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Newsletter – January 2019

Immediate Action Projects Phase 2 Begins at the Wastewater Treatment Plant

Photo of wastewater treatment plant.The second phase of work on the Immediate Action Projects related to the Clean Water Program’s wastewater treatment plant upgrades is beginning. A $6.3 million contract for the second phase of the Immediate Action Project, or IAP2, was awarded to Myers & Sons Construction LLC on January 7 upon City Council approval. The IAP2 construction package includes five separate projects that are needed to add backup protection to vulnerable points in the digestion and dewatering and solids handling processes, and to repair effluent piping.

Additional overflow and suction piping, and a third foam suppression pump, will be added to the digesters and digester piping. This additional equipment in the digestion process area will provide the backup and flexibility that the system requires. A third centrifuge system will be added to the dewatering process, which will provide adequate backup to the current centrifuge system.  One large cake pump, which is located in the solids building and transports cake (i.e., dewatered biosolids) to a storage hopper, will be replaced by two smaller cake pumping systems. This improvement will provide appropriately sized pumps and backup to that system. An additional cake hopper that will store all the dewatered biosolids until they can be hauled away will be added immediately outside the solids building. It will include a slide gate, access walkway, and platform. This additional hopper will provide more onsite storage, time between truck trips to dispose of the cake, and resources for operations to maintain other tanks in the digestion process. Lastly, repairs will be made to underground effluent piping and pipe connections.

The project will take approximately 20 months and is expected to be complete in late 2020.

To Flush or Not to Flush – Unused Medicines

Almost everyone has unused or expired prescription and over-the-counter medicines their house. Until recently, the usual way of getting rid of them was to flush them down the toilet. But, wastewater treatment plants are not designed to filter pharmaceuticals and hormones out of the water, and recent studies have shown that this creates a water quality issue that may negatively affect human health and ecosystems like the San Francisco Bay.

The best way to dispose of unused or expired medications is to look for a medicine take-back option. The U. S. Drug Enforcement Administration hosts periodic nationwide National Prescription Drug Take-Back events, which provide a safe, convenient, and responsible way to get rid of old medications. There are also permanent, approved medicine disposal sites across San Mateo County. You can find the closest location by visiting the  San Mateo County Health Website.

If a take-back location is not readily available, another acceptable disposal method involves mixing whole capsules and tablets with dirt, cat litter, or used coffee grounds, placing the mixture in a sealed plastic bag, and throwing it away in the trash. 

The Food and Drug Administration maintains a short list of medicines they recommend flushing due to the risk they present if accidentally taken; that list can be found at the  FDA Website. Always check the disposal instructions on all prescription medicines and dispose of accordingly.