Meadowdale Beach Monitoring

Restoration Monitoring

Snohomish County Surface Water Management (SWM) is coordinating with multiple partners to monitoring the effectiveness of the Meadowdale Beach and Estuary Restoration Project. Restoration monitoring partners include Tulalip Tribes, Snohomish County Marine Resources Committee, Edmonds Stream Team, Blue Coast Engineering, U.S. Geologic Survey, and Washington Sea Grant. The monitoring will inform how the restored estuary is adjusting over time to stream and coastal processes, as well as which fish species are using the restored habitats. The estuary, beach, and surrounding vegetation are expected to adjust over time and there is much to be learned from how and where changes occur. As this is the first stream mouth restoration project along the Puget Sound shoreline impacted by the BNSF railroad, effectiveness monitoring is particularly important to inform the design of future restoration projects at other stream mouths. In addition, the effectiveness monitoring provides essential information to document the benefits and sustainability of investments by Snohomish County, the grant funding programs who contributed to the restoration, and to BNSF who controls the right-of-way.

To guide the monitoring, SWM prepared a comprehensive Monitoring Plan. To support the development of the Monitoring Plan, SWM convened a Meadowdale Monitoring Group consisting of scientists and engineers interested in collecting data at Meadowdale Beach Park to evaluate the post-restoration conditions. Environmental Science Associates (ESA) was hired by SWM to prepare the Monitoring Plan and support effectiveness monitoring in post-construction years 1 through 4.

The Monitoring Plan identifies 17 monitoring elements to characterize the biological, physical, and chemical outcomes of the restoration project. The Monitoring Plan focuses on monitoring activities in the first ten years following restoration. Monitoring beyond ten years may continue depending on the findings of the initial ten years and the availability of monitoring funding. Five of the monitoring elements are required as part of the grant funding agreements. These five monitoring elements will be completed by DCNR. The five required monitoring elements focus on fish passage conditions, estuary elevations relative to tidal water levels, stream habitat conditions, large woody debris retention and recruitment, and the survival of planted vegetation.

The Monitoring Plan includes eight additional monitoring elements focused on sediment transport and deposition in the restored estuary and adjacent nearshore, fish use, fish prey production, and additional vegetation performance. Pending the availability of funding, the additional monitoring is planned to be led by SWM, the Tulalip Tribes, or the Edmonds Stream Team (volunteers). Funding for the additional monitoring is being sought. Tulalip Tribes has committed funding from a National Estuary Program grant. The Tulalip Tribes and SWM obtained additional monitoring funding from WDFW’s Estuary and Salmon Restoration Program. The Edmonds Stream Team uses student volunteers to conduct salmon spawning ground surveys.

The remaining four monitoring elements are currently not planned for implementation because neither a monitoring lead nor funding has been identified. These additional monitoring elements are extended spawning ground surveys, carbon sequestration, wildlife use, and public use.

The Monitoring Plan identifies the lead organization, data collection methods, and sampling schedule for each monitoring element. Year 1 post-construction monitoring was completed in 2023 based on the completion of railroad bridge and estuary restoration construction in 2022. The monitoring elements completed in year 1 were:

• fish passage conditions
• estuary channel elevations survey
• stream habitat conditions
• large wood retention and recruitment
• planted vegetation survival and coverage
• additional vegetation characterization
• sediment transport and deposition in upper estuary upstream of railroad crossing and creek outlet
• sediment transport and deposition in lower estuary downstream of railroad crossing and adjacent nearshore
• fish use
• salmon spawning ground surveys
• forage fish egg samples
• macroinvertebrate production in estuary
• photo points