on the Upper Connecticut River of New Hampshire & Vermont

...proceedings of a conference held by the Connecticut River Joint Commissions, June 1999


The subject of river flow is commanding increased attention from water policy makers, citizens, and businesses engaged in varying ways with America's rivers. Flow is the muscle of a river that turns generators, provides habitat, renews biological life, but can destroy it too in a flood or a drought. As citizens and agencies strive to improve water quality, and as scientists strive to understand riverine systems, the subject of flow - - and flow management - - becomes an important part of the equation. For the Upper Connecticut River, several developments prompted the Connecticut River Joint Commissions (CRJC) of New Hampshire and Vermont to call a regional conference on flow policy in June, 1999.

For the last decade, the NH Department of Environmental Services and the Rivers Management Advisory Committee have been working to develop a state policy on instream flows for all rivers included in the NH Rivers Management and Protection Program. Once the policy's rules are enacted, it will set "trigger" low flow levels to allocate water among the various users in times of drought. The Connecticut is the largest of these rivers. While the Connecticut River is not an important source of drinking water as is the Merrimack River, for example, its flows are imperative for hydropower production and waste assimilation, as well as for the health of its fisheries. The discussions and debates surrounding the development of this state policy have impressed on Connecticut River watchers the importance of understanding the spectrum of uses and values associated with river flow.

The waters of the Connecticut River are under the jurisdiction of the State of New Hampshire up to the historic ordinary low water mark on the Vermont shore. Where the state line is flooded by impoundments, Vermont also shares jurisdiction. Because the Connecticut is a shared river, there may be inconsistencies between the policies of Vermont and New Hampshire which need to be addressed. Among them is the question of how Vermont will provide flow management and water use regulation consistent with New Hampshire's instream flow rules, once they are in effect.

The Connecticut River Corridor Management Plan, published by CRJC in 1997, focused attention on the need for a coordinated approach to flow management, and identified a constellation of river uses and values which depend upon the flow of the Connecticut River. People use the river for swimming, boating, fishing, irrigation, power production, industrial water supply, and waste assimilation. Creatures use it for habitat and migration. Sometimes these uses can compete with one another and in the past, when the river was heavily polluted and far less attractive for recreation, industrial uses often superseded others. This competition between users was one of the reasons why the Connecticut River Joint Commissions worked with the people of the valley to nominate the river into the New Hampshire Rivers Management and Protection Program in 1991 and to develop the River Corridor Management Plan under the provisions of that law.

The river flowing between the two states warrants cooperative management by those states, enabled by the federal government and facilitated by the CRJC as coordinators of such policy within the valley. In the 1997 corridor plan, CRJC recommended that:

  • any flow policies developed for the Connecticut River must maintain water flows at levels which will support the full range of its uses and values, and that
  • New Hampshire and Vermont should cooperate on an ongoing basis in managing the Connecticut River and have coordinated policies on flow management and water withdrawals.

In order to identify the status and implications of flow policies for the upper Connecticut River, the CRJC sponsored a study in 1998 by hydrologist Kathy Fallon Lambert, with support from the Environmental Protection Agency. The report, Instream Flow Uses, Values, and Policies in the Upper Connecticut River Watershed, identified state and federal policies and regulations that affect flows, and recommended opportunities for cooperation and policy development.

As a consequence of the Lambert report, the CRJC worked with a team of federal, state, and local experts to hold a Flow Policy Conference for the Upper Connecticut River Watershed to discuss how policy and coordination could be improved. Gathering in Fairlee, Vermont in June, 1999 were more than seventy representatives of federal and state agencies and the public and private organizations which are directly involved in management and decisions regarding the river.


The Significance of Flow Policies to the Upper Connecticut River

Connecticut River Commissioner Peter Richardson opened the conference with an overview of the forces that influence river flows, and traced the increasing influence of human actions such as deforestation, impoundment, and urbanization upon the Connecticut River. He noted how different policy is today from what it was a century ago, and pointed out that activities that altered the river's hydrology, such as clearing land in the previous century for agriculture, were based on legitimate human needs. "Flow integrates natural events, human activities, and wildlife habitat, but flow that is good for one is not necessarily good for the others."

Mr. Richardson identified recent events with significant implications for flow policy: deregulation of the electric power industry, relicensing of the dams at Fifteen Mile Falls, revision of the Vermont Water Quality Standards, development of the New Hampshire Flow Rules, and master planning for the Corps of Engineers' flood control dams. Decades of research have also contributed to a wider understanding of the relationship of flow to healthy biota. He called for more shared understanding of river systems and interactions with our society, and proposed a memorandum of understanding between VT and NH to develop a common approach to the river that forms their common border.

Hydrology & the Upper Connecticut River

Kathy Fallon Lambert, hydrologist and author of the 1998 report Instream Flow Uses, Values, and Policies in the Upper Connecticut River Watershed, followed with an instructional review of instream flow, including the basic hydrologic cycle and characterization of flow by hydrograph, before reviewing the various forms of dam management. She noted that there are benefits and consequences to flow management.

The river's flow depends both upon precipitation and upon how water is held back, removed, or released, either directly at dams, through water withdrawals, or as a result of forest clearing or land paving activity in the watershed. The Connecticut River and its watershed are heavily regulated: 45 dams impound over 50% of the river's mainstem, and more than 1,000 dams affect flow of tributaries in its basin.

Observing that a number of the mainstem dams are capable of increasing flows ten fold over a one day period, she noted that these facilities demonstrate a marked ability to manage flow on the river. More information is needed on the extent and influence of minor or abandoned dams.

There are three major forms of dam operation: flood control, hydropower run-of-river and hydropower store-and-release. The nature of the operation has a dramatic influence on the changes in stream flow. Flood control dams decrease the magnitude of high flows, increase the duration of high flow events and can both increase and decrease the rate of change in stream flow by shutting off flow prior to a flood or flushing flow to remove sediments behind a dam. In reviewing flow on the Black River before and after construction of flood control facilities, she asked whether such dams should be built to control low frequency floods or higher flow events. She also noted the role of the Connecticut Lakes, particularly Lake Francis, in strongly augmenting flow on the river, especially during the summer months.

Hydropower run-of-river (ROR) projects can have a subtle influence on daily flow. If operated consistent with ROR standards, stream flow should not change measurably from an unregulated river. However, Ms. Lambert noted that some ROR operations within the Connecticut River watershed have shown fluctuations that deviate substantially from ROR standards.

Store-and-release hydropower projects can increase both the severity and occurrence of low flow events. The degree of flashiness or rapid increases and decreases in stream flow is generally greater with store-and-release projects. The magnitude of extreme high flows and increase or decrease depending on project capacity and operation.

In addition to dams, urbanization and water withdrawals also affect river flows. Less is known about the extent and impact of water withdrawals in the watershed. There are 80 known surface water withdrawals in the watershed, and likely more that are unreported. Ms. Lambert observed that there may be less water available to the river's base flow in summer because of reduced infiltration.

Research Biology & River Flows

Mark Bain, whose research team from Cornell University had studied a southern riverine community, described the effects of constantly changing flows on fish species. He noted that among smallmouth bass, individuals that are big and mobile are not really affected by regulation of flows. In contrast, those restricted to shoreline areas where habitat changes according to the river's flow regime are affected by flow regulation. For example, young smallmouth bass are affected while adults are not, and shallow, slow-moving fish populations decline sharply below a flow-regulating dam. He and his students identified fish species which are "fluvial specialists," and found that at greater distances from a flow-regulating dam, the aquatic community demonstrated greater diversity and larger fish populations. He described the results of flow restoration on the Tallapoosa River in Alabama, where the net effect of enhancing flows was the return of a more natural fish fauna.

Dr. Bain agreed with Lambert's observation that higher flows are the channel forming flows, and that the shape of a river's channel is greatly influenced by bankfull flows. He compared the runoff and sediment movement from various types of land cover and suggested that sediment transport should be considered in flow policy.

type of land cover

sediment eroded per acre

% of precipitation leaving the land as runoff


0 sediment



.04 tons/acre



73.2 tons/acre


Noting the increasing attention to invertebrates and habitat in the regulation of rivers, Dr. Bain described the effects of a "created flood" on the Colorado River. Discussion focused on the emerging interest nationwide in simulating channel-forming flows on managed rivers that may no longer otherwise experience these conditions.

