Well 9 Hydrogen Sulfide (H2S) Filter Media Replacement ProjectCC-1837 November 18, 2025
Well 9 - Project Location
Warner Avenue
Project Background
H₂S detected in 2011 at Well 9, causing strong “rotten egg” odor and aesthetic water quality concerns.
Granular Activated Carbon (GAC) treatment facility built in 2018 to remove H₂S and ensure compliance with drinking water standards.
GAC media in service for 7–8 years, exceeding its 5-year life expectancy.
Declining media performance
requires daily backwashing,
increasing O&M costs and staff
time.
Project Benefits
Maintains odor-free, high-quality drinking water for residents.
Supports the Basin Production Percentage (BPP) by maintaining groundwater production capacity.
Reduces reliance on more expensive MWD imported water.
Improves operational efficiency
and extends facility life.
Funding
Construction Costs
Karbonous, Inc. Bid $527,375
10% Contingency $52,737
Supplemental Costs $44,888
TOTAL COST $625,000
Current Funding
Water Fund Budget $400,000
Water Master Plan Fund (Reallocation) $225,000
Note: CC-1734 (Wells 4, 7 & 13 On-Site Chlorine/Fluoride Project) will have adequate funds remaining to cover budget shortfall.
Tentative Construction Schedule: February–March 2026
Questions?