Establishing New Moorings in Zone 6 of the Columbia River to Monitor Key Salmon Habitat

This project will allow CRITFC’s Coastal Margin Observation and Prediction (CMOP) program to develop, deploy, and maintain two new moorings for real-time monitoring of salmon habitat within Zone 6 of the Columbia River. Migrating salmon are vulnerable to unfavorable river conditions, such as high temperatures and low dissolved oxygen levels, and real-time data in these locations can provide a powerful new tool for tribal fisheries managers. Understanding environmental variability and change in salmon habitat contributes to protecting salmon throughout their lifecycle, which is a critical component of the Columbia River Anadromous Fish Restoration Plan of the Nez Perce, Umatilla, Warm Springs, and Yakama Tribes (https://plan.critfc.org).



Currently, CMOP operates a network of real-time biogeochemical stations and buoys in the Columbia River estuary and coastal ocean that provide continuous data on conditions affecting salmon habitat and survival. However, no comparable observing capability exists in the upriver Zone 6 reach, where water quality dynamics affect the suitability of habitat for migratory salmon and steelhead. Water temperatures in Zone 6 become dangerously warm during the summer. Cold water refuges at tributary deltas provide critical habitat for ESA-listed salmon and steelhead populations, but cold water at tributary deltas can be degraded by local backwaters (warm pools) or by shallow deltas. This project will fill a data gap by extending the CMOP observatory into these key river habitats.



CRITFC’s CMOP team will design, build, deploy, and maintain two fixed-location moorings in Zone 6. Locations will be at tributary deltas such as the Klickitat, Wind, or Deschutes rivers, or at known warm pools. The exact location of moorings will be determined after consultation with commissioners and natural resource managers from the CRITFC member tribes.

• Mooring 1 will be equipped with multiple sensors to monitor bottom-water conditions (e.g., dissolved oxygen, temperature, turbidity) and additional temperature sensors at mid-water and surface depths.

• Mooring 2 will focus on vertical temperature structure, with sensors at three depths to capture thermal gradients relevant to salmon migration and refuge use.



Both moorings will collect data at sub-hourly intervals and transmit observations via telemetry for real-time access. The moorings will be designed for seasonal deployments (spring–fall). All data will be archived and made publicly available through the CMOP website, where they will undergo standardized quality control and documentation.



Through other funding sources, the CMOP field program has developed extensive expertise in designing, constructing, deploying, and maintaining instrumented buoys and moorings in estuarine and coastal environments, as well as in managing the associated instrumentation, telemetry systems, and data pipelines. The program has dedicated vessels, QA/QC protocols, and data management infrastructure that will directly support this project. The new PCSRF project funds will be used to:

• Conduct a needs assessment to determine exact mooring locations and instrumentation (Year 1)

• Purchase equipment and design moorings (Year 1)

• Obtain necessary permits (Year 1)

• Build and deploy moorings (Year 2)

• Service moorings and recover during offseason (Years 2-4)

• QC and deliver data to CMOP website (Years 2-4)

• Conduct outreach with tribal fisheries managers to spread awareness of these data and assess their utility (Years 2-4)



This project will generate new real-time, high-resolution time series of water quality data in Zone 6, providing insight into how temperature, oxygen, and other conditions vary across space and time in salmon-relevant habitats. These data will support decision-making and restoration prioritization by fisheries mana

The survival of Pacific salmon depends on maintaining suitable habitat conditions during migration. Migrating salmon are particularly vulnerable to warm water (Keefer et al. 2018) and to low concentrations of dissolved oxygen (hypoxia) (Roegner et al. 2011). High water temperatures can be especially problematic in tributary deltas, where cold water refuges can provide critical cool-water habitat that can increase the survival rates of migrating salmon (Goniea et al. 2006). Despite the recognized importance of these environmental conditions for salmon survival and for fisheries management strategies (e.g., construction of new cold water refuges), few programs collect continuous, real-time biogeochemical data from key salmon habitat within Zone 6 of the Columbia River.



This project will establish and maintain two new instrumented moorings at strategically selected locations to monitor water quality relevant to salmon survival. Sensors on these moorings will collect high-frequency data on temperature, dissolved oxygen, and other key water quality parameters. Data will be transmitted via telemetry and made publicly available on the CMOP website in near real-time, allowing tribal fisheries managers to monitor environmental conditions as they occur.



Outcomes from this project include providing actionable, real-time information to support tribal decision-making, including assessing habitat suitability, planning habitat restoration, and prioritizing management actions for ESA-listed salmon populations. By filling critical monitoring gaps in Zone 6, these moorings will strengthen tribal capacity to safeguard migrating salmon and improve survival in key river reaches, providing a powerful new tool for salmon conservation and adaptive management.