Tuesday, December 3, 2019

Updating fresh water rules to protect salmon spawning

Ecology is starting conversations about rule changes to help salmon recovery

many bright red blobs, which are salmon, in a clear river
Image by NOAA Fisheries
All across the state, people and organizations are asking what they can do to help salmon and orca. There are simple, every day actions we can all take to prevent water pollution, like limiting the amount of chemicals we use on our lawns, as they can be washed into streams and rivers. At Ecology, we are taking a wide variety of actions to better protect and restore these iconic species, including grants for community projects, reducing toxic chemicals from getting into our water, providing scientific support, and taking regulatory actions.

Salmon Spawning and Water Quality

Salmon play a critical role in our fresh and marine water ecosystems. Unfortunately, salmon populations have been declining in our state for more than a decade. In Washington, 15 distinct populations of salmon and steelhead are listed as either threatened or endangered, and according to the most recent State of Salmon report, eight of those populations are either getting worse or not showing signs of recovery.  

To support salmon recovery, we are considering making changes to the state’s fresh water standards. These changes could help improve the physical habitat and water quality for our rivers and streams to benefit all salmonids; including trout such as cutthroat, redband, bull, brown, rainbow, and brook. Specifically, we want to ensure salmon nests (called redds) have enough oxygen to support incubating eggs and newly hatched young. We also want to better protect these nests from the effects of too much fine sediment in the water.

“Salmon need a healthy environment to spawn and thrive. If we want more salmon in our rivers, we need to continue to help improve their environment,” said Heather Bartlett, Ecology’s Water Quality Program Manager. “The rule changes we are considering would help improve the spawning habitat for salmon across the state and compliment all of the great work being done to rebuild and protect salmon habitat.”


Bright orange eggs with small translucent fish sticking their heads out.
Larval salmon, called alevin, stay protected between the stream
gravel until they absorb their yolk sack and emerge as young fish.
Image by pnwsalmoncenter.org
Salmonid eggs incubate in the gravel of fresh water streams and need enough oxygen to properly grow into larvae and emerge from the gravel. In regulatory terms, we refer to the oxygen in the water as Dissolved Oxygen and have a water quality criteria for how much oxygen needs to be in the water for aquatic species to be healthy.

We are considering adding an additional measure to the existing criteria to help ensure habitat conditions in gravel are ideal for salmon spawning. We want to make sure our standards provide the necessary conditions for growth, survival, and reproduction. Improved standards would help us better identify waters throughout the state that have oxygen issues that could be affecting salmon spawning.

There are a number of reasons why a water body could have low dissolved oxygen, including warm water temperatures and excess nutrients.

Salmon eggs and larvae need oxygen to breathe. A line drawing of a fish in a river with a gravel bottom. Arrows showing water flows through gravel and carries oxygen to group of small red eggs (called a redd). Arrows showing dissolved oxygen moves between the water column and the gravel bed. Redds often have lower dissolved oxygen than the water column. line drawing showing eggs outlined between gravel and baby fish.

Fine Sediments

A pink salmon excavates a loose gravel area to create
a nest (called a redd). She lays her eggs in and covers them up.
We are also considering the addition of new water quality criteria to limit the impact of fine sediment on salmon spawning gravel beds. Currently, the Water Quality Standards provide protection for spawning habitat but do not specifically address fine sediments.

Fine sediments are an issue for salmon nests because sediments can settle on the nests and block the flow of water through the gravel, depriving eggs and larvae of the oxygen they need.

In addition, adding fine sediment criteria is consistent with our agreement in the 2018 U.S. District Court Stipulated Order of Dismissal between Northwest Environmental Advocates, EPA, and Ecology.  In the agreement, we committed to completing draft rule language by Oct. 18, 2021.

Fine sediment is the result of soil erosion, which can happen for a wide variety of reasons, including development or construction, agricultural practices, and forestry. There are generally best management practices in place for these industries and activities to mitigate erosion and sediment pollution.
Fine sediment is not suitable spawning habitat. Line drawing of fish in river with gravel bed. Shows fine sediment covering the redd. Fine sediment blocks the flow of water and oxygen.  Less oxygen reduces hatching success.

Next Steps

This is the development phase of the rule, which means we have not yet drafted a proposed rule. Over the next few months, we will meet with tribes, stakeholders, and government agencies about the potential rulemaking, to seek their ideas on solutions, alternative approaches, and concerns.

We plan to propose rule language for comment in fall 2020. At that time, we will host workshops and public hearings. After evaluating the feedback we receive, we will make decisions on changes to the water quality standards for dissolved oxygen and fine sediments in fresh water.

To learn more about the rulemaking, visit our rulemaking webpage.

By Stacy Galleher and Marla Koberstein

No comments: