Our work in the State of Kerala, India in the matter of river restoration is primarily to detect and limit physical encroachment, bring back biological productivity, identify sources of pollution and combat them at the source including household level sources, wastewater management, and improve flow character. We are trying to create awareness among people about the peril of river degradation and how it will retard the development process. We do not consider the uninstallation of the dams and barrages which are essential infrastructures for the development of our State.
We must accept the co-evolutionary character and hybridity of the river systems and intervene to restore river functions as far as possible. Since its adoption into French law in , the ecological continuity of rivers has been one of the most significant policy developments affecting rivers in the country.
To put the concept into practice, the removal or adjustment of hydraulic works that obstruct river continuity is privileged. In inventory done in listed some 95 hydraulic works in Metropolitan France.
A vast majority of these are small-scale works including weirs, milldams and ford—crossings. Applying the policy of ecological continuity, however, has generated much conflict opposition by mill-owners to the destruction of their property; unwillingness of residents to alter the waterscapes that they have become familiar with and scientific controversy over the scientific validity of the concept itself to the effectiveness of removing hydraulic structures.
This produces three types of problem : struggles between direct uses e. The ecological continuity of rivers — and the way it is implemented — in France produces a new type of conflict associated with a new category of the ecological moment; namely non-uses, or non-use values of the river, such as the provision of ecological services, habitat maintenance, etc.
Prior to the current cycle, non-use values did not exist as such. This new category of conflict — between uses of the river and non-use values — revolves around the question of the future of existing hydraulic works such as dams, mills, fords, bridge pillars, weirs… As mentionned in my PhD, the environmental ethics anthropocentric, eco-centrism and bio-centrism with different variations could be use as a type of explanation of the 'conflictuality' because they reflect various ways of knowing, grasping and representing rivers.
There are multiple perspectives and multiple expectations linked to different ways of accounting for and valuing river amenities. This multiplicity gives rise to difficulties, as shown by the conflict between those who value the cultural heritage of millponds and those who value the natural heritage of free-flowing rivers. Furthermore, I have an intuition that knowledge about rivers and values are linked.
It will be interesting to study this relationship in actors of river management. I noticed this link between environmental ethics and understanding of aquatic environments. Of course everything is up for discussion : this is just some observations during my Phd. The issue of ecological restoration through the removal of dams is often more associated with large dams and the 'salmon issue', e.
The heated debate, in France, about small weirs removal their number is estimated at 80, is quite fascinating. Christian mentioned it in his post. Different ecosystems have been created by these often very old impoundments but the idea of nature as a free-flowing river, without manmade obstacles, militates for their removal. These aquatic environments and also the historical heritage dimension of these infrastructures are often valued by local populations.
Scientific uncertainties about the exact impact of most of these small weirs contribute to fulling opposition. I would be interested to know if a similar debate is observed in other countries. In most places restoration takes place balancing environmental objectives, economics, and livelihoods.
Examples at hand include an ongoing interstate case in the US Florida Vs. Georgia , and the detailed procedures and limits of Spanish legislation. However, in a recent case in Argentina Atuel River the Supreme Court went ahead with an order for restoration without taking into account impacts on irrigation systems to be foregone, employment, income, and social security.
The judicial process was not open to render evidence. Cost and benefits for people and economy were not assessed, and a superior overarching environmental priority was stated. People and the economy were of no consideration, and the impacts of climate change on the disappearance of glaciers supplying and regulating water runoffs were not considered.
Previous adjudications protecting existing irrigation systems and water rights were ignored. This extreme approach to restoration is ideological, rather than balanced, and is bound to elicit political and social resistance in the future. Irrigation is the basis of economic activity and employment in the area where water rights are to be foregone without compensation. It was completed in The Canal was never completed: President Nixon ordered it stopped under pressure from environmentalists in But the dam remained as it is.
It created the Rodman or Oklawaha Reservoir, covering an area of 5, ha, and drowning a large flood plain forest while also engulfing 20 freshwater springs. Since that time, there have been numerous attempts to remove the dam, with multiple court cases, petitions, etc. In Northern Florida you can easily stir up heated debates by just mentioning this dam.
The defenders of the dam like the recreational opportunities it has created: boating and fishing. They argue destroying the dam would displace many species that now count the reservoir as home and would affect local businesses who provide services to tourists and fishers. The reservoir is considered one of the top bass fishing lakes in the USA. Ecologists and environmentalists do not buy these claims and want to restore the native fish populations and the natural forest.
