Environmental Rules in Tigard, OR (2026)
4 verified environmental rules for Tigard, Oregon, sourced directly from the municipal code and official government pages.
Verified from official government sources
Stormwater Management
In the City of Tigard, Oregon, the Director and City Engineer issue a development permit only where adequate provisions for stormwater and floodwater runoff have been made. Storm drainage must be separate from the sanitary sewer, culverts must handle the entire upstream drainage area, and Clean Water Services rules are adopted as part of the city code.
Tigard Oregon Storm Drainage Requirements for Development
Some RestrictionsTigard Municipal Code § 18.910.100
§ 18.910.100. Storm Drainage. ... A. General provisions. ... The Director and City Engineer shall issue a development permit only where adequate provisions for stormwater and floodwater runoff have been made, and: 1. The storm water drainage system shall be separate and independent of any sanitary sewerage system; ... C. Accommodation of upstream drainage. A culvert or other drainage facility s...
Erosion Control
In the City of Tigard, Oregon, no one can drag, track or deposit mud, dirt, rock or debris on a public street or into the public storm and surface water system, and any deposit must be removed immediately. For work in the right-of-way, the city engineer can require an erosion control and pollution prevention plan before issuing an encroachment permit.
Erosion and Sediment Control in the City of Tigard, Oregon
Some RestrictionsTigard Municipal Code §§ 10.32.205, 15.16.050
No person shall drag, drop, track or otherwise place or deposit, or permit to be deposited, mud, dirt, rock or other such debris upon a public street or into any part of the public storm and surface water system. Any such deposit of material shall be immediately removed using hand labor or mechanical means. No material shall be washed or flushed into any part of the storm and surface water syst...
Flood Zones
In the City of Tigard, Oregon, a development permit is required before construction or development begins inside any area of special flood hazard, and it covers all structures, manufactured dwellings, fill and other development. The areas are mapped by the Flood Insurance Study for Washington County effective October 19, 2018. Violations are Class 1 civil infractions.
Floodplain Development Permits in Tigard, Oregon
Significant RestrictionsTigard Municipal Code § 9.10.040
I. Floodplain Development Permit Required. A development permit shall be obtained before construction or development begins within any area horizontally within the area of special flood hazard established in Section 9.10.030.B. The development permit shall be required for all structures, including manufactured dwellings, and for all other development, as defined in Section 9.10.020, including f...
Flood Elevation Requirements
In the City of Tigard, Oregon, new and substantially improved residential and nonresidential structures in riverine flood zones with base flood elevations must have the lowest floor, including basement, elevated at one foot above the base flood elevation. Nonresidential buildings can be floodproofed instead. Critical facilities must be three feet above base flood elevation.
Base Flood Elevation Requirements in Tigard, Oregon
Significant RestrictionsTigard Municipal Code § 9.10.050
When no base flood elevation data is available, the elevation requirement for development proposals within a riverine unnumbered A Zone is a minimum of two feet above the highest adjacent grade, to be reasonably safe from flooding. ... M. For Riverine (Non-Coastal) Areas of Special Flood Hazard with Base Flood Elevations. ... 2. Residential Construction. a. New construction, conversion to, and ...
Looking for Washington County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Tigard city rules.
Environmental Rules in Washington County →