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Flow + Ecology​ Policy Implementation Case Studies Bibliography


Water policy implementation based on ELOHA enables sound science-based environmental flow management throughout an entire state, province, or country -- not just for individual rivers.
ELOHA’s “social process” is typically a policy-making effort driven by a new law, regulatory rulemaking, or policy guidance. Such a process is almost always led by a governmental authority and often closely involves stakeholders. The determination of “acceptable ecological conditions”, or ecological condition goals, for river and stream segments has similarities to many state water quality programs that classify water bodies according to water quality attainment goals. This goal classification is distinct from the scientific classification of natural river types.
Condition goals, also known as desired future condition, underlie all environmental standards. Within any large region, people value different rivers for different purposes. They may strive to keep certain rivers nearly pristine, while accepting that other, more developed rivers simply maintain a basic level of ecological function. Stakeholder negotiations that focus on applying different standards to rivers with different ecological condition goals generally lead to successful implementation.
The environmental flow standard, or criterion, is the degree of allowable flow alteration associated with each condition goal, according to the flow-ecology relationships. It is the limit on hydrologic alteration designed to achieve a set of management goals.  An ecological risk-based framework associates ecological goals with allowable flow alteration, and accounts for scientific uncertainty by associating appropriate policy actions with different levels of ecological risk. Decision support systems greatly facilitate the integration of environmental flow standards into state water allocation programs and regional water resource planning.
Although ELOHA provides a useful framework to guide the development of environmental flow criteria, there is no one-size-fits-all approach. Regardless of the rigor of the scientific analyses, expert judgment calls are required to adapt the process and to interpret results. Facilitated expert workshops and advisory panels improve the outcomes and their credibility to the public. The level of sophistication needed depends ultimately on what policy makers want and stakeholders will accept. Early outreach to stakeholders, the definition of shared guiding principles, the formation of advisory committees, attention to political and economic drivers, and process transparency are all likely to pay dividends in environmental flows implementation.
Many countries have recently passed progressive laws requiring that natural flow variability and its dependent ecosystem functions be maintained.  But how can such a lofty goal be accomplished at the scale of an entire country, when environmental flows for a single river can require years to determine?  That question is exactly what ELOHA was designed to answer.
The ELOHA flow chart captures policy implementation as the "social process" along the bottom row.  In this process, standards for environmental flows are determined through administrative, legislative, or legal processes.  The process incorporates stakeholders' values for the range of ecosystem services that are provided by rivers and streams.  Flow-ecology relationships link the social process to the scientific process of ELOHA by relating ecological condition, which is the policy goal, to hydrologic alteration which is the management tool for achieving the goal.  Thus, these relationships inform the establishment of environmental flow standards.
Acceptable Ecological Condition Goals
The social process (see flow chart) begins by determining acceptable ecological condition goals for every river, based on societal values and management needs.  Acreman and Dunbar (2004) distinguish objective-based from scenario-based approaches for setting such goals.

In some places, every river is assigned the same ecological condition goal.  For example, in Michigan, USA, a single ecological objective -- maintaining healthy fish assemblages -- is used statewide.  There, stakeholders decided that no river should be allowed to degrade more than a set percentage from its current condition, measured in terms of fish community assemblage.  Similarly, the European Union Water Framework Directive requires member states to achieve "Good Ecological Status" in all surface and ground waters that are not heavily modified.  The United Kingdom is using an ELOHA-like approach to translate this subjective term into sustainable water use measures to integrate into overall river basin management.