Benefits of Flow Management

Mark Wamser of Gomez & Sullivan Engineers described the benefits of flow management, noting that hydro power is being marketed as "green power" elsewhere in the country, although there will be criteria to be met as to whether hydro can legitimately be considered "green." If hydro power was not available to meet energy demands, however, alternative sources such as coal or oil would be needed. These alternative sources result in other environmental impacts, such as air pollution.

Mr. Wamser suggested that deregulation in the hydroelectric industry will result in more "peaking" operations. By storing water to generate at a later time, a hydroelectric project is able to instantaneously supply power at times of high demand. Projects that operate with this as their primary objective are called "peaking power" projects.

Reservoirs both reduce downstream flooding and supplement seasonal low flow conditions. Many hydroelectric facilities in the Upper Connecticut River have large seasonal storage reservoirs whose water levels are drawn down in the winter and refilled after the spring freshet. Although reservoir draw downs are undertaken to benefit hydroelectric generation, they also serve to reduce downstream flooding along the Connecticut River. In times of low flow, water is commonly drawn from the large seasonal storage reservoirs like Lake Francis, to supplement natural low flow conditions, aiding in waste assimilation by increasing mainstem flows to the benefit of dischargers and consumptive users.

The creation of reservoirs for hydro power generation has resulted in various recreation opportunities including canoeing, boating, swimming, flat-water fishing, and picnicking. White water boating opportunities may be created below hydroelectric facilities with peaking operations. Mr. Wamser pointed out that the relicensing of the Fifteen Mile Falls project has resulted in the significant benefit of easements for conservation purposes on over 11,000 acres of land surrounding the Connecticut River. In addition, a fund has been established for river restoration projects, enhancement of wetlands, and restoration of natural buffers.

He balanced his discussion of the many benefits associated with hydro power projects and the seasonal use of storage with a note on impacts, which include: loss of riverine habitat and spawning grounds; impact on water quality (dissolved oxygen and temperature); impact of peaking operations on aquatic biota (fish stranding, shifts in habitat); fluctuating water levels at reservoirs that impact wetlands, wildlife, fisheries, aesthetics; fish passage and access to spawning grounds, and fish entrainment and mortality at turbines.

Federal & State Policies that Affect Flows on the Upper Connecticut River

Ralph Abele of EPA recalled changes in the public's view of water quality evaluation through the time period culminating in adoption of the Clean Water Act, which now recognizes that the physical, chemical and biological integrity of a river system involves both quality and quantity.

Over the last decade EPA has encouraged states to look beyond chemical specific criteria in the development and implementation of water quality standards. In 1991 EPA's Assistant Administrator for Water clarified this in a letter to the Secretary of the Federal Energy Regulatory Commission: "protection of water quality involves far more than just addressing water chemistry. Rather protection of water quality includes protection of multiple elements which together make up aquatic systems including the aquatic life, wildlife, wetlands, and other aquatic vegetation, and hydrology required to maintain the aquatic system."

In 1996 EPA New England wrote to each of the six New England states and identified instream flow as a high priority water quality issue. EPA believes that we all have a responsibility to tackle the flow problem; a responsibility to work better together, between the states, between the state and federal governments, and between the public and private sector, to better manage flows. EPA New England and the New England Interstate Water Pollution Control Commission met with the six states and identified several mechanisms by which EPA would work closely with them: water quality standards, Section 401 water quality certification, and assistance with development of state-specific flow rules.

State Water Quality Standards: EPA-approved state standards are critical to protecting the "goal uses" of the Clean Water Act which include "the protection and propagation of fish, shellfish and wildlife." Water quality standards serve the dual function of establishing goals for a water body and providing the basis for regulatory controls. They are applicable to all waters, including rivers, lakes, streams, natural ponds, wetlands and tidal waters, which lie within a state/tribal boundary and which meet the definition of "waters of the United States."

Water quality standards for each water body include two elements: the designated uses of that water body, and specific criteria designed to protect those uses. While attention is often focused on the criteria, the designated uses are of equal importance--and in many circumstances provide authority for states to regulate water withdrawals. EPA regulations also require that state water quality standards include an anti-degradation policy and implementation procedures that ensure the protection of existing beneficial uses and high quality waters. EPA is an active player in the states' process for determining water quality standards. EPA has worked with, and will continue to work with, states during the standards revision process to incorporate language that recognizes the importance of instream flows to the protection of water quality and physical components of aquatic habitat.

New Hampshire Water Quality Standards: NHDES is currently working on a water quality standards revision that includes language that requires surface water quantity at sufficient quantity to protect existing and designated uses. Recognition of flow quantity is also in the state's proposed anti degradation implementation procedures.

Vermont Water Quality Standards: The Vermont Water Quality Standards were amended by the Water Resources Board on June 10, 1999 with an effective date of July 2, 2000. One of the major proposed amendments is the adoption of hydrology policy and criteria providing guidance regarding the extent to which water levels and stream flow can be manipulated.

Section 401 Certificate: Mr. Abele described the Section 401 process under the Clean Water Act, which provides a mechanism for EPA to help states resolve interstate issues, and allows the states an opportunity to require consideration of flow to allow a waterway to maintain its designated uses. A recent legal ruling in the State of Washington determined that states can impose minimum instream flow requirements on FERC-regulated projects. In 1995 the United States Supreme Court ruled that a state may deny certification pursuant to Section 401 to a project which will interfere with a designated use set forth in the state's water quality standards--even if specific criteria will not be violated. (PUD No. 1 of Jefferson County v. Washington Department of Ecology, 114 S.Ct. 1900 (1994).

Mr. Abele noted that both VT and NH are examining flow issues more closely, VT through the experience of revising its water quality standards, and NH through the drafting process for its instream flow rules. He raised the question of potential groundwater depletion, and its effects on river flows, suggesting that this is the time to anticipate the issue.



Moderator Alec Giffen offered a challenge to the conferees: how do we retain the essential benefits of flow regulation while recognizing that we should pay more attention to certain aspects of environmental quality to more closely mimic natural flow? Should 1-2 year floods be allowed to pass downstream for channel form maintenance? He recognized that there are tradeoffs among environmental benefits as well. He recommended improving the information base for flow managers and regulating authorities, as a first step.

Research & Information Needs

Jim MacCartney of the NH Rivers Program at DES facilitated a working session in which participants agreed on the goal of improving the body of information that exists to inform flow-related decisions. These ideas may help shape the regulatory climate or decisions regarding management of specific facilities.


1. Monitoring is a first priority, and includes follow-up sampling and biomonitoring under varied flow conditions.

2. GIS mapping should be expanded, and attached to flow models such as has been done in New York State, with the goal of providing a build-out analysis to show the influence of urbanization and development on hydrology.

3. Undertake ongoing data collection and analysis of daily flux, ramp rates, relation of hydrology to natural communities, temperature, water quality, and similar parameters. It is important to recognize the value of long term data, preserve historic USGS stream flow gages, and expand the data collection system.

4. Long term biological monitoring of fish and wildlife populations and aquatic communities is needed.

5. Habitat suitability indices should be refined, and include non-fin fish species (shellfish, macro invertebrates, plants).

6. Additional ice study is needed to examine channel scour and ice effects on river morphology, sediment transport, and the biotic community.

7. Identify flows that will lead to maintaining or improving channel shape.

8. A sediment accumulation study is needed to identify the degree and composition of sediment impounded behind all the dams in the watershed.

9. Accuracy of flow gages should be determined by comparing current and historical records and weighing effects of changes in background conditions (log drives, forest type, dams, regulation, climate) upon gage record quality.

10. A long-term analysis of flood plains and the aquatic terrestrial zone should be undertaken to assess the river's response to changing conditions within the flood plain.


11. Water use management plans should include groundwater, stream setbacks, hydro geologic analysis, safe yield, and travel time.

12. NH and VT water quality standards should be compared and refined to improve compatibility.

13. A legal analysis is needed of historic water use authorizations by legislatures, their current status, and their legal soundness.

14. The adequacy of Instream Flow Incremental Methodology (IFIM) as a planning tool should be evaluated.

15. Proactive flow needs assessment should be undertaken before prompted by proposed projects.

Opportunities to Improve Policy

In a work session facilitated by David Deen of the Connecticut River Watershed Council, there was a shared recognition that the diverse uses of the Connecticut River watershed's flows would benefit from a common policy framework forged between the two states, and that flow considerations deserve higher priority. The discussion addressed the questions of lead responsibility and content for such a policy.

Participants noted the array of jurisdictions, agencies, commissions, and interests, and asked how they could efficiently improve coordination. The facilitator acknowledged the evidence of different agency cultures and the political implications of much of the discussion, but credited participants with avoiding "turf" issues. He suggested that the CRJC should remain a key player in the discussion, although not the sole force. The group participants recommended CRJC, the two water resource boards, the Army Corps, PG&E Gen, and the two state water agencies to set up a framework for a policy sufficiently sketched out to allow drafting of specific standards. NEIWPCC was also suggested as an appropriate partner.

Lynne Hamjian (EPA) advised learning from the states' recent water quality standards processes, including the complexities and the politics, because some of the same players will be involved in any effort to develop coordinated policy for the Connecticut River. It was agreed that flow policy should be forward looking, and seated in a projection of potential demands and conditions on the river in the future. Policy makers should identify the problems with the existing situation and explore opportunities that could be provided by a flow policy for the Connecticut River.


1. Determine and articulate a clear statement of need for new flow policies for the Connecticut River.

Actions: Recognize that a framework for flow policy already exists in the provisions of the Clean Water Act, and in the findings of the report, Instream Flow Uses, Values & Policies for the Upper Connecticut River Watershed. Make a concerted effort to gather, analyze, and disseminate information on the values and functions of all stages of flow in the river.

Implementation: One agency or organization should be given the charge to gather information from all stakeholder groups and focus the effort to synthesize the statement of need.

2. New Hampshire and Vermont should develop an integrated flow policy for the Connecticut River watershed that addresses maximum as well as minimum flows, and begins with a cooperative approach to incorporating flow factors in water quality standards. Both states should then develop an implementation plan to achieve the agreed upon flow levels for the river.

Actions: Establish a pilot project for interstate flow standard development. The flow policy should become a single written document so users can understand policy. The policy should be validated through a public process, and incorporated in both states' rules.

Implementation: The full range of users, state and federal regulators, and citizens should be involved with the work to develop an integrated flow policy, facilitated by a lead organization or entity.

3. Incorporate environmental impacts when evaluating whether to recommit the public trust resource to present uses. Any decisions about changes in flow policy should consider present and potential uses of the resource.

4. Improve communications between all parties using the river resource, and improve coordination between dam owners/operators and regulators throughout the watershed.

5. Create a process for regulators in both states and the US Army Corps of Engineers to develop a coordinated approach to increasing the downstream flows at US Army Corps flood control facilities.

6. Appropriate flow levels on the Connecticut River should be a higher priority in decision-making by regulators.

Enhancing Coordination Between New Hampshire & Vermont

Nancy Girard, of the Conservation Law Foundation, guided a discussion which concluded that it will take a few years and an extensive effort to completely articulate a flow policy for the Connecticut River. A statement of need could be prepared, using the recently completed report on Instream Flow Uses, Values, and Policies in the Upper Connecticut River Watershed. Specific actions to be taken should be refined in an analysis of problems and opportunities, and tested against experience. It is important to assess what can realistically be achieved in the political sense. Agreement on the designated uses should be the precursor for developing the policy. It was agreed that such an articulation of need is doable, with further steps arising from this.

Participants differentiated between a formal versus informal process of improving policy, which is sensitive to the political process and involves work with colleagues in the other state. This discussion group favored coordination among professionals in both states as much as possible, without mandates from "on high." Given a choice between state to state communication toward flow policy improvement, versus improvements derived from federal oversight, most participants favored a state -initiated process.

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