![]() ![]() Sodium bisulfite is added following the treatment to neutralize the chlorine to protect fish and sea life. Disinfectionįollowing secondary treatment, wastewater spends an hour in the chlorine contact chamber where chlorine is added to kill any remaining disease-causing organisms. The treated wastewater then goes to the disinfection process. At this point, the water is nearly 95% pure. Some are removed and incinerated and other organisms are returned to the aeration basins to begin the process again. ![]() The water then flows into large clarifiers where the organisms can settle to the bottom. Here, activated sludge is mixed with the wastewater and pure oxygen is added to create a perfect environment for the microorganisms to trap and remove contaminants. The wastewater flows into large, enclosed aeration basins. ![]() Secondary treatment uses micro-organisms (activated sludge) to remove pollutants from the wastewater. While there, the suspended solids (primary sludge) settle to the bottom and oil and grease (scum) rise to the surface where they are skimmed off and sent to solids handling for disposal. The water remains in the primary clarifiers for approximately two hours. In primary treatment, the wastewater flows into large basins called primary clarifiers. The wastewater then goes to the primary treatment process. This material is diverted to an incinerator and burned. From there, the water enters the grit chamber where it slows down to allow sand and other heavy particles to settle out. It then flows through coarse screening bars where rags and other large debris are removed. The wastewater is pre-chlorinated and aerated to control bacteria and reduce odors. It also contains a receiving station for residential septic tank sludge which is generated countywide. Preliminary treatment conditions the wastewater by removing materials which can harm or plug plant processes. The video below provides an overview of how wastewater is cleaned and treated at the Post Point Resource Recovery Plant. The City’s Comprehensive Sewer Plan identified the need for additional wastewater treatment capacity at the Post Point Plant. A Facilities Planning process began in late 2009, aiming to complete the plan in 2011. ![]() In 1993, Post Point was upgraded to include secondary treatment at a cost of $55 million. This upgrade to secondary treatment increased contamination removal to 95% before releasing it into Bellingham Bay. The Post Point Resource Recovery Plant began providing primary treatment for up to a peak flow of 55 million gallons per day (mgd) for the areas served by sewer. In addition, the City’s wastewater flows into the plant from over 250 miles of sewer collection mains located in Bellingham and the surrounding community. Septic tank waste is also collected from private homes throughout Whatcom County and brought to the plant for treatment. In 1974, Bellingham replaced the Whatcom Creek treatment plant with the Post Point Resource Recovery Plant at 200 McKenzie Avenue. The City first provided primary wastewater treatment in 1947, discharging effluent into a shallow part of Bellingham Bay, from a treatment plant located near the mouth of Whatcom Creek. Original storm water connections into sewers have since been disconnected. The ones carrying sewage have been intercepted ahead of their discharge points, and flows are now pumped to the wastewater treatment plant. Most of these early sewers are still in use. Starting in 1908, probably because of sewer overloads, some storm sewers were installed in developed areas of the city. Consisting of heat-hardened clay pipe, the sewers collected both sewage and rainwater and discharged into Whatcom Creek and Bellingham Bay. Sewers were first installed in 1892 throughout the developed areas of Bellingham. ![]()
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