In other places, rivers are assigned ecological goal classes so that every river need not achieve the same goal.  In the United States, Maine and Connecticut have established the following goal classes, and associated specific degrees of allowable flow alteration to each goal: 
Class AA - Outstanding natural resource for preservation, habitat is free-flowing and natural
Class A - Habitat for fish and other aquatic life is natural
Class B - Habitat for fish and other aquatic life is unimpaired
Class C - Habitat is suitable for fish and other aquatic life
Class GPA (lakes) – Habitat for fish and other aquatic life is natural
Class 1 - Natural
Class 2 - Near Natural
Class 3 - Ecologically Sufficient
Class 4 - Ecological Non-Attainment Waters
The State of Maine embarked on establishing flow and water level regulation, following several years of drought in the 1990s and early 2000s, leading to passage of legislation in 2002 which defined (1) the state’s jurisdictional interests, (2) water use reporting requirements, and (3) authorized the establishment of standards for flow (for rivers and streams) and water level (for lakes, ponds, and impoundments) which became a rule instituting both numerical criteria and procedures for their implementation.
The legislation linked flow and water level regulation to water quality goals in Maine’s water classification law that contains specific biological goals for all classes of waters.  Language in in Section 470-H of the statute requires that rules are “protective of aquatic life and other uses” … “based on the natural variation of flows and water levels” … “allowing variances if use will still be protective of water quality within that classification”.  Read more about Maine’s ecologically-based flow policy in ELOHA case studies.

In 1971, the Connecticut legislature passed a law requiring the protection of environmental flows for the “stocked streams” of Connecticut—that is, those rivers and streams stocked with fish by the Division of Wildlife. In 2005, at the request of environmental advocates and with the concurrence of water users, the legislature updated this statute to require the Department of Environmental Protection (DEP) to develop environmental flow regulations for all rivers and streams in the state while also providing for the other uses of water.

In South Africa, draft Regulations for the Establishment of the Water Resource Classification System set a process for classifying the country's water bodies into ecological goal classes ranging from A to F, representing different levels of deviation from pre-development biophysical conditions. The draft regulation also outlines how to determine the Ecological Water Requirements needed to achieve these ecological goals.  Hirji and Davis (2009b, pages 31-40)  provide an overview and assessment of South Africa's National Water Policy and legislation.

Finally, stakeholders in some places value different rivers within a single river type differently, and therefore assign different levels of ecological risk and corresponding allowable degrees of flow alteration to each river.  In Florida, USA, and in Australia, government leads this effort.  In Texas, USA, local stakeholders play a prominent role.


Environmental Flow Standards

Flow-ecology relationships associate ecological condition goals with enforceable environmental flow standards.  In this example, modified from Michigan Groundwater Conservation Advisory Council (2007),stakeholders set an ecological condition goal of 97 percent, allowing 3 percent degradation from the current ecological condition, quantified in terms of a fish population metric.  Scientists determined the shape of the curve that relates the fish metric to an enforceable flow metric, in this case median August streamflow.  This ecological goal translates into an environmental flow standard of 0.26, meaning no more than 26 percent of median August flow may be removed.  The hydrologic goals differ according to river type because each of the State's 11 river types has a different flow-ecology relationship.


Implementing Environmental Flow Policies

Of course ELOHA can't set flow standards in a vacuum.  Government uptake and implementation of flow standards depends on effective coordination of legislators, regulators, stakeholders, and scientists to establish conducive enabling conditions.  In January 2010, a team of ELOHA practitioners from Mexico and the US prepared a summary of implementation phases needed to integrate ELOHA into the broader social and political contexts in which water is managed.

