The length of Prospect Street between Adams and Clay Streets is serviced by a 4-inch line installed in 1865. There have been no improvements since its original installation. The functional diameter of the main has been significantly reduced due to calcification, similar to other older street line sections in this part of the City. Fire flows on this stretch of Prospect Street range from 168 to 336 gpm, significantly less than the 1,000 gpm considered optimal for fire-fighting. Further, the residual psi measures at zero, as opposed to the required 20 psi.
The 612-foot line would be replaced with a 6-inch pipe that would restore both adequate fire flows and residual psi, and the main would be realigned. Finally, all residential laterals will be reconfigured to allow supply to the realigned main.
Current Status (September 2016)
The Prospect Street project was completed in July 2015.
The design and engineering for Prospect Street was completed in January 2015. Bids were released in mid-February. The contract was awarded in April 2015 to CME Services.
Final Notice to Proceed (NOP) was issued in April 2015 with construction beginning on April 24 and fully completed on July 24, 2015. All ‘as built’ drawings and specification were completed in November 2014, as was the post-project demobilization inspection. The project came in on time and under budget.
Preliminary post-project monitoring has been completed and shows significant increases in both pressure and flow (an increase in flow volumes from 336 to 1,000 gpm and an increase in pressure from 20+/- to 60-70 psi). Final monitoring will be completed in December 2015.
City of Nevada City
Catrina Olson, Assistant City Manager, (530) 265-2496 x134, firstname.lastname@example.org
Measurable Physical Benefits
Water Supply , Water Quality