980s, the New Hampshire legislature established statutory protections for certain designated rivers based on natural and cultural resources. The protections included requiring that the state regulate protected steam flow levels for designated rivers and segments (N.H. Rev. Stat. 483:1 et seq.). The statute provides river classification criteria for designated rivers and segments and requires protected stream flows to be maintained at all times, unless exempt (N.H. Rev. Stat. 483:9-c(IV)).

In 2002, legislation created the Instream Flow Pilot Program applicable to the Souhegan and Lamprey rivers to develop river-specific numerical criteria for stream flow protection, and water management plans to implement the criteria. The New Hampshire Department of Environmental Services adopted Instream Flow Rules applicable to the pilot study rivers. The rules include procedures for determining and administering protected stream flows and water management plans. Protected stream flows are determined through conducting flow studies of the designated rivers. If successful, the Instream Flow Rules will be amended before applied to other designated rivers.

New Hampshire also manages water resources through the water use registration and reporting program. The program collects data on major water uses and demands on aquifers, rivers, and streams. In 2003 the legislature established new water conservation standards for new

sources of groundwater for community systems, new water sources for bulk and bottled water operations, new large groundwater withdrawals, and new surface water withdrawals requiring water quality certification, among other things (N.H. Rev. Stat. 485:61).

Rhode Island

The Rhode Island Water Resources Board (Board) was established to develop the state's water allocation system (R.I. General Laws 46-15 et seq.). It is responsible for ensuring availability of sufficient water resources and has sole authority to allocate water resources. Rhode Island's Water Quality Regulations provide water quality standards that include maintaining a quantity necessary to protect ecological and human needs. The standards are applicable to activities altering water flow. Flow conditions must support existing and designated uses. Water diversion is also overseen during permitting. The Office of Water Resources uses a Streamflow Depletion Methodology to determine the allowable amount of water extractable from a stream leaving sufficient flow to maintain a healthy aquatic habitat and ecosystem. This methodology is applied to all new or increased water diversions.

In 2002, the Board created the Water Allocation Program Advisory Committee which established a Streamflow Subcommittee responsible for developing stream flow standards. In 2004, the subcommittee published its final report, which recommended watershed specific flow protocol as the preferred approach for state stream flow standards. Stream flow regulations have not been proposed but the state is preparing to introduce water conservation-based regulations.

Resources Primer


Vermont generally manages stream flow through its Water Quality Standards' (WQS) Hydrology Policy (Vt. Code R. 12 004 052), an agency stream flow procedure applicable to most activities, and snowmaking-specific regulations to maintain conservation flow. WQS goals are obtained in part by promoting water conservation and proper management of water resources.

Under WQS' hydrology criteria, deviations from a water's natural flow regime are regulated and, for some waters, the state may impose specific hydrologic standards (Vt. Code R. 12 004 052, 3.01(C)(1)).

Further, water withdrawal from lakes and streams usually requires permitting and the Vermont Agency of Natural Resources determines acceptable minimum stream flows necessary to meet WQS requirements. The procedure provides that, generally, minimum flows adequate to maintain fishery interests are sufficient to maintain acceptable water quality and recreational uses. It accepts the U.S. Fish and Wildlife Service recommended minimum flows and presumes these flows protect stream flow and use. Lower conservation flows may be approved if applicants conduct site-specific studies.


Connecticut's proposed regulations must balance ecological and human needs (CGS 26-141b).

Arguments Against Proposed Regulations

Businesses are concerned that costly requirements could disrupt their operations and harm economic development by limiting growth for new and existing businesses. They argue that the regulations add an additional layer of regulatory control which could negatively affect Connecticut's marketability to outside industry. There is concern that this could slow the state's economic recovery because a delay in classifying rivers and streams may leave businesses without guidance as to future water restrictions and compliance requirements.

Businesses, utilities, municipalities, and other organizations contend that the proposed regulations may increase water cost, produce water supply shortages, burden existing industry, and hinder economic development.

Comments made during the public hearing process and after CT DEP's revisions to the regulations indicate concern that the regulations will increase costs to suppliers. Some maintain that the regulations impose an unfunded mandate on municipalities served by municipal water departments. Others contend that increased costs may result from construction or modifications to infrastructure, compliance reporting requirements, lost investment in existing infrastructure, development of new water supplies, and additional operating cost and staff time for determining required releases and making adjustments. Increased supplier costs could result in ratepayer increases.

There is also concern that the regulations will limit available water supplies. This may restrict the ability to meet customer needs, particularly in summer months, resulting in use restrictions or moratoriums on construction and development. Opponents are concerned that reducing existing water supplies will reduce margins of safety for public water supplies, reduce new customer hook-ups, impose more frequent and lengthy use restrictions, and require development of new water sources.

Arguments for Proposed Regulations

CT DEP concedes in its August 16, 2010 hearing report that changes in water resource management are necessary to comply with the statute, and may include infrastructure investment and new operating requirements. But CT DEP maintains that the regulations reduce fiscal impact through exemptions and variances, flow management compacts, margin of safety time extensions and a long implementation schedule, and allowing companies to consider infrastructure upgrades as part of long-term planning. Operators of structures or devices that divert water, except dams, are also only required to minimize impact on stream flow and act in an environmentally responsible manner. Low interest loans or grants from the Drinking Water State Revolving Fund may be available to offset water utility costs.

The hearing report states that the benefit to water consumers is a high quality water supply which also benefits the environment. CT DEP maintains that (1) increased water costs will be paid from those who benefit from resource use, (2) healthy rivers are an economic benefit, and (3) the regulations ensure current and future water supply availability. CT DEP states that maintaining an environmentally sustainable water supply is essential to Connecticut's economic health and will help the state grow in an environmentally sustainable manner.