Why Washington's 2026 SGGP Change Puts Damage Prevention at Risk
Hydro‑excavation has long been one of the safest and most reliable methods for exposing underground utilities. By using pressurized water and vacuum extraction, contractors can daylight utilities without the risks associated with mechanical digging. The trade‑off is that the resulting slurry—soil mixed with water—must be disposed of at a permitted facility.
Across Washington State, and in much of the country, hydro‑excavation slurry is commonly accepted at sand and gravel pits operating under the Sand and Gravel General Permit (SGGP) issued by the Washington State Department of Ecology (DOE). These facilities are engineered to manage soil‑based materials, and for decades they have served as the primary, regulated disposal option for hydro‑excavation waste.
The 2026 Regulatory Shift
In February 2026, DOE revised the SGGP to exclude hydro‑excavation slurry from permitted materials, with the change scheduled to take effect in April 2026. DOE’s rationale was that the water used in hydro‑excavation constitutes “process water,” even though in nearly all cases the water is potable municipal water used solely to break up soil for safe excavation.
This reinterpretation created an immediate and significant threat to the availability of legal, permitted disposal sites. DOE did not provide any alternative disposal sites.
Industry Response and Advocacy
Chase Looker of Looker Properties in Puyallup, WA, and Clint Myers of Northwest Cascade Inc—both operators of SGGP‑permitted pits—brought the issue before the National Utility Contractors Association of Washington (NUCA of WA). Their concern was not about business operations, but about the broader implications for:
Damage prevention
Worker safety Statewide infrastructure reliability
I was asked to prepare a paper supporting continued acceptance of hydro‑excavation slurry under the SGGP. My focus was not on individual businesses, but on the public safety consequences of restricting disposal options.
Damage Prevention and Public Safety
The Common Ground Alliance (CGA) DIRT data shows that approximately 33% of utility damages occur because lines are unlocated or mislocated. I’ve seen this firsthand. My vacuum crew encountered a 16‑inch gas transmission line mislocated by more than six feet. Without a vacuum truck, that situation could have resulted in a mass‑casualty event. In June 2026, a construction company I support found a 2” gas line mislocated two different times at the same location. There was no damage to the lines. They were potholing to do a water tie in when the lines were found and not correctly located.
Hydro‑excavation is one of the few tools that can reliably turn the unknown into the known without endangering workers or the public.
Restricting disposal sites creates a cascade of risks:
Vacuum trucks spend more time traveling to distant facilities
Jobsite delays increase
Contractors face pressure to cut corners—not intentionally, but because the system leaves them no choice
Utility damages rise
Injuries and fatalities rise
When disposal becomes difficult or cost‑prohibitive, some operators may resort to illegal dumping, including near waters of the state—an outcome far worse than disposal at a regulated SGGP facility.
Environmental Reality: Slurry vs. Actual Wastewater
DOE does not allow sewer and contaminated stormwater or polluted stormwater to be disposed of at these same pits—materials that unquestionably require treatment at specialized facilities.
Hydro‑excavation slurry, by contrast:
Is primarily native soil
Uses potable water
Contains no industrial additives
Is materially similar to the soil already present at the pit
National Implications
Washington, along with other West Coast states, often set precedents for environmental regulation. If DOE’s reinterpretation spreads, contractors nationwide could face:
Reduced access to disposal sites
Increased excavation risk
Higher damage rates
This is why NUCA National, ACTS, and numerous local organizations have supported the Motion to Stay filed on behalf of Looker Properties.
Current Status
On June 12, 2026, the Washington State Attorney General’s office representing DOE granted the Stay and agreed to exercise enforcement discretion. This is a positive development, but not a resolution.
In June 2027, stakeholders will have the opportunity to provide testimony for or against the inclusion of hydro‑excavation slurry in the SGGP.