Staff outlines drought management plan, design-standard changes and AWS-tied water reuse project

Utilities staff presented a block of items at the May 15 work session, telling the board a DEQ permit condition required the county to adopt a drought management plan and outlining proposed changes to design standards and a countywide water-reuse project tied to data center proffers.

"Last year, when the Lake Mooney withdrawal permit was reissued by DEQ, they did require the drought management plan as a provision in the permit," John (last name unclear in the transcript), a utilities staff member, told the board. Staff said the plan largely mirrors existing county code but updates the trigger conditions (using days of available water in the reservoirs and DEQ drought declarations). The plan outlines escalating stages from voluntary commercial and residential reductions to mandatory restrictions and an emergency stage that would restrict use to essential human consumption and health reasons.

Board members asked about enforcement and outreach. Staff said mandatory restrictions would be enforced through standard county code violations and notices, and that automated meter reading could help identify excessive usage; staff recommended broader public notice through utility bills and email as well as social media.

On design standards, Chris Adderich, Director of Utilities, described two main proposed changes: updating the maximum allowable sewer depth for safety and field operations and modernizing the as-built submittal process for GIS accuracy. Adderich explained the county currently allows sewer depths to 30 feet but said trenches deeper than about 18'20 feet present significant confined-space and rescue risks; staff proposed aligning the manual with industry safety practices.

Staff also proposed revising a 1990 low-pressure-sewer policy so low-pressure grinder-pump systems would no longer be used for new subdivisions while remaining an option for failing drain fields or some commercial applications. Adderich noted grinder pumps can cost homeowners about $10,000'$15,000 to replace and are prone to failures; staff said the policy change will return to the board for action.

On reuse water, staff described proffers from Amazon/AWS at the Potomac Church site. Chris Edwards (Utilities) said AWS agreed to construct a reclaimed reuse-water system sized to the wastewater plant's capacity so future users can connect. DEQ required the county to upgrade the treatment plant to a more refined "Level 1" standard for reuse; staff estimated that work at roughly $75 million with a prior $15 million design request included in the budget cycle for initial design work. Edwards said the draft water services agreement calls for the developer to fund required improvements and that staff hopes reuse lines and rates will be in place to support connections by 2027'28.

Staff also presented capacity estimates: current dry-weather flow at Aquia is about 4.5 million gallons per day (gpd); expected returns from data centers could add roughly 1 million gpd; preliminary conveyance changes could give roughly 6 million gpd available for reuse connections. Potomac Church requested 0.5 million gpd; other proposed campuses (Stanford Technology Campus) could require 4'6 million gpd depending on specific users.

Next steps: staff will return with the drought-management plan and code updates for adoption, bring the low-pressure-sewer policy to the board for consent action if the board wishes, finalize design-standard amendments (some administratively approvable), and bring a water services agreement and the Level 1 design contract back to the board for consideration.