By Dave Edwards, PUC
This past March the Review carried a series of articles that provided a historical background of each of the City’s public utilities, and listed some of the immediate and long-term needs that must be addressed to keep them functioning properly. This missive is a report to the customer – owners of some of the summer projects undertaken by both our city crew and some specialty service providers.
Let’s begin with the utility with the fewest aesthetic qualities – the sanitary sewerage utility. The system has three basic components: the collection system, the lift station, and the sedimentation ponds.
This summer another dozen of the manholes that provide access to the sewer mains were repaired and resealed. The sewer mains, in addition to the normal “jetting” to keep them clear and open, were subjected to video inspections (these are recorded and filed), and in a few places a cutting tool was used to trim back some of the laterals extending into the mains. This effort removed potential blockages, and it provides a better outcome for future maintenance activities. Keep in mind that a good portion of the collection system is at the century mark.
The lift station pumps waste water from the collection system to the lagoons (sedimentation ponds). Basically it’s a catch basin with two pressure pumps and some control valves. The pump motors and impellars are pulled on a regular basis for maintenance and repairs. This summer, on an alternating schedule, the pumps – in their entirety – were removed for inspection and maintenance. The first was rebuilt and returned to service. The basin in the pedestal of the second pump was found damaged and had to be replaced. While working with the pumps the check valves that are a part of the system’s plumbing were also replaced. To provide a more dependable pump control system, a new set of float controls was installed. This part of the 55 year-old system has, essentially, been rebuilt.
The sedimentation ponds also received a 55 year inspection. Members of the city crew aboard the “titanic” ventured into the lagoon to perform a “sludge test” to see how much capacity has been lost due to sedimentation. It appears that only six inches of a seven foot design capacity have been lost. The ponds are in good shape and no one was lost at “sea”.