They argue that there would still be substantial opportunities for fishing — striped bass for example. The water is stained brown, sea lettuce clogs the waterways below the dam, and crushed plant matter floats to the surface and smells. The two sides are at an impasse. Compromise solutions involving less destruction of infrastructure have been proposed, but the political will and funding are not there.
The potential impact of removing the dam is uncertain — it seems unlikely the pre-dam ecology will re-emerge in pristine form. But the current man-made ecosystem also leaves much to be desired. First introduced by Socrates, the father of Greek philosophy and reported by Plato, a dialectical process means a creative confrontation between two contradictory concepts that may have different logical explanations.
In dialectic, a unified approach between contradictory issues may lead to more resilient and even sustainable solutions. This is not a multi-disciplinary view but rather a holistic approach in which benefits and harm to nature induce also benefits and negative effects on man and society.
Man and nature although being interdependent and complementary are traditionally analyzed and studied separately. In the University, social and natural sciences are different disciplines and from the anthropogenic view, man is considered separately from the natural world mostly as an opponent rather than as a complement of nature.
In our discussion, benefits result from training rivers and also losses occur in doing so. This apparent dialectical contradiction between benefits and losses from the same action has of course a simple logical explanation: benefits derive from facilitating river transportation or flood protection and negative impacts are due to possible loss of fisheries and ecosystem degradation.
We could multiply similar dialectical examples as human interventions to nature, like building dams for energy production or over-drafting groundwater for agriculture may damage transitional river ecosystems and deplete aquifers. To move from philosophy to applications, the holistic dialectical approach means not just a compromise solution between different technical alternatives, but a resilient solution based on natural laws.
To support this statement I will briefly cite two examples from my personal experience: the first relates to the fact that in the northern hemisphere, when tidal forces are negligible, like in the Mediterranean, earth rotation induces Coriolis forces that turn river beds near the shore dextrally. We have respected this bed morphology in the Giofyros River delta, during the flood protection works of Heraklion, the capital city of Creta. I find that the approach to Eco Vs. Human should be tailored to specific cases.
The answer cannot be the same in arid and humid areas. When irrigation is developed in arid areas, over years and centuries, any decision should take into account the economic basis and losses of irrigated areas, population affected, investments to be foregone and, of course, the costs economic, social, environmental of compromising the sustainability of man made oasis.
If they go away cities, infrastructure, and livelihoods including ability to pay the taxes that sustain public services and utilities go with them. Planning ex post is much more demanding than planning ex ante. One size fits all does not easily apply here. The magnitude of social damage that may take place is staggering. High planning and assessing capabilities are called for. Simplistic legal and judicial decisions are not up to the task.
Congratulations for this important discussion. I was the Director of Chile for twelve years. As you know the Chilean economy is heavily dependent on water for irrigation, mining, industry, hydro, and urban water supplies. This monitoring should be required of all projects and included in the centralized database. This ensures compliance with permits and with stated intents and requires that monitoring be part of project planning and designed in light of project goals.
Effectiveness monitoring involves an in-depth research evaluation of ecological and physical performance to determine whether a particular type of restoration or method of implementation provides the desired environmental benefits. Because effectiveness monitoring is time-consuming and expensive, it is unrealistic to make this a routine expectation. However, it is necessary when comparing the effectiveness of different restoration approaches, when evaluating unproven restoration practices, or when the ecological risks of a project are considered high.
The national tracking of restoration projects, including implementation and effectiveness-monitoring information, will ensure that projects are chosen wisely and that money is spent carefully. The EPA is a good candidate because of its role in overseeing compliance with the CWA and involvement in ecological monitoring. The U. Geological Survey is also a good candidate because of its involvement in water science and stream-flow monitoring.
Undertake a national study to evaluate the effectiveness of restoration projects. Because restoration effectiveness has not received adequate attention, it is not always clear which restoration methods are most appropriate or most likely to lead to ecological improvements.
Agency practitioners often rely on best professional judgment that their projects are meeting intended ecological goals, rather than undertaking scientific measurement and evaluation. Only a small fraction of projects are currently being monitored to determine their relative success, so little is known about the environmental benefits.
