07 - Laserfiche WebLink

of the discharge piping, which included surveying the discharge elevations of the underdrain system and the invert elevation of the sanitary sewer piping connection point, it was determined that the difference in elevations was less than expected. This caused concern that the need to pump would be much more frequent than anticipated, requiring significant staff time, and also caused concern that sewage could back up into the underdrain system discharge piping if an issue with the sewer system caused it to surcharge. To address these concerns, it is recommended that a small, pre-packaged pump station be installed as part of the project. While the small pump station would require permanent electrical power to operate, it will be automated, reducing the staff time needed to periodically pump out the system. The station would have a float control and avoid using the underdrain system for storage. It would also allow the underdrain system discharge piping to connect to the sanitary sewer pipe at an elevation above the sewer flow line elevation, thereby reducing the potential for backup. Also during design, the storm drains outfalls along Val Vista Park were inspected again. The re-inspection included the use of propelled video camera to determine the condition of the piping upstream of the outfalls. As a result, two more outfalls were found to need repairs in addition to the two repairs already identified. As discussed, the system currently being designed will divert recycled water collected in the underdrain system to the sanitary sewer. It should be noted that the system design will include valving that allows the underdrain system to discharge to the storm drain outfalls during the wet weather season when irrigation is not necessary. This design will meet the State Water Board requirement that recycled water not be discharged to the waterway. It will also, importantly, not divert wet season stormwater run-off to the sanitary sewer system for treatment at the DSRSD treatment plant. DISCUSSION To incorporate the pre-packaged pump station into the design, including the electrical service necessary for the pump station, as well the repairs required at the two additional outfalls, it is necessary to amend the existing agreement with Pakpour. On June 1, 2021, City Council approved a staff recommendation to enter into an on-call professional services agreement with Pakpour Consulting Group. The recommendation included authorizing the Director of Engineering to approve individual task authorizations up to $100,000 each. The recommendation also stated that if an individual task authorization was greater than $100,000, the task authorization approval would be presented to City Council for consideration. The task authorization to Pakpour for the design of the project subsequently approved by the Director of Engineering (on July 14, 2021) was for the not-to-exceed amount of $74,480. Since the recommended amendment is for the not-to-exceed amount of $36,915, the proposed total agreement will increase to $111,395, above the Director of Engineering's authority to approve. Therefore, staff recommends City Council authorize the City Manager to execute the amendment to the task authorization under the on-call agreement with Pakpour Consulting Group for the not-to-exceed amount of$36,915. Budget The current Capital Improvement Program budget includes $1 .6 million to fund the design and construction of the Val Vista Underdrain Improvements Project, CIP No. Page 3 of 4