PUBLIC UTILITIES ADVISORY BOARD AGENDA ITEM
ACTION REQUESTED:
title
Receive the Water Utility System Performance Metrics Report
body
DEPARTMENT: Water Utilities
SUBMITTED BY: Darrell Blenniss, Director of Water Utilities
BOARD/COMMISSION REVIEW:
N/A
BACKGROUND:
This memo provides a summary and analysis of our core metric dashboards. The data reflects our year-to-date (YTD) performance through August 2026 across safety, system reliability, water consumption, wastewater treatment, and distribution infrastructure.
Overall, the utility is performing well within our