Before launching environmental flow policy reforms, it is important to understand the policy context, including all of the relevant opportunities and constraints.  For example, The Nature Conservancy recently commissioned a detailed evaluation of Oregon (USA) water laws and policies related to instream flow management.  As of November 2012, eight US states and three Native American tribes have adopted explicit narrative water quality criteria for protection of instream flows into their state water quality standards under the Clean Water Act.  
Regardless of whether environmental flow targets are implemented as enforceable standards within a regulatory context or as long-term goals within a planning context, there are numerous means for achieving them.  The following list is not inclusive:
Environmental flow restoration
·   Dam re-operation
·   Conjunctive ground-water / surface-water management
·   Drought management planning
·   Demand management (conservation)
·   Water transactions (exchangeable water rights)
2007 (Brisbane) and 2009 (Port Elizabeth) workshop proceedings
·   Diversion point relocation
Environmental flow maintenance
·   Dam siting and operation
·   Permit system for withdrawals
See LeQuesne et al (2007) and LeQuesne (2009)
·   River basin management
Because the hydrologic foundation accounts for the cumulative effects of all water uses, it can be used to assess the practical limitations to, and opportunities for, implementing environmental flow targets at any analysis point in the project area, or for every point simultaneously.  It can be used, for example, to prioritize restoration projects, optimize water supply efficiency, or account for cumulative upstream and downstream demands in permitting decisions.  For basins in which water is already over-allocated, it can help target flow restoration options.  While economics is frequently used as a framework for decision making (Acreman 2001), flow-ecology relationships and the hydrologic foundation can link economic measurements to ecological condition.  Thus, the hydrologic foundation anchors decisions about future water allocation and river management to a comprehensive understanding of the availability, location, and timing of the flows needed to maintain or restore the overall health of a region's river ecosystems.
Monitoring Implementation
The development and implementation of regional environmental flow targets is an ongoing, iterative process in which data collection, monitoring, evaluation, and evolving social values continually refine the targets and the flow-ecology relationships upon which they are based. Environmental flow monitoring also helps discern the relative roles of compliance, infrastructure, flow restoration, and other ecological improvements such as channel restoration, pollution abatement, and fishery management in successfully achieving agreed-upon environmental outcomes.
The monitoring system should be able to answer these questions, at a minimum:
·   Are the target environmental flows being delivered?
·   Are the ecological responses as predicted?
·   What are the social and economic outcomes?
Enabling Conditions
An informed public, political commitment, and strong institutional framework are essential for implementing environmental flow policies based on ELOHA.  Acreman et al (2005) articulated a ten-step approach for establishing the laws, institutions, capacity, training, and data centers needed to implement an environmental flow program in Tanzania and other developing countries.  The Southern Instream Flow Network provides parallel recommendations for the southeastern United States and other developed countries.
The World Bank (Hirji and Davis, 2009a) examines enabling conditions for establishing and, more importantly, implementing national environmental flow policies based on the experiences of the European Union, Australia, South Africa, Tanzania, and Florida (USA).  LeQuesne et al (2010) identify three obstacles to flow policy implementation and offer nine guidelines for overcoming those obstacles, illustrated by diverse experiences from around the world.
Policy Language
At least 19 principles guide best practice in environmental flow policies, which should be enshrined in policy language and practice.  To paraphrase a few:
·   Maintain a seasonally variable flow regime -- not just minimum flows
·   Protect entire, functioning ecosystem -- not just single species
·   Set limits on flow alteration
·   Provide for both protection and restoration of flows
·   Involve all stakeholders who depend on healthy freshwater ecosystems
·   Integrate environmental flows into all aspects of regional water management via an accurate water accounting system, such as ELOHA's hydrologic foundation.
·   Require monitoring and allow for adaptive management.
North Carolina's Senate Bill 907 was introduced to the state legislature in March 2009.  If passed, S907 would establish a model water rights system that protects environmental flows.  The water management agency would be required to use an "approved" hydrologic model as a decision support system for permitting water allocations.  Conservation and efficiency would become priority water management strategies.
Florida's Minimum Flows and Levels statute has been revised over the years as the science has evolved, and now allows for seasonal flow variations. The statute sets out a process for local water districts to establish and implement environmental flows.  Some water bodies are excluded if their recovery to historical hydrologic conditions is not economically or technically feasible, and would cause adverse environmental or hydrologic impacts to other water bodies. 
Spain introduced environmental flows to its legal framework through its 2007 Water Planning Decree, in compliance with the European Union Water Framework Directive.  The 2008 Basin Water Resource Planning Standard details the required environmental flow methods for its implementation.
The following existing or proposed water policies also address environmental flows:
  • Canada British Columbia Water Sustainability Act, passed in April 2014, requires that allocations of surface and groundwater consider environmental flow needs.
  • Colombia Resolution 0865 explaining how to calculate the water scarcity index, including the ecological flows index, 2004 (en español)
  • Ecuador Water Resources Law , 2009 (en español)
  • Japan River Law, commentary, and analysis, 1999
  • New Zealand proposed ecological flow and water level standard, 2008


 Key Resources