Permanent Disinfection Boosting Systems at La Granada (CI 5771) and Lang Ranch (CI 5791) Reservoirs

To improve the enhanced wildfire resiliency of City's vital infrastructures, City will be installing permanent disinfection boosting systems at its water reservoirs.

The proposed improvements at the La Granada and Lang Ranch reservoirs (Attachment A) will include all civil, structural, mechanical, electrical, and finishing work necessary to complete the installation and commissioning of two (2) permanent chemical disinfection boosting systems.

The work includes, but is not limited to, procurement and installation of the disinfection boosting systems, chemical piping, chemical storage and containment systems, canopy structures, and all appurtenant improvements required for a fully operational system at each project site. The project also includes removal and relocation of existing equipment as required.

The installation of a permanent disinfection boosting system at La Granda and Lang Ranch Reservoirs will ensure that water disinfection levels can be maintained in these reservoirs to provide a high level of water quality to City’s residents and businesses.

The City’s Public Works Department manages the City’s water storage and distribution facilities consisting of 11 Calleguas turnouts (connections to the Calleguas Municipal Water District supply), four hydropneumatic pump stations, 16 pump stations, 16 reservoirs, and two boosting stations. Many of these sites need improvements to address enhanced wildfire resiliency, site drainage, accidental tank overflow containment, pump and electrical equipment enclosures, fencing, and the addition of emergency generators and disinfection boosting stations.

In December 2023 a comprehensive Citywide Water Storage Optimization Study was concluded, addressing water quality improvements within the City's water distribution network due to reduced demand and longer water age in the reservoirs after the 2022 drought. The study identified La Granda and Lang Ranch Reservoirs as high-priority sites for the installation of a permanent disinfection boosting system to assist with water quality.