Something must be done to ensure that projects are doing what they set out to do and that money is well spent. Although monitoring of project effectiveness in meeting ecological goals is always desirable, not every project requires sophisticated and costly effectiveness monitoring. In fact, many people worry that such an expectation would diminish the number of restoration projects on the ground by siphoning off available resources. One way to balance the need for evaluation and accountability with limited resources is to conduct detailed monitoring of a sample of projects.
The information gained would provide an efficient means of understanding project effectiveness and help restorers learn from the experience of others. Such a program could involve detailed monitoring of a sample of all projects within each of the major categories of river and stream restoration, perhaps beginning with the most interventionist restoration practices such as channel reconfiguration or the most costly forms of restoration such as floodplain reconnection.
In , Congress included language in a Department of the Interior appropriations bill that directs the National Research Council NRC to examine federal and nonfederal water resources programs and provide recommendations for a national research program that would maximize the efficiency and effectiveness of existing programs.
The NRC has completed several reports that evaluate water research programs and is considering a study on river restoration. We recommend that such a study panel be funded immediately and directed to recommend the design, scope, and costs of a new research program. The program should explicitly evaluate which restoration methods are most effective at achieving the desired goals and delineate which project types require only modest compliance monitoring and which need detailed monitoring.
Because the data are currently insufficient to enable an NRC study committee to reach firm conclusions through synthesis of existing data and expert analysis, the panelists should be directed to identify needed further research. Furthermore, the panel should identify the appropriate agency to oversee this research program in order to ensure that peer review of all research is conducted and that restoration effectiveness data are collected by an entity that is independent from those conducting or funding restoration.
It is standard practice to conduct double-blind studies when human health is concerned. It is no less important when the future of clean water and freshwater resources is at risk. Use existing funding for river restoration more efficiently and supplement funding. Although there are many areas in which Congress and federal agencies could make improvements in the policy and practice of river restoration, it is first necessary to ensure that existing funding is wisely allocated so that projects are successful.
That means developing a mechanism to authorize and fund restoration projects in a much more coordinated fashion than the balkanized system that supports them today. There are more than 40 federal programs that fund stream and river restoration projects.
Although large-scale high-profile projects such as those in the Everglades receive a great deal of attention, most projects in the United States are small in spatial extent.
The cumulative costs and benefits of the many small restoration projects can be very high, which argues for better coordination.
Like WRDA, WRRA would support projects of various shapes and sizes, all for the purpose of making federal investments in natural capital and infrastructure. Money would still flow through individual agencies, but prioritization and coordination would be achieved through an administrative body with representation from all agencies that fund river restoration activities. That body would ensure that restoration funds are spent efficiently as well as address unmet needs. These projects would yield enormous benefits in the form of ecosystem services, including flood control, protection of infrastructure, and maintenance of water quality.
They also would have benefits similar to those of more traditional infrastructure projects. They create jobs in member districts, but if they are carefully chosen and designed, they can also save taxpayer money. By including interagency tracking mechanisms and building in compliance monitoring requirements to each project, Congress can ensure the necessary feedback and accountability to make these projects wise investments.
Instead of funds being allocated independently by plus federal programs, WRRA would ensure that project prioritization occurs on watershed scales and is based on criteria that are consistent across the nation.
In addition to the need for better coordination and thus more efficient use of existing funding, current funding falls short of what is needed. The magnitude of the problems and the demands that citizens are making for healthier waters require additional funds for cleaning U.
Aging sewer and stormwater infrastructure combined with increased development of the land make it imperative that a combined approach involving better coordination and an increase in funding be a priority. Additional funding will not only make possible more recovery of damaged river ecosystems, but will enable inter- or intraagency mechanisms for tracking projects and allow more pre- and post-project monitoring of their effectiveness.
New funding will not be easy to come by in the current budget climate and with increased competition for investments in water quality. Many federal programs that involve river restoration are being cut, not increased. The growing need for upgrading stormwater and sewer infrastructure goes hand in hand with river restoration; one cannot replace the other.
Only together will they accomplish the goals of improved water quality, more productive fisheries, and the restoration of other services that rivers provide. River restoration is a necessity, not a luxury. People from all walks of life are demanding cleaner, restored waterways. Replacing the services that healthy streams provide with human-made alternatives is extremely expensive, so river restoration is akin to investments such as highways, municipal works, or electric transmission.
Congress already commits billions of taxpayer dollars in public infrastructure through the transportation bill or WRDA. Click here for information about water quality, including public drinking water source areas, salinity, brochures, fact sheets and best management practices for various land uses and activities to help protect water quality and public health. Rivers and estuaries and their importance including information on monitoring and assessing waterways, protecting, understanding, planning, restoring, and risks and threats.
Click here for information on types of irrigators, licenses and the role of irrigation as an economic enabler for industry.
Information and reports collected from the department's extensive State-wide monitoring network, which are provided free for water management, state development and research purposes. Most waterways in Western Australia are modified to some degree and some have been extensively altered so that they retain few of their natural features or values. Waterway restoration may be necessary to maintain or improve their environmental, social and economic services.
Waterway restoration aims to protect and restore the physical form and ecological processes of a waterway in a way that supports it to progress toward its natural state. The Department of Water supports government agencies, industry, natural resource management groups, communities and individuals with planning, implementing and evaluating waterway management activities, including by preparing waterways management plans and supporting river action plans for priority waterways.
We provide guidance and technical expertise about river restoration and management. This includes addressing hydrological issues, restoring channel alignment and form, erosion and sedimentation, stabilising banks, pool and riffle construction, designing fishways, identifying and protecting foreshore areas and the design of living streams.
We also assist with collating and analysing water monitoring data which is used to design and evaluate waterway restoration projects.
This includes data on water quality, ecological water requirements and trends in the hydrological regime, including water levels. This list contains key links and resources to help with assessing, planning, monitoring and restoring waterways:. Skip to content Skip to navigation. Go to Minister for Water. Home Show Sub Nav. Planning for the future Show Sub Nav. Finding water Finding new water resources, including Royalties for Regions-funded programs and other drilling programs to explore resources across the state.
Water allocation plans Information about allocation plans, which set out how much water can be reliably taken from groundwater and surface water sources for productive purposes while ensuring the sustainability of the resource and protection of the water-dependent environment.
Rural water support Click here to apply for rebates and grants for farmers, pastoralists and rural communities to improve local water supplies and for information about assistance to help farmers access water during dry seasons. In 27 percent of the acid streams, organic acids are the main source of acid ions. These streams are located in Florida and the Mid-Atlantic Coastal Plain and are associated with wetlands or organic soils.
In Florida, healthy largemouth bass populations are found in waters with pH ranging from 4. In contrast, the Mid-Atlantic Coastal Plain has experienced a continuing decline of anadromous species since the s. Some streams whose acidity was formerly caused by organic. The United States has a backlog of almost 50 billion tons of old mining and mineral processing wastes Kleinmann and Hedin, Therefore it is not surprising that more than 12, miles of rivers and streams and , acres of lakes and reservoirs are adversely affected by mining in the United States Kleinmann and Hedin, Acid mine drainage—a fluid generally 20 to times as acidic as acid rain—is responsible for at least a third of this ecological damage Kleinmann and Hedin, In sufficient concentrations, acid mine drainage AMD coats stream bottoms with a rust-colored iron precipitate, adds enough sulfuric acid to acidify the water, and kills aquatic life Kleinmann and Hedin, Formed from the oxidation of iron pyrite, AMD is associated with coal mining in the eastern United States and with metal mining in the West.
In the past 20 years, the number of rivers and streams adversely affected by AMD has reportedly dropped by about a third, primarily due to perpetual chemical neutralization of mine water before discharge an expensive process and by reclamation of abandoned mines Kleinmann and Hedin, Some of the improvement, however, has come from natural amelioration by gradual oxidation of the iron pyrite and some by intentional flooding of deep mines to prevent the pyrite from oxidizing. Still other improvements have been gained by construction of cattail wetlands to purify mine wastewater, usually by bacterial action; more than such wetlands have been constructed in recent years Kleinmann and Hedin, Anionic surfactants are also used to inhibit iron-oxidizing bacteria in mine waste piles.
Another technique to control AMD caused by fractured streambeds that leak into underground mines is to seal the streambeds by injecting them with polyurethane grout beneath the sediment-water interface to minimize pyrite-water contact.
However, there are so many other contributing factors that it is not possible to link these declines directly to acidification. These streams are found mainly in the Mid-Atlantic Highlands, where 60 percent of the acidic stream length is due to acid mine drainage.
Although some relatively low-pH streams contain brook trout, their absence from streams with higher pH may indicate that short-lived acidic episodes can determine the composition of fish communities in some regions. The effects of low pH on aquatic life are difficult to separate from the effects of other pollutants, physical habitat changes, and changes in stocking patterns that may be occurring simultaneously.
Also difficult to sort out are the relative contributions of the various sources of acid anions. It appears, for example, that in some streams, shifts may be occurring in the sources of acidity and the relative proportions of organic and inorganic ions e. Sport fish populations appear to be more threatened by habitat loss and pollution than by overharvesting. However, overfishing is a concern in 7 percent of the nation's streams Flather and Hoekstra, , and Narver n.
Projections made by Flather and Hoekstra indicate that as the U. An increasing human population implies a further reduction in habitat, resulting in fewer fish per angler.
Restricting use of the resource is one way to protect it, but local governments are reluctant to reduce recreational opportunities, and even though state and local governments monitor the population and regulate the catch of important species, there is no way to calculate the illegal harvest. Anecdotal evidence hints at widespread violations of size and creel limits, and a lack of law enforcement Burgess, If this is the case, then further regulation may only intensify the illegal fishing pressure.
Releasing hatchery-raised fish is the approach most often used to maintain fishing in many areas that otherwise would not have a sustainable sport fish population. These releases may in themselves constitute a stress when nonlocally adapted strains of fish are released with no understanding of their potential effect on native populations.
Highly inbred hatchery stocks may be successfully adapted. Rock placement individual b. FWS, ; root wads may also be buried trunk first in reconstructed banks to absorb and dissipate flow energy see Boxes 5. Fish originating in different geographic areas may not be able to tolerate conditions, such as low winter temperature, that native stocks tolerate easily. If the introduced fish survive long enough to interbreed with native stocks, their maladaptive genes may not pose a problem until they face an environmental crisis such as an especially.
Organic matter introduction to increase invertebrate production a. Many of the stresses that affect recreational fisheries will also affect commercial fisheries. Salmon populations are closely monitored, and there are already warnings that the salmon harvest is excessive and needs to be restricted to avoid depleting future stocks Weber, If restrictions are implemented, it is likely that salmon prices will rise, but the incomes of fishers and of people employed in salmon-dependent businesses will decrease.
When a resource such as the salmon fishery has both recreational and commercial value, advocacy groups arise promoting their particular use of the resource.
Although sportsmen and commercial fishermen alike recognize that the fishery is a finite resource, allocating the resource appropriately is difficult, with outcomes often based on legalities rather than biological realities Flather and Hoekstra, Previous sections described the structural and functional characteristics of healthy, undisturbed river-riparian ecosystems and the stresses that have degraded these systems.
Here we define and describe the goals and objectives of fluvial restoration. The goal of restoration is the return of an ecosystem to a close approximation of its condition prior to disturbance Chapter 1.
The essence of a fluvial ecosystem is the dynamic equilibrium of the physical system, which in turn establishes a dynamic equilibrium in the. Therefore, the goal of fluvial restoration should be to restore the river or stream to dynamic equilibrium, not to ''stabilize" a channel or bank. The objectives under this broad goal are as follows:. Restore the natural sediment and water regime. Regime refers to at least two time scales: the daily-to-seasonal variation in water and sediment loads, and the annual-to-decadal patterns of floods and droughts.
In arid areas, some organisms depend on rather infrequent occurring only every few years and unpredictable flooding. Organisms in large floodplain rivers in tropical and temperate zones depend on highly predictable seasonal flooding. Restore a natural channel geometry, if restoration of the water and sediment regime alone does not. This step is necessary only if the plant community does not restore itself upon achievement of objectives 1 and 2.
Restore native aquatic plants and animals, if they do not recolonize on their own. Chapter 1 noted that all restorations are exercises in approximation, and fluvial restorations are no exception, given the economic value of water, water-control structures, and structures that are threatened by floods, erosion, and sedimentation.
It is unlikely that natural sediment and water regimes, and naturally dynamic channels, can be or will be completely restored throughout the largest river systems of the United States. Benke found only 42 rivers in the contiguous United States that are more than miles km long and free flowing.
However, there are substantial segments of the Illinois River, Atchafalaya River, and Upper Mississippi River included in public lands e.
The objectives are to add to the existing river-floodplain segments and to restore or rehabilitate degraded segments see appropriate case histories, Appendix A. In the Illinois and Upper Mississippi rivers, levees are left in place around lands being reclaimed from agriculture or mining for fish and wildlife refuges so that the new refuges are not rapidly degraded by excessive sediment loads carried in by floods.
When sediment loads approach predisturbance levels as a result of improved soil conservation in the drainage basin a process that might take 25—50 years , the levees may be breached. In the meantime, water levels within the refuges approximate a natural cycle in response to seepage through the levees, rainfall, and pumps or. The water regime in the restored Kissimmee River will be constrained at the upstream and downstream ends by the need to control water levels in Lake Kissimmee and Lake Okeechobee, respectively.
However, this control can be achieved by leaving gates at the lakes and relatively short lengths of the river channelized at the upper and lower ends. In between, the natural flood cycle and dynamic equilibrium will be restored see case history, Appendix A.
Previous sections of this chapter have documented the types and extent of alteration and degradation of the nation's river-riparian ecosystems. Of the nation's total mileage of rivers and streams only 2 percent are high quality, free-flowing segments according to an analysis Benke, of the Nationwide Rivers Inventory NRI but see "Inadequate Information Base," below.
According to American Rivers, a conservation organization, approximately 8 percent of the nation's river miles are of sufficient quality to be worthy of special designation and preservation, based on analysis of the NRI and compilation of lists provided by state agencies and conservation groups Echeverria and Fosburgh, Only 58 stream segments in 39 states are in the hydrologic benchmark system set up by the U.
The point is that 92 to 98 percent of the miles of rivers and streams in the United States are currently so altered that they do not fit legislative criteria for national rivers or wild and scenic rivers, or USGS criteria for a benchmark stream. Given the extent and economic value of water resource development in the United States, it is infeasible to restore 2,, 92 percent of 3,, to 3,, miles 98 percent of 3,, to a "close approximation of [the] condition prior to disturbance" see Box 1.
It does seem reasonable to set a target of restoring as many miles of river-riparian ecosystems as have been affected by point source pollution and urban runoff: , miles, or 12 percent of the total 3.
EPA, This target is also commensurate with recommendations of the President's Commission on Americans Outdoors regarding the need for outdoor recreation and aesthetic environments. The goal should be to move fluvial ecosystems as many steps as possible from the negative side of the habitat quality index toward the positive side through rehabilitation, creation, or full restoration.
Given a target total of , miles, what are the priorities for fluvial restoration? Prioritization should be based on both human and ecological values, as suggested in Chapter 3 see Figure 3.
Restoration measures that save money or human lives as well as ecosystems should be undertaken as quickly as possible. These include floodplain and riparian zoning, soil conservation in lieu of channel or reservoir dredging, removal of flood-prone structures, razing of unsafe dams, and reduction of government subsidies that promote overgrazing or deforestation of riparian zones.
The tax dollars saved by these measures should be applied to other restorations that may not have offsetting economic benefits in the short term, but have high ecological or human values in the long term: chief among these should be preservation of biodiversity through preservation and restoration of critical aquatic habitats.
Prioritization on the basis of preserving biodiversity is likely to include a range of stream and river sizes throughout the country. For example, there are springs and small streams in the arid West where populations of several species of endangered desert pupfish occur. The number of species of fishes and mollusks generally increases with stream order, arguing for preservation and restoration of segments of large rivers.
One group of small fish, the darters, reach their highest number of species in streams and midsized rivers of the Tennessee drainage, whereas the species richness of aquatic insects is probably greatest in headwater streams. It is especially important that portions of large rivers be restored, for several reasons. Because many miles of streams coalesce into relatively few miles of mainstem rivers, large rivers are relatively uncommon.
Large river-floodplain ecosystems were disproportionately degraded because of their value for a variety of human uses, and the resultant concentration of human populations and development.
Of all wetland types, bottomland and hardwood forests along the Lower Mississippi River have suffered the greatest diminution through leveeing, drainage, and clearing see Chapter 6. Small streams receive some degree of protection by virtue of being located in federal or state forests, parks, and other types of protected land, but there are few programs for the protection of larger rivers, as Benke points out.
Nonstructural techniques can be broadly defined as any restorative method that does not involve either physical alteration e. Rivers and streams are resilient and can sometimes recover if the stress is removed and they are simply left alone. During 30 years of benign neglect following the clear-cutting of the surrounding forest and floating huge volumes of logs down the river to Lake Michigan, the ecosystem began to recover.
Although simple neglect has worked in a few instances, it is not likely to achieve much restoration on a national scale, especially on larger streams and rivers where there are multiple stresses, competing uses, and down-stream effects from upstream disturbances. Nonstructural techniques include administrative or legislative policies and procedures that stop or regulate some activity, such as withdrawal of water from a river or land use practices that degrade fluvial systems.
Reserving flow or reclaiming flow for in-stream uses fish, wildlife, outdoor recreation is an example of a legal approach to restoration in regions where water is in short supply and fully committed to withdrawals for crop irrigation, stock watering, or public water supply. Although long regarded as primarily a problem in the arid West, the issue of in-stream flow is being joined elsewhere. Droughts such as the — drought in the Upper Mississippi Basin saw many municipalities asking for permits to withdraw virtually the entire flow of some rivers e.
There is a need to amend the appropriative doctrine that is the basis of water law in the West so that flow is reserved for in-stream uses of water for fisheries and other aquatic life, boating and canoeing, aesthetics, and environmental purposes Lamb and Doerksen, The existing water laws have two primary principles: 1 first in time is first in right, and 2 beneficial use of water is the basis of the right.
Beneficial use in the past meant diversion for agriculture, industry, and municipal water supply. When water is scarce, those who established their appropriative rights last must stop using water until the needs of the more senior users are satisfied. In , Montana became the first western state to provide for the legal acquisition of a water right for in-stream uses; since then, 13 states have followed suit Lamb and Doerksen, Although all states except.
Box 5. The Pere Marquette PM and its tributaries flow through approximately miles of the northern third of Michigan's lower peninsula before emptying into Lake Michigan at Ludington. One of the few remaining free-flowing cold-water rivers in the contiguous United States, the PM has not only never been dammed, but is also extraordinarily clean and free from development despite a spate of ecologically devastating timber practices in the latter part of the nineteenth century.
The history of the PM includes multiple use and periodic stress on the ecosystem, yet the watershed has emerged remarkably intact. Indians, timber barons, canoeists, trout fishermen, and others have all used the PM, and the river seems to have evolved both because of and in spite of humanity's changing needs.
The timber industry's exploitation of the Pere Marquette region was so encompassing and voracious that in the early s experts pronounced the river "dead. Subsequent ramifications included significant changes in runoff due to widespread brush fires and abortive attempts at agriculture. The land, once cleared, was of little use to the timber industry, so much of it eventually reverted back to state ownership due to tax delinquency.
The region's sparse population meant that after the exodus of the loggers, the river suffered little human stress. Remarkably, the ecosystem flouted reports of its demise and began to recover.
Local inhabitants and the federal government began taking an active interest in the river's restoration. Mass replanting of cutover lands throughout the area by the Civilian Conservation Corps during the Depression led, in , to the creation of the Manistee National Forest, a federal holding covering a considerable portion of the PM watershed. With increased use of the river by sportsmen, the federal government assumed a more prominent role in stocking and managing the fishery.
The most ecologically significant governmental maneuvers include the planting of salmonids in the PM tributaries and several controversial attempts to control. Salmon were introduced both for their sport-fishing value and to control the overabundance of alewives in Lake Michigan. Many trout fishermen complain, however, that the annual salmon spawning run up the PM destroys trout habitat and leaves the banks of the river strewn with dead and rotting salmon.
The sea lamprey made its way into the river as a result of seagoing shipping traffic on the lake. Eventually the infestation reached such dramatic proportions that the Department of Natural Resources resolved to control proliferation through periodic applications of 3-trifluoromethylnitrophenol TFM , an effective lamprey larvicide. Use of TFM did bring the lamprey population under control, but under certain water quality conditions it is also toxic to mammals, fish, and insects.
As a result, fish habitat deteriorated and fish abundance decreased. Alternative attempts at lamprey control included the construction of an electric weir to deter lamprey movement upriver, but the weir is currently not in service due to detrimental effects on steelhead migration.
Designation of the PM as both a natural and a scenic river has substantially increased its use by sportsmen and canoeists. Canoe traffic over the last 20 years has risen from perhaps canoes per week to more than per day during tourist season. Expanded human use including increased fishing has, in turn , affected the aquatic habitat, and trout and salmon populations have declined further. Creel limits have been drastically reduced over the past 25 years, and canoe traffic is now regulated by the U.
Forest Service. The Pere Marquette, though greatly changed, remains freeflowing, clean, and remarkably resilient. Rather than treating it as a resource to be exploited for some human endeavor, most of the PM's management involves maximizing its potential as aquatic habitat and as a scenic river while controlling commercial and residential development. New Mexico have some sort of in-stream program, acquisition of a right to in-stream use is especially effective because 1 the in-stream use passes all tests of legal legitimacy and the terms of the right are spelled out; 2 the in-stream use has a priority date, so that it is superior to all subsequent rights; and 3 even if the in-stream use is junior in right to other uses, the junior user can legally prohibit a.
In the eastern states, water quality rather than water quantity was the problem historically, and the relevant legal principle was "reasonable use" by riparian landowners, if that use did not interfere with the water rights of others along the river or stream Ausness, Later, many eastern states moved toward a permit or water-allocation system, to provide water to people who do not own riparian lands Lamb and Doerksen, Most eastern states have some statutory provision that can be used to reserve stream flows in time of shortage, but these vary widely in effectiveness and application.
The doctrine of Federal Reserved Water Rights allows the federal government to reserve in-stream flows to fulfill the purposes of certain federal lands national forests, parks, wildlife refuges, and wild and scenic rivers; Lamb and Doerksen, The priority date for these uses is the date on which action was initiated to create or change a federal reservation. The doctrine legitimizes in-stream uses of water that might not be recognized under existing state laws, and it gives these uses much earlier priority dates than would most state laws.
It applies to future as well as present needs and might cause in-stream uses to supersede other, more senior rights. As of , claims under the doctrine had been for very small amounts of water Lamb and Doerksen, , and it appears that this relatively new legal tool for maintenance or restoration of in-stream flows could be put to much greater use. Once the legitimacy of in-stream uses has been established, the next task is to determine what flows those uses require.
A relatively simple but crude approach that is appropriate during preliminary planning for a project or to provide a baseline of protection is to determine the minimum flows necessary for fisheries, canoeing, or other in-stream uses. Examples include the lowest flow on record, flows equaled or exceeded 90 percent of the time, or the point at which the wetted perimeter begins to fall sharply with small reductions in flow Trihey and Stalnaker, Incremental methods estimate the quality and quantity of fish habitat at each increment of flow and are more suitable where the goal is to restore or upgrade fish populations and where water is in great demand.
It is labor-and data-intensive and requires field measurements and hydraulic modeling, but it provides fairly precise answers to the question: What is gained by a given increment. Its weakness is that it is species specific and inapplicable to multispecies assemblages Hughes et al. It is most applicable to western streams where it was first developed. These streams are usually occupied by a small number of highly valued sport species trout and salmon whose use of particular habitats under different flow regimes can be visually determined in the relatively shallow, clear waters.
Wiley et al. An issue related to in-stream flow is the flow regime, or pattern of high and low flows, particularly below hydroelectric and irrigation supply dams. Daily fluctuations occur below hydroelectric dams, which are often used to supply power during periods of peak demand for electricity. The flow below irrigation storage dams is often the reverse of the normal annual pattern, with minimal flow during the wet months because water is being stored behind the dam, and more flow during dry periods, if there is return flow from the irrigated lands.
A nonstructural means of securing more natural flow regimes is to renegotiate release schedules when permits and licenses come up for renewal. Echeverria et al. The inverse of the water shortage issue is the issue of floods on floodplains. Johnston Associates describe four eras in the history of floodplain management: 1 the structural era, to ; 2 a turning point in the s; 3 the environmental decade, to ; and 4 maturation in the s.
Congressional attitudes have responded to growing urbanization and environmental awareness by shifting emphasis from major flood control and other water resource projects to risk management, environmental improvement, protection of ecosystems, and urban water quality. What started as separate programs for water resource projects, disaster assistance, and environmental quality has become better integrated, and the focus in the s was on implementation of policies and programs rather than new legislation or institutional changes.
The final trend has been decentralization of the federal role and greater sharing of the responsibility for floodplain management with state and local governments, in response to federal deficit reduction policies and growing technical expertise at the state level Johnston Associates, Examples of nonstructural methods of floodplain management that promote preservation or restoration of floodplains are adoption of regulatory floodways, purchase of easements to prevent construction, and purchase of land and removal or relocation of structures.
Any development within the floodway including cumulative developments that would increase the height of the year flood a flood whose probability of occurrence in a given year equals 1 percent by more than 1 ft is prohibited. Some states have much more stringent requirements for their floodways: Massachusetts permits no increase in water levels, Wisconsin allows only 0.
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