Natural Resource Damage Assessment

The Law: 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.

How it's done: 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 rule lays out a simplified process, called a Compensation Schedule, to calculate damages based on the habitat and organisms potentially impacted by the spill, the type of oil spilled, and the volume of oil spilled. 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.

RDA Committee: Ecology is directed to Chair the RDA Committee. Other permanent members of the state RDA Committee include: the Department of Fish and Wildlife, Department of Natural Resources, Department of Health, Department of Archaeology and Historic Preservation, and the State Parks and Recreation Commission. 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.

The Cost: Ecology began using the compensation schedule found in WAC 173-183 in 1992. It provides a simplified method 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 the range is $1 to $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."

Recovery Credit: 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?"

List of All Oil Spill RDAs: The following links are to lists of all Natural Resources Damage Assessments processed by the state to date. One list is sorted by the date of the spill and the other list is sorted by sub-region. To satisfy WAC 173-183-900, the lists provide the outcome of the preassessment screenings, the compensation schedule claims imposed, revenues to the Coastal Protection Fund (CPF), and the status of the claims. Here is a list of expenditures from the CPF.

Resource Damage Assessments sorted by date
Resource Damage Assessments sorted by sub-region

A map showing locations of projects funded through natural resource damage assessments is also available.

Where RDA Money Goes: Ecology deposits money collected from oil spill damage assessments into the Coastal Protection Fund (CPF). Most of the money is used to fund restoration of public natural resources. More about the Coastal Protection Fund and Restoration.

Other Washington state NRDAs

Federal NRDAs: 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.




Coastal Protection Fund & Restoration


RDA Committee

Meetings take place on the 2nd Wednesday of each month.


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?


Chapter 173-183 WAC

Contact Information

Dale Davis