← Well Drilling Guide
Cost by State

Well Drilling Cost in Washington State

Washington State is split by the Cascades into two very different worlds — wet western Washington with volcanic geology and dry eastern Washington with the Columbia Plateau basalt aquifer.

Average Total Cost
$9,000 – $20,000
Cost Per Foot
$25 – $65
Average Depth
100 – 500 ft
Regulator
Washington DOE
East vs West Washington
Western Washington (Seattle, Olympia, Bellingham areas): Glacial outwash and volcanic geology — 100–300 feet, very productive in Puget Sound lowlands, $28–$50/ft. Eastern Washington (Columbia Plateau basalt): 100–500 feet in fractured basalt, highly productive in some areas and problematic in others, $25–$55/ft. Mountain communities: 200–500 feet in hard volcanic rock, $40–$65/ft.
Washington DOE Requirements
Washington water wells regulated by DOE (Department of Ecology) under RCW 90.44. Licensed driller required. Well report required within 30 days. Water right permit required for use exceeding 5,000 gallons/day. Exempt domestic wells allowed for household, livestock, irrigation of 0.5 acres.
Common Questions
Washington residential wells typically cost $9,000–$20,000 installed. Western Washington Puget lowland wells are moderate in cost. Mountain and some eastern Washington areas run higher due to depth and hard rock.
Exempt domestic wells don't require a formal water right permit for uses under 5,000 gallons/day. However, a well permit from DOE is still required. Some areas of Washington have water-closed basins where new exempt wells are restricted.
Related Topics
Cost by State
Well Drilling Cost in Oregon
Cost by State
Well Drilling Cost in Idaho
Technical Reference
Average Water Well Depth by State
Important: Well drilling costs, depths, and regulations vary significantly within each state. This page provides general reference information only. Always get quotes from multiple licensed well contractors in your area and verify current state regulations before proceeding.