Port Townsend to hire consultant to reevaluate dam at Lord’s Lake

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A dam at the Lord’s Lake Reservoir, Port Townsend’s main source of water, is set to be inspected for seismic stability following a concerning seismic discovery in 2020.

An inspection of the reservoir by Washington state’s Dam Safety Office rated the lake’s East Dam to be in poor condition, indicating the dam didn’t meet minimum stability requirements for seismic loading — or how a structure can handle an earthquake.

Following the report, the Dam Safety Office is requiring the city of Port Townsend to hire an engineering consultant to assess the reservoir. The city will choose someone from GeoEngineers, an engineering and Earth science consulting firm, to evaluate and possibly develop improvement alternatives to make sure the East Dam can handle earthquake damage in the future.

The Port Townsend City Council unanimously approved a measure to hire the engineering consultant during its Monday business meeting.

The consultant will perform a preliminary analysis of existing data, investigate the geophysical field, analyze and model field investigation data, develop slope stabilization alternatives if data indicates a problem exists, advance alternative designs, and develop a permitting scope of work.

The analysis work isn’t expected to be completed until June 2023.

The primary objective of the investigation is to evaluate the current state of the East Dam and potential breach risks, then prepare alternatives to stabilize the dam if need be.

The Dam Safety Office determined that the East Dam is eligible for the High Hazard Potential Dam Rehabilitation Grant Program from the  Federal Emergency Management Agency. Port Townsend city staff have requested $86,900 in funding from FEMA and has budgeted $47,000 to meet match requirements to qualify for the federal grant. The FEMA grants are expected to be released in the fall.

Dam analysis will not begin until the city confirms funding from the FEMA grant and other sources.

The city could eventually pay an estimated $4 million to retrofit the dam, according to the city.