At the Lynden wastewater treatment plant, we create biosolids and Biolyn, a Class A compost product using biosolids and leaves from street sweepings, chipped wood from parks, and other wood sources.
In April, a few of the Northwest Biosolids members were able to stop by the Lynden wastewater treatment plant, en route to a committee meeting.
The City of Lynden has a compost facility, where they compost ground branches and leaves, sawdust, and biosolids to make a Class A compost that is available for both commercial landscapers and the public, called Biolyn compost. A finely screened compost is sold to their customers, and the course version is available for the public to pick up.
At Lynden they have a very clean, organized, well managed compost facility. Citizens and the Parks Department brings trees and leaves to be ground into woody debris, which provides the compost operations with a great bulking agent and helps out the local citizens. We grind and mix their materials, then compost using aerated (both negative and positive) static piles in a covered bays that are connected to a biofilter for odor control. We monitor the conditions of their piles using ECS’s Comptroller system. The first four bays are used for the first stage of composting, then turned and placed in bays five through eight to finish composting. Once the pesky pathogens have been removed and the piles start to cool down, which takes about 21 days, the compost goes into the curing shed for about 30 days to meet stability requirements. Inside the curing area, which is covered, there is also room for storage. The finished product is screened and placed in piles in the parking lot for pick up.
The rest of Lynden’s biosolids go to Boulder Park and other similar applications, where they are used to build the soil and grow healthy wheat, canola, and sunflowers.
Water and wastewater staff manage the wastewater plant and pump station facilities that collect and transport sewage from homes, businesses and industries. They manage the wastewater through a complex process where the solid remains are used to make compost and the water remains are treated and discharged back into the Nooksack River – clean and ready to be utilized by fish, other aquatic species and county residents downstream.
The wastewater treatment plant was built in 1975 and the compost facility was built in 1996. The wastewater treatment plant has an average annual flow of 1.2 MGD, and produces 600 dry tons of biosolids per year and about 4000 cubic yards of compost. About 70 tons were used to make the compost. Lynden sells compost to local nurseries, contractors, landscapers, and the Lynden Parks Department and Cemetery District.