Forestry pollution

How do forest practices protect the environment?

The goals of the Forest Practice rules are to:

• Provide compliance with the federal Endangered Species Act for aquatic and riparian-dependent species
• Restore and maintain stream habitat to support a harvestable supply of fish
• Meet the requirements of the Clean Water Act for water quality
• Keep the Washington timber industry economically viable

To meet water quality requirements, landowners follow forest practices rules and use best management practices to know how many trees to leave around streams and other water bodies. Streams subject to forest practices rules are generally categorized based on the type of shoreline, whether they have fish, and whether they flow year-round or go dry during a year of normal rainfall. These stream categories, along with any necessary site-specific protections (for example, steep slopes), all contribute to how many trees are left to protect stream and aquatic habitat. A core part of the adaptive management program is to conduct studies to test the effectiveness of the rules and best management practices, and if the rules are found to be ineffective, the program recommends adjustments to the rules to better meet program goals.  

There is a water temperature problem in non-fish streams

Streams that flow year-round and don’t have fish are called perennial non-fish-bearing, or Type Np streams. Current forest practices rules allow for trees to be harvested down to the edge of the stream for up to 50% along the length of the stream. Sensitive areas are also required to be buffered, which sometimes increases the overall percentage of stream buffered. However, under the current rules, there are often areas near these streams that do not have enough trees to provide shade to help prevent the water from warming up. Any one of these streams being a little warmer may not directly impact fish, since they are not present in these streams, but could affect other aquatic life. Also, when the streams flow together, they can collectively warm up downstream water that may have fish.

Science produced by the Forest Practices Adaptive Management Program shows that current Type Np buffer rules are not preventing streams from warming. In 2018, the Timber, Fish and Wildlife Policy Committee agreed that the science showed warming impacts and that the forest practices rules needed to be updated.

Forest Practices Board rulemaking 

In 2023, the Forest Practices Board voted to work on a new buffer rule that may help reduce warming of Type Np streams. The Board chose to consider a rule proposal which was submitted by a “Majority caucus” of the Policy Committee that consisted of Western Washington Tribes, Eastern Washington Tribes, Conservation caucus, WDFW, and Ecology.

The proposed buffer rule provides new best management practice options that reduces harvest next to all Type Np streams in western Washington. This will create an expanded buffer of trees around the stream. The widths of the buffer vary from 50 to 75 feet, depending on conditions.

On June 6, 2025, the Forest Practices Board will vote on whether the proposed buffer rule should move forward to a formal public review period.

Our role in the Board’s rulemaking

Under the Forest and Fish agreement, Ecology has the responsibility to determine whether the Board’s proposed rule will meet water pollution control laws. To do this, we conducted an analysis (called a Tier II Analysis) of the proposed rule to determine if the rule is likely to cause:

• Warming of water that is currently higher quality (such as colder water)
• If warming will occur, whether it is necessary and in the public interest to allow it

This means that if the proposed buffer rule will still cause some increases in water temperature, we need to determine if the benefits of the rule meet or exceed the costs. We use the best available current scientific data for this analysis.  

While our analysis is not part of the Board’s formal rulemaking materials, we will be holding our public comment at the same time as the Board’s proposed rule (CR102) public review period.

We presented our preliminary findings to the Forest Practices Board on May 14, 2025. Our draft analysis found that the proposed rule would substantially improve water quality. The proposed buffer options should result in minimal stream warming and the warming that may occur is likely to be shorter when compared to the current rule. We agree with the cost benefit analysis commissioned by the Board which found that the probable benefits of the proposed rule are likely to outweigh the probable costs. And finally, we note that further Adaptive Management Program research is necessary, some of which is already underway.

If the Board votes to move forward with the proposed buffer rule and formal public review period, we will formally announce our separate public comment period and link to our draft Tier II Analysis report on this webpage. 

Other ways we help

In addition to our role on the Forest Practice Board and  the two Adaptive Management committees, we also:

• Assist with DNR’s Forest Practices Compliance Monitoring Program that evaluates whether timber harvest and forest road construction are in compliance with the Forest Practices Rules. The program publishes a statistical study of post-harvest evaluations every two years and reports results directly to the public and the Forest Practices Board.
• Have field inspectors who provide technical assistance to forest landowners and other agencies to help ensure the forest practices rules are followed. Contact your local regional office for more information or questions.