Mountlake Terrace’s City Council adopted an updated Engineering Development Manual (EDM) and related municipal code amendments on March 5 after a staff presentation and public hearing that produced no testimony.
Lucas Cropp, Civil Engineer II for the city, outlined the principal changes in the 2026 EDM, including defining accessory dwelling units as 0.5 of an equivalent residential unit for stormwater billing and capital facility charges; adding a common-sense permit exemption for up to 2,000 square feet of ground disturbance or 50 cubic yards of material moved; clarifying overhead utility undergrounding obligations when an existing pole is 50 feet or less from a development; reducing the local access street curb-to-curb standard from 36 to 32 feet to encourage traffic calming; and revising minimum driveway-approach widths.
"One of the goals was to update our reference documents and reduce conflicting sections in the municipal code," Cropp said during his presentation. He told the council the changes are intended to align the code with the EDM and to reduce unnecessary permitting for low-impact work.
Council members asked specific questions about how the new overhead utility language would affect the downtown undergrounding program and about the traffic-calming rationale for narrower local streets. Cropp said the downtown’s 100-year vision to underground utilities remains unchanged and that the 50-foot metric is intended to clarify when trenching must continue to an existing pole rather than set a new pole.
Council member Doyle asked for more detail about the traffic-calming intent behind narrowing local-access streets. "By reducing that curb width, we can still maintain utility clearances but it doesn't need to feel like a thoroughfare," Cropp said, adding that a narrower pavement "will reduce the lane feel" and help slow vehicle speeds.
The council opened the public hearing on the EDM; no members of the public signed up to testify. Mayor Pro Tem Wahl moved to close the hearing and later moved the ordinance to adopt the EDM and associated code amendments. The motion was seconded and passed by voice vote with no member recorded in opposition; Council member Matsumoto Wright had been excused earlier in the meeting.
The approvals replace prior standards and direct staff to implement the EDM as the governing technical standard in lieu of conflicting municipal code sections.