Welcome to the City of Lompoc

Wastewater Division

Wastewater Plant Update

Posted: April 4, 2008

Update March 2008: (Click on thumbnails to view pictures larger)

The excavation for the new Influent Pumping Station got progressively deeper through March.

The contractor was approaching the final depth of 40 feet below grade. This excavation will allow for the construction of a four-pump influent pumping station which will take the sewage received by the plant and send it on to the downstream treatment processes. During digging near the existing Influent Pump Station building, another buried surprise was uncovered: an old abandoned reinforced concrete pipe which had to be demolished and removed.

With the exterior and interior walls of the new Oxidation Ditches well completed, the contractor began work to install walkways which will run perpendicular to the length of the tanks and will allow access by Operations and Maintenance staff when the tanks are in operation. The structures for the fabrication of the concrete walkways are supported by scaffolding in the tanks which will be removed after installation of the walkways.

The water leaving the Oxidation Ditches will pass through a flow distribution structure and be split evenly between three new Secondary Clarifiers as clarifier influent. The three large pipes delivering this influent were installed.

Toward the end of March, the internal mechanical structures for the new secondaries began to arrive by truck. These structures will be coated and prepared for installation in the tanks.

Biological solids from the secondary treatment (Oxidation Ditch) system will be removed and sent to Dissolved Air Floatation Thickeners to prepare for final treatment. The external structures for these Thickeners were completed and the contractor moved on to installing the piping and support structures for the Thickener pumps and other equipment.

Many activities occurred at the Filter/UV building; this treatment unit will filter the water through three cloth media filters before it enters the two, long Ultraviolet (UV) channels for disinfection. The slab to receive the filters was poured while the structures of the UV channels were completed.

Within the Filter/UV building is an electrical room which will contain all the electrical connections and process control equipment for the treatment unit. Installation of the underslab conduit was completed and covered with a concrete slurry to prepare for a final slab pour.

Throughout the work site, more electrical work was progressing. The walls for the new Electrical Building located near the new Oxidation Ditches were poured in preparation for receiving the new MCC's (motor control centers). New MCC's were also installed in the existing Influent Pump Station and Blower Building.

Behind the Blower Building, excavation started for the installation of the new 1250 KW diesel engine generator. This equipment will power the entire facility in the event of an electrical power failure to ensure the facility will continue to treat the water coming into the plant.

Finally, the slab for the new Hot Water Boiler facility was constructed . These new boilers will supply hot water to maintain the temperature of the anaerobic digesters at the required level of 95-97 degrees F.

Check back again in May to see what happened in April.