Electric Power Research Institute (EPRI)

Project Objectives

The Electric Power Research Institute (EPRI) is heading a large project to assess the condition of hydro power plants in the U.S. The project consists in the use of non-destructive techniques specifically aimed at evaluating the degradation mechanisms that may affect the durability of these structures.

The main objective was to develop a technical basis for future inspections of hydro power plants based on degradation mechanisms affecting different parts of these structures and associated risks.

SIMCO’s Scope of Work

SIMCO was hired by EPRI to develop a degradation matrix for the Robert Moses Niagara Power Plant located in Niagara Falls NY. This 70-year-old structure was selected mainly because of its significance and the large quantity of data available.

The recommendations provided by SIMCO will serve both as a reference guide and a technical basis for subsequent inspections and planning by the New York Power Authority (NYPA).

The investigation consisted in a visual inspection of selected areas of the structure, namely, the intake deck, the inner gallery and the dam face. The observations were used to identify active concrete degradation problems and determine the course of actions to limit their impact on the service life, operation and safety of the structure. The main observations, potential impacts and recommendations were all summarized in a risk-ranking degradation matrix.

The degradation matrix was developed within the project’s framework and covered the following tasks:

• Summary of relevant operating experience, i.e. inspection results, available from the owner
• Identification and description of the relevant degradation mechanisms (or combinations thereof)
• Estimation of the kinetics of these degradation mechanisms
• Assessment of the effect of degradation mechanisms on the service life, operation and safety of the different investigated concrete structures over the next 20-30 years
• Approached prognosis to 20-30 years suggesting frequency of inspections and preventive maintenance schemes

Results

• Reliable assessment of deterioration issues affecting the different elements of the hydro power plant
• Recommendations for the implementation of cost-effective corrective and preventive interventions to extend the service life for another 20-30 years