Our familiarity with 316b compliance stems from over 50 years of combined experience with fish protection at cooling water intakes. The strategies we develop for our clients rely on the integration of our core competencies in fisheries biology, fisheries engineering, hydraulic engineering, consulting, design, and research and development. Our engineers and scientists work closely together to ensure designs are biologically effective, feasible to construct, operate, and maintain, and are cost effective—all while meeting regulatory requirements.

Ongoing 316(b) Research and Development

Our team acknowledges the importance of weighing costs with minimizing the adverse environmental impact on aquatic life in the waterways around cooling water intakes—the basis for section 316(b) of the Clean Water Act. That’s why we’ve been actively involved with the 316(b) rulemaking process on behalf of the electric power industry via EPRI and Utility Water Act Group (UWAG). Not only have we compiled and presented the results of five comprehensive fish protection technology research studies to the Environmental Protection Agency (EPA), we also provided technical comments on Phase I, Phase II, and Phase III 316(b) rules, the current existing facilities rule, and the associated Notice of Data Availability (NODA).

Our dedication to developing state-of-the-art fish protection systems and keeping abreast of all ongoing research efforts in 316(b) compliance means our clients benefit in areas like:

  • Research and development, evaluation, and design of fish screening facilities at large water withdrawals 
  • Optimization studies
  • Impingement and entrainment sampling
  • Engineering feasibility studies
  • Biological modeling and assessment, including hydraulic model studies, laboratory, and field biological evaluations
  • Compliance strategies
  • Study design and planning
  • Laboratory and in-situ pilot testing of fish protection technologies
  • Alternative technology evaluations, such as research on the effectiveness of behavioral barriers for preventing fish impingement
  • Cooling water intake systems (CWIS) alternative technology feasibility  and costs assessments under the § 316(b) Phase II Rule for over 170 power plants located throughout the U.S. and continue to satisfy § 122.21(r) requirements
  • Information Management
  • Agency Consultation
  • Expert Testimony
  • QA/QC Plans

Further Reading

Recent Projects

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In order to meet screen velocity requirements of the Clean Water Act 316 b rule, American Electric Power has investigated the possibility of replacing the Clifty Creek Power Plant traveling water screens with an array of cylindrical wedgewire screens in the cooling water intake forebay.  The site on the Ohio River experiences significant siltation, and there were concerns about associated vulnerability of the wedgewire screens. 

Alden performed flow modeling to evaluate this possibility, and provide possible solutions. The model scope included river flow both upstream and downstream of the intake structure and flow within the intake structure. To model the geometric details of the system accurately, a field survey conducted by Alden was performed prior to the flow modeling efforts. The flow study included 2D and 3D numeric modeling, as well as scale physical modeling.

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Environmental Management & Compliance | Civil Infrastructure
Clifty Creek Power Plant Intake Modification

investigation of the hydraulic, thermal, and sediment dynamics within a cooling water intake forebay on the Ohio River, including both 3D numeric and physical modeling

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The Electric Power Research Institute (EPRI) has funded laboratory studies at Alden on the biological efficacy of fine-mesh screens for safely collecting larval and juvenile fish. However, little information existed on the effects of fish return systems on larval or early juvenile survival. Alden performed two years of laboratory evaluations on factors affecting larval fish survival in fish return systems at cooling water intake structures (CWISs). The project provided the additional data necessary to determine the overall biological efficacy of larval fish collection and return systems. The study was designed to evaluate the effects of velocity, drop height, length, drops and bends on larval fish survival through a fish return system.

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Environmental Management & Compliance | Natural Resources & Environmental Planning
Fish Survival in Fish Return Systems at Cooling Water Intakes

Alden performed two years of laboratory evaluations on factors affecting larval fish survival in fish return systems at cooling water intake structures

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In 2012, Alden developed a report providing an updated review of the state of knowledge on fish protection technologies for use at power plant cooling water intake structures (CWISs) to meet requirements of §316(b) of the Clean Water Act (CWA). In general, power generating facilities have some flexibility in selecting fish protection technologies. The information provided in the report can be used by power generators, resource managers, and permitting agencies to determine the potential for different fish protection technologies to reduce impingement and/or entrainment losses at CWISs. Fish protection technologies are generally grouped into five functional categories—physical barriers, collection systems, diversion systems, behavioral guidance devices, and flow reduction. The performance, operational and maintenance issues, and documented installations of each technology in each functional category were described in the report. The results of the review indicated the importance of site-specific factors to the biological effectiveness and engineering practicality of a technology.

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Environmental Management & Compliance | Natural Resources & Environmental Planning
Development of the EPRI Technical Reference Manual for Fish Protection at Cooling Water Intake Structures

A report was developed to provide an updated review of the state of knowledge on fish protection technologies to meet 316(b) requirements