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Takeaways from the Alden Forum 2017: Hydropower and Fish Passage
On May 17-18, Alden hosted a forum on hydropower and fish passage that was attended by more than 45 industry, state and federal agency, and NGO representatives.  The forum focused on fish passage issues typically encountered at projects in the Northeast and Southeast U.S.  It was particularly timely because the relicensing of 231 hydropower projects will occur throughout the U.S. between 2018 and 2025, with an additional 100+ projects to be relicensed between 2026 and 2030.  More than half of these projects are located in the Northeast and about 30% are located in the Midwest and South.  All of the projects will need to address a variety of environmental issues associated with their operation and, in many cases, mitigation alternatives will need to be developed to reduce or minimize impacts to affected resources.  The two most prevalent environmental issues addressed during relicensing typically are instream flows and fish passage.  Fish passage can be problematic with respect to biological, engineering, and project operation considerations. It can also be very costly.  Based on these issues, the goal of the Forum was to bring together regulatory and resource agencies, NGOs, consultants, and project owners to exchange information and have relevant discussions on important environmental issues (primarily fish passage) addressed during the FERC relicensing process.


Attendees at the Alden Forum 2017

Attendees at the 2017 Alden Forum on Hydropower and Fish Passage


Based on presentations given by the various speakers, the primary takeaways from the forum include the following:


  • Industry non-profit organizations (EPRI and the Hydro Research Foundation) are very active in supporting research related to hydro power impacts and how they can be addressed and mitigated.

  • The Low Impact Hydro Institute has been making substantial changes to its low impact certification process to address the needs of hydro project owners and stakeholders with respect to the protection of environmental resources.

  • The U.S. Department of Energy’s waterpower program has been very active with research at its national laboratories, with a focus on supporting sustainable hydro operation and development using tools and data that identify environmentally-friendly technologies and techniques.

  • Federal resource agencies, U.S. Fish & Wildlife Service and National Marine Fisheries Service, have developed documents for fishway design, operation, and evaluation. NMFS is seeking the development of an evaluation database of fish passage facilities with hydro operator input. 

  • Turbine entrainment and mortality is a major issue that needs to be addressed during relicensing and will require mitigation (downstream fish passage) at many projects. Desktop study methods have been developed for estimating entrainment and turbine mortality using existing information and data in lieu of expensive field studies. Specific study methods may vary from site to site or depending on project design, management objectives, and target species (e.g., resident species vs. migratory species). Impacts from turbine entrainment and mortality are still poorly understood for resident fish, and the need for mitigation can be difficult to determine.

  • There are a wide variety of upstream and downstream fish passage technologies that can be considered for installation. Technology selection will depend on various biological and project design considerations. Post-installation effectiveness testing is often required and often shows considerably more research and development is needed to optimize the biological performance of many new and established technologies.

  • Upstream and downstream passage of American eel is a major issue for East Coast projects. Upstream passage technologies are effective and relatively inexpensive, but proper siting of eel ladders needs to be investigated before installation, to ensure upstream migrants can locate entrances. Downstream passage of adult eels is more problematic and will typically involve some type of entrainment protection with one or more bypasses. The potential need for narrow bar spacing to reduce entrainment can have major implications for project operation.

  • CFD modeling has become a valuable tool in the design and siting of upstream and downstream fish passage systems. It provides the ability to assess hydraulic conditions with respect to fish behavior for multiple alternative designs, and is relied on by both project owners and resource agencies.

  • Post-installation effectiveness testing typically will be required for most upstream and downstream fish passage installations. There are several methods that can be employed, and many considerations that need to be addressed for a study to be successful and provide the information needed to determine fishway performance.

  • Project owners have many issues to address during relicensing, with fish passage often being the most difficult and costly. Considerations for impacts to power generation and economics need to be factored into the selection of fish passage technologies in a meaningful way. Addressing fish passage at small hydro projects can be particularly challenging, because margin of economic sustainability is very small.

 

Agencies and companies attending the Alden Forum 2017

Cake consumed during a break at the 2017 Alden Forum, showing companies and agencies in attendance


The format and content of the forum was highly rated by the attendees and led to many in-depth and productive discussions.  The setting appeared to be more conducive to open dialogue among all of the participants compared to typical relicensing meetings and agency consultations.


Planning for additional forums addressing other relevant topic areas related to fish passage and other environmental issues is underway by Alden staff, and may include hosting events in other regions of the U.S.


 

 




 





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Avatar  Alan Potkin last year

No mention of what may be the 600 lb gorilla in the hydropower/fisheries mitigation room: the conversion what may well be 100 km of waterway immediately upstream of the dam from it's previous "lotic", i.e., flowing or riverine hydrology, to a radically different "lentic", i.e., essentially lacustrine or lake-like hydroecology. So even if upstream migrant somehow make it through the fish ladders, once past them they may well have to cope with a limnological situation for which they have no evolutionary or adaptive history. In most cases, say by comparison to the five or six salmonids and maybe a few non-salmonids of commercial aesthetic, and cultural significance that need to be mitigated in Northern/central California, Pacific NW, Alaska, and BC— I mostly work on the Mekong, and there are seldom fewer than 100 spp. from a dozen different taxonomic families, either resident or migrant, at any particular site on the mainstream. Of which very little is known of their detailed ecology.