Lincoln Reservoir buried under Cal Anderson Park (Image: City of Seattle)

Way back in the early aughts the north side of Cal Anderson Park was dominated by the open-air Lincoln Reservoir. In 2003 the city began a two-year project to bury it and give us the wonderful open spaces we enjoy today while keeping our drinking water neighborhood sourced.

For now the underground Lincoln Reservoir is holding water just fine, according to a Seattle Public Utilities spokesperson. However, an expensive retrofit project at the West Seattle Reservoir, designed by the same firm that did Lincoln, is slated to get underway this summer after “seismic deficiencies” were discovered in 2011 followed by extensive testing.

The West Seattle Blog reports that the 4-year-old West Seattle Reservoir under Highland Park needs a $7.6 million retrofit in order to withstand a major seismic event — one much stronger the 2001 Nisqually earthquake. SPU is also studying three other nearby reservoirs to determine if they’ll need retrofits, too. All told the projects could cost up to $30 million, according to SPU.

As of right now, Cal Anderson’s reservoir is not scheduled to undergo seismic testing as no potential design flaws have been raised be the original architects, according to an SPU spokesperson. In 2009 CHS reported on leaks discovered at the West Seattle Reservoir while Lincoln remained structurally sound.

The West Seattle reservoir was designed by the Denver-based firm MWH. The Lincoln Reservoir, designed by the firm Tetra Tech, is a major distribution point for the Cedar River pipeline which provides most of the potable water for central Seattle.

Meanwhile, the currently decommissioned Volunteer Park Reservoir is likely down for the count. SPU spokesperson Andy Ryan told CHS that the utility is continuing to evaluate the city’s drinking water supply in hopes that it can permenantly close the aging Volunteer Park and Roosevelt reservoirs. SPU is expected to make a final decision in 2015.