Vancouver Seismic Evaluation

DOWL provided inspection and seismic evaluation to the City of Vancouver for four elevated steel water reservoirs and an at-grade concrete reservoir that range in size from 250,000 gallons to 10,000,000 gallons. DOWL worked closely with the city to determine project objectives and desired performance for the reservoirs, which were built between 1945 and 1968. The level of effort for each structure was carefully managed to provide the maximum amount of value to the city.

For the at-grade concrete reservoir, a simple fatal flaw analysis determined that retrofit of the structure was not a cost-effective solution. In contrast, the three multi-column elevated steel water towers were identified with anchorage and bracing deficiencies, and analysis at one of the other elevated reservoirs included nonlinear time history analysis to evaluate a seismic friction-damper retrofit system.