Natural Resource Damage Assessment

Under state law (RCW 90.56.370), anyone responsible for spilling oil into state waters are liable for damages resulting from injuries to public resources.

The process for determining damages for an oil spill is called a Natural Resource Damage Assessment (NRDA). This process in Washington is defined in the “Oil Spill Natural Resource Damage Assessment” rule (WAC 173-183). The overall objective of this process is to restore natural resources to a pre-spill condition.

Following a spill, the responsible party (RP) is issued a letter inviting them to participate in a Preassessment Screening process where the state Resource Damage Assessment (RDA) Committee reviews the facts of the spill and determines the method used to assess damages.

Ecology is directed to lead the RDA Committee. Permanent members of the State RDA Committee include:

For each spill, if the RDA Committee must use the compensation schedule if they determine that:

  • Restoration of injured resources is not technically feasible.

  • Damages are not quantifiable at a reasonable cost.

  • The RP proposes a restoration project that is insufficient to provide adequate compensation.

Ecology began using the compensation schedule found in WAC 173-183 in 1992. It helps to determine a monetary value (damages) for injuries to public resources caused by the oil spill. The compensation schedule allows Ecology to collect damages based on a dollar per gallon charge. For spills less than 1,000 gallons this is $1to $100 per gallon range. For spills of 1,000 gallons or more this range is $3 to $300 per gallon spilled.

For more information on the NRDA process in Washington see "Focus on Assessing Oil Spill Damages."

The RP may be able to reduce the damages by acting quickly to contain and recover the spilled oil from the water. For more information see "Credit for Oil Recovery From ECY 050-49".

For more information on how oil impacts the environment see "Focus on Environmental Harm from Oil Spills - Impact of Oil on the Environment."

A spiller may be liable for more costs than just Natural Resource Damages. For more information see "Am I Liable for Other State Costs?"

Federal Natural Resource Damage Assessment

Large oil spills that cause great injuries to resources are also evaluated by federal trustee agencies and affected tribes. A trustee council is generally created and Ecology represents the state in that council. Other state agencies can be involved as well. For oil spills, federal agencies conduct NRDA under the authority of the Oil Pollution Act of 1990 (OPA 90). These agencies are usually the United States Fish and Wildlife Service or the National Oceanic and Atmospheric Administration.


effective 1/14/13

Chapter 173-183 WAC

Latest News

RDA Committee Meetings take place on the 2nd Wednesday of each month - contact Rebecca Post for more information.

Meeting Agenda
April 2014

Past Agendas & Meeting Reports

Washington State Restoration

Resource Damage Assessment by Account

Resource Damage Assessment by Date

Coastal Protection Fund

Map of Restoration Projects

Other NRDA Activities

West Coast Joint Assessment Team


Guidance: Credit for Oil Recovery
and Recovered Oil Data Form

Focus On: Assessing Oil Spill Damages

Focus On:
Environmental Harm from Oil Spills - Impact of Oil on the Environment

 Focus On:
Am I Liable for Other State Costs?