Pasadena Water and Power Water Infrastructure Improvements

PASADENA, Calif.- Everyday, Pasadena Water and Power (PWP) works to improve local water infrastructure. PWP recently completed important water system infrastructure projects, and has new projects underway to ensure continued reliable, high-quality water.

Allen Reservoir Returned to Full Service after Eaton Fire Damage

The Allen Reservoir, which sustained damage during the Eaton Fire, was recently restored to full functionality. PWP operates 14 reservoirs across its water service area and is the largest water provider in Altadena. Allen Reservoir is a 4.1-million-gallon, concrete-lined, partially buried storage facility, located in Altadena and originally constructed in the 1930s. PWP worked diligently to keep half the reservoir in operation during the restoration work, allowing for continued water service. Repairs included replacing structural members, and rebuilding portions of the interior catwalk and handrail to restore the facility to full service. Upgrades at the facility also included replacing aged drain valves. After construction, the reservoir was thoroughly cleaned, disinfected, and returned to full service in April 2026.

Recently Completed Water Main Replacement Projects

PWP completed several major water main replacement projects in 2026, strengthening local system reliability. Maintaining and upgrading water mains is essential to ensuring reliable, high-quality service across PWP's 26-square-mile service area, which provides water to more than 165,000 residents and includes more than 535 miles of water mains.

"Continued investment in our water infrastructure is important to reliable, high-quality water service, and we appreciate the community's patience and partnership during the construction work," said David Reyes, Pasadena Water and Power General Manager.

After a year of construction, PWP completed water main replacements and related street improvements on Fair Oaks Avenue between Washington Boulevard and Montana Street. Crews replaced two aging mains, an 8-inch and a 12-inch line that had been in service for more than 90 years, with a new 12-inch ductile iron main. Trench repair, full-width pavement resurfacing, curb and gutter repairs, curb ramp upgrades, and updated roadway striping were completed in partnership with the City's Department of Public Works.

PWP also replaced a 100-year-old water main on Oak Knoll Avenue between Colorado Boulevard and California Boulevard. Completed in April 2026, PWP installed nearly 3,800 feet of new 8-inch ductile iron pipe to reinforce local service reliability. As part of larger ongoing improvements in the area, PWP also installed a new 12-inch water main on Holly Street between Marengo Avenue and North Arroyo Parkway, completed in May 2026.

Additional improvements were completed on Villa Street, where crews replaced a 6-inch cast iron main dating back more than 90 years with a new 8-inch ductile iron line despite the challenges of working on a narrow, high-traffic street. On Grand Avenue between California Boulevard and Green Street, a 90-year-old, 4-to 6-inch main was upgraded to a 12-to-8-inch ductile iron pipe, with work completed in March 2026.

Current and Upcoming Water Main Replacement Projects

PWP will continue with a full portfolio of water main replacement projects including Villa Street between Hill Avenue and Palo Verde Avenue, Colorado Boulevard between Patrician Way and Melrose Avenue, and Wallis Street between Marengo Avenue and Los Robles Avenue. For more information about these and other projects, visit PWPweb.com/Construction.