The Edmonds Marsh Watershed is tidally influenced and consists of a variety of soils. The FEMA flood risk map for the watershed area is shown below with the watershed outlined in blue and the 1% annual flood risk shown in purple. No part of the watershed is classified as regulatory floodway, and flooding is confined to the marsh area. This matches historical maps of where the marsh once existed, but today about half of the 1% annual flood risk area is developed land, with the remainder consisting of the marsh. For more information on this, check out my post on flooding and the Edmonds Marsh Watershed here.
Soils in this watershed are predominantly from glacial parent material, along with some from lacustrine–or ancient lake–deposits, and some from herbaceous organic matter within the Edmonds Marsh. The following map and key provide an overview of the soils found in this watershed.
Key
2 - Alderwood gravelly sandy loam, 8 to 15 percent slopes. Parent material: Glacial drift over glaciomarine deposits.
3 - Alderwood gravelly sandy loam, 15 to 30 percent slopes. Parent material: Glacial drift over glaciomarine deposits.
4 - Alderwood-Everett gravelly sandy loams, 25 to 70 percent slopes. Parent material: Basal till and glacial outwash.
5 - Alderwood-Urban land complex, 2 to 8 percent slopes. Parent material: Basal till.
6 - Alderwood-Urban land complex, 8 to 15 percent slopes. Parent material: Basal till.
17 - Everett very gravelly sandy loam, 0 to 8 percent slopes. Parent material: Sandy and gravelly glacial outwash.
19 - Everett very gravelly sandy loam, 15 to 30 percent slopes. Parent material: Sandy and gravelly glacial outwash.
27 - Kitsap silt loam, 0 to 8 percent slopes. Parent material: Lacustrine deposits.
28 - Kitsap silt loam, 8 to 25 percent slopes. Parent material: Lacustrine deposits.
34 - Mukilteo muck. Parent material: Herbaceous organic material.
78 - Urban land.
Soils 2, 3, 17, 19, 27, 28, and 34 are all classified as prime farmland, with the majority being classified as "Farmland of statewide importance". In this context, however, the area is fairly urbanized, encompassing part of the city's downtown and residential areas. Any parts of this watershed that are being farmed are done through backyard gardens. Given this is an established town and the acreage of the watershed is relatively small, it would make little sense to transition the use of this land. Some of the prime farmland soil is the marsh itself, which is a crucial habitat and should not be used for other purposes.
Given the map of the 1% annual flood risk and the fact that this almost perfectly mirrors the historical marsh's land, this area would be best converted back to marsh. The actual likelihood of this occurring is close to zero, but in my lifetime I have witnessed parts of this area flood numerous times, as is depicted in the flooding post linked previously, indicating that flooding is not currently being well-managed. Marshes act like sponges in times of flooding, as the soils and plants work to absorb the excess water. Nature had a perfect design for this land, and current urban land uses in this flood-prone area do not match this risk.
References
FEMA Flood Map Service Center | Search By Address. (n.d.). FEMA. Retrieved November 20, 2023, from https://msc.fema.gov/portal/search?AddressQuery=edmonds%2C%20wa
United States Department of Agriculture. (n.d.). Web Soil Survey. USDA Natural Resources Conservation Service; United States Department of Agriculture. https://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx