Wednesday, June 6, 2012

Estimation of Turbine passage survival of juvenile American shad, Alosa sapidissima, by different methods for practical application

Paul Heisey — Wed, 06 Jun 2012 13:50:00 PDT

The impetus for our presentation is primarily three-fold: (1) present survival estimate of juvenile American shad, Alosa sapidissima recaptured and examined after passage through a relatively large Francis turbine (hydraulic capacity > 6,000 cfs) at Conowingo Hydroelectric Station, MD and its implications on restoration of the species to the Susquehanna River, (2) compare fish survival derived from a blade-strike equation, and (3) applicability of using literature based survival estimates for multiple fish size and species without conducting a field study at a hydroelectric project. Limited published data exist on passage survival of juvenile American shad through relatively large Francis units. Survival probability of juvenile American shad (106 to 142 mm total length, average 119 mm) was estimated while passing through an aerated Francis turbine using the HI-Z Tag recapture technique. The experiment utilized 138 hatchery reared juveniles released into the turbine and 76 fish released downstream of the turbine discharge as controls. The turbine passage survival was estimated at 89.9% with 90% (Î± = 0.10) confidence intervals of ± 5.5%. This estimated survival is within the range (83.5-94.7%) of empirically determined (HI-Z Tag) estimates for similar sized Francis units (runner diameter >110 in, buckets 13-17). While blade-strike derived survival estimates generally show a close correspondence, particularly for salmonids, with empirically determined estimates for Kaplan type turbines, it appears that some differences between the two estimates may occur for clupeid passage through Francis turbines. For the tested Francis turbine at Conowingo, the survival estimate from the blade-strike equation was approximately 5% higher than the empirically determined estimate of 89.9%. Blade-strike equation generated survival estimates maybe higher than empirical estimates because they do not account for potentially higher mortality due to the sensitivity of juvenile shad. Across all Francis type turbines, EPRI field estimated survival of small sized fish was 92%, relatively similar to that estimated herein. While the application of published and/or mathematically derived survival estimates to non-studied sites is encouraged and is useful, caution should be exercised to include only field studies with acceptable control mortality (handling, tagging, and recapture). We suggest control mortality be ~20% for clupeids and ~10% for other species. The life stage and sensitivity of a given species also needs to be considered when using mathematically derived estimates.

Barotrauma in Juvenile Salmonids Exposed to Simulated Hydroturbine Passage: pathways, management implications and applications

Richard Brown — Wed, 06 Jun 2012 14:50:00 PDT

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Barotrauma (e.g., swim bladder rupture, hemorrhaging, emboli and exopthalmia) resulting from rapid decompression can be a major source of injury and mortality during turbine passage. The mechanisms of these injuries can be due to expansion of existing bubbles or gases coming out of solution; governed by Boyle's Law and Henry's Law, respectively. It appears that the majority of decompression related injuries observed in juvenile salmonids exposed to simulated turbine passage are due to the expansion of existing bubbles in the fish, particularly the expansion and rupture of the swim bladder. This information is particularly useful for fisheries managers and turbine manufacturers. Reducing the rate of swim bladder ruptures by reducing the frequency of occurrence and severity of rapid decompression during hydroturbine passage could reduce the rates of injury and mortality for hydroturbine passed juvenile salmonids. However, there is little information about how other species, with varying physiological and morphological characteristics (e.g., type of swim bladder), will be influenced by changes in pressure. The implications for fisheries management, hydro management and development and broadening the range of understanding of barotrauma in both salmonids and non-salmonid species will be presented.

Pawtuxet Falls Restoration: Lessons from Narragansett Bay's Largest Dam Removal

Andrew Lipsky — Wed, 06 Jun 2012 16:05:00 PDT

In August, 2011, the Pawtuxet River flowed freely into Narragansett Bay, R.I., for the first time in more than 200 years. The removal of Pawtuxet Falls Dam was the culmination of years of planning and permitting by the Pawtuxet River Authority, Narragansett Bay Estuary Program, and a partnership of more than a dozen state, federal and non-profit organizations, with technical support provided by EA Engineering, Science and Technology. The project restored seven miles of spawning habitat for American shad and river herring to Narragansett Bay's third-largest tributary. The project team overcame a number of significant design challenges, including public concerns regarding aesthetics and historic preservation; contaminated sediments; poor construction access; concerns about flood vulnerability; and an unprecedented regulatory scale. We'll share innovative solutions and adaptive management approaches that resulted in successful outcomes, and can be applied to similar projects throughout the country.

Removal of the Merrimack Village Dam

Mark Wamser — Wed, 06 Jun 2012 16:25:00 PDT

For decades, a dam was located on the Souhegan River, roughly 1,800 feet upstream of its confluence with the Merrimack River. The dam, known locally as the Merrimack Village Dam (MVD), was located in a highly visible location in Merrimack, NH. The former owner of MVD, Pennichuck Water Works (Pennichuck), is a water supply company who purchased the dam in the 1960s as a potential water supply source, but it was never developed. In the mid 2000s, the New Hampshire Department of Environmental Services (NHDES) who regulated dam safety, issued Pennichuck a letter highlighting several deficiencies with the dam requiring extensive costs. NHDES also indicated that as an option to repairing the dam, they offer a program to assist owners with removing dams. After weighing the cost associated with dam repair, on-going liability, on-going operation and maintenance costs and the ecological restoration benefits, Pennichuck opted to conduct a feasibility study to determine if it was practical to remove the structure. Pennichuck applied and received numerous grants to help partially defray the cost of conducting a feasibility study and the eventual removal of a 20-foot high, 180 foot-long concrete and stone masonry dam in 2008.

Session A6 - Operations and Maintenance of Fishways for River Herring in New Hampshire Coastal Rivers

Cheri Patterson — Wed, 06 Jun 2012 16:05:00 PDT

Operation, maintenance, and field modification are critical for effective performance of upstream and downstream fish passage systems. This talk draws on 35-years of experience operating, maintaining, and modifying upstream fish passage systems for river herring in coastal New Hampshire rivers. Specific topics include planning for seasonal operations, staffing, costs, maintenance, as well as preferences and suggestions by professionals responsible for overseeing and maintaining upstream fish passage systems. The New Hampshire Fish & Game Department owns, operates, and maintains seven upstream fish passage systems in coastal New Hampshire rivers where river herring are the target species for upstream passage. These fishways are primarily denil, but also pool-and-weir and Canadian step-weir (removed in 2010) that are operated and maintained each spring for upstream passage of river herring. This talk discusses the experience of staff maintaining, modifying, monitoring and operating these fishways based on practical experience to maximize fish passage with the actual designed structure.

Session C6 - The Effects of Dam Removal on the East Branch of the Eightmile River, Connecticut

Barry Chernoff — Wed, 06 Jun 2012 15:45:00 PDT

The hydrography of the East Branch of the Eightmile River has been modified since the 1720's when a dam was constructed on the Zemko property. While the dam has occasionally fallen into disrepair, the dam has largely been intact for more than the last hundred years. In 2006, the water in the impoundment behind the dam was drawn down and the dam was completely removed by fall 2007; a rocky connector was constructed between the portion above and below the former dam. We have surveyed fishes, benthic macroinvertebrates (BMI), water chemistry and physical parameters from 2004 through 2010 at the former dam sites and at a control site five river miles downstream. The biological communities have changed dramatically since drawdown and dam removal. The inter-annual variation of the communities in the vicinity of the dam site is significantly higher than at control sites. The data from both fish and benthic macroinvertebrates indicate that the patterns of change or "recovery" differ in the sections of river above and below the dam. We will ask whether there has been recovery from dam removal in this small section of stream. We will also discuss the concepts of resilience and adaptation in relation to the functioning of the streams.

Session A6 - Methodologies for River Herring Passage Evaluations, Monitoring, and Assessment of Population Restoration Success

Alex Haro — Wed, 06 Jun 2012 15:45:00 PDT

Although numerous structures have recently been built to provide upstream and downstream passage of river herring at migratory barriers, few have been quantitatively evaluated for their performance. Basic monitoring of these passage structures by simple visual counts of fish also tends to be relatively qualitative in nature, and often inaccurate. The scale of passage structures for river herring offers many opportunities for comprehensive evaluations and monitoring that are often not feasible with other anadromous fishes. Several technologies have been developed to perform more quantitative evaluations and accurate monitoring of passage structures and river herring runs, ranging from mark-recapture studies, automated video recording, and telemetry; these methods are reviewed and summarized in terms of level of effort, cost, and data return. Newly-developed numeric methods for analyzing data to estimate attraction, spatial/temporal passage performance, and assessment of passage performance relevant to restoration goals are also described.

Session C6 - Calco Dam Removal - Commencing the Restoration of the Raritan River Watershed, New Jersey

John Jengo — Wed, 06 Jun 2012 15:25:00 PDT

An innovative Natural Resource Damages (NRD) Settlement Agreement between the New Jersey Department of Environmental Protection (NJDEP) and El Paso Corporation, formulated to address claimed lost ecological services caused by former industrial operations discharging into several New Jersey rivers, specified the removal of three lowhead dams (Calco Dam, Nevius Street Dam, and Robert Street Dam) on the main stem of the historic Raritan River in central New Jersey. The most downriver dam (Calco Dam), a former chemical dispersion weir located in the vicinity of Bound Brook, was successfully removed between July 18 - August 2, 2011. The dam was initially breached over a specific modeled width, which allowed the upriver impoundment to completely drain by the end of the working day without triggering adverse sediment transport. The subsequent two weeks of work involved removal of the dam's deeper infrastructure, careful severing of the dam where it was underlying a historic 175-yr old canal towpath berm, and removal of all concrete and rebar from the river. The final aspects of the project included grading of the river bed and restoration of embankments back to their pre-dam configuration. This dam removal re-opened 6.1 miles of the Raritan River and 1.5 miles of the Millstone River, in addition to the lower reaches of several significant tributaries, which have widespread sandy and pebbly gravel river bed substrates, ideal spawning habitat for anadromous fish species such as American shad that formerly numbered in the millions. The Robert Street Dam, a sheet-piled supported structure encasing an older concrete gravity dam located seven miles upriver of the former Calco Dam, is slated for removal in July-August 2012, which will then be followed by the breaching of the Nevius Street Dam, thus satisfying the NRD Settlement terms and completing New Jersey's most significant river restoration project to date.

Session A6 - Fish Passage, Ecohydrology, and More: A Comprehensive Approach to Protect River Herring in the Wild and Scenic Taunton River Wa

Alison Bowden — Wed, 06 Jun 2012 15:25:00 PDT

The Taunton River, a ~500 sq mi watershed on Southeastern Massachusetts' coastal plain, hosts one of the largest river herring runs in New England as well as numerous rare aquatic and wetland species. The River received Federal Wild and Scenic designation in 2009, but is located in the heart of the fastest developing region of Massachusetts. Protecting the Wild and Scenic values for future generations demands a comprehensive approach to watershed protection as well as linking freshwater, estuarine, and marine conservation strategies for migratory fish, which have great cultural as well as ecological significance in the watershed's 43 communities. With multiple public and private partners, The Nature Conservancy has collected detailed baseline data on water use and water transfer throughout the watershed to develop a water balance tool; assessed hydrologic conditions and ecological indicator conditions in >100 sub-watersheds to target management strategies; designed 6 projects to demonstrate innovative water management practices; and identified the highest priority dams, road-stream crossings, and parcels of land for conservation action. Collectively, we are working on removal or fish passage at 7 dams, protection of over 2000 acres of land in the watershed, with much more in the pipeline. These site based strategies are linked with statewide policy efforts such as establishing streamflow standards and easing permitting of restoration projects, and regional scale research and fisheries management to reduce bycatch of river herring in ocean fisheries.

Session C5 - Guidelines For Assessing Sediment-Related Effects of Dam Removal

Timothy Randle — Wed, 06 Jun 2012 14:30:00 PDT

Dam removal is becoming more common in the United States as dams age and environmental concerns increase. Sediment management is an important part of many dam removal projects, but there are no commonly accepted methods to assess the level of risk associated with sediment stored behind dams. Therefore, the interagency Subcommittee on Sedimentation (SOS) is sponsoring the development of a decision framework for assessing sediment-related effects from dam removals. The decision framework provides guidance on the level of sediment data collection, analysis, and modeling needed for reservoir sediment management. The framework is based on criteria which scale the characteristics of the reservoir sediment to sediment characteristics of the river on which the reservoir is located. To assist with the framework development, workshops of invited technical experts from around the United States were convened October 2008 in Portland, Oregon and October 2009 in State College, Pennsylvania. The decision framework developed at these workshops is currently being validated with actual dam-removal case studies from across the United States including small, medium, and large reservoir sediment volumes. This paper provides the latest thinking on key components of the guidelines. The paper represents contributions from over 26 entities who have participated in the development of the guidelines. After completion of the case study application, the framework will be finalized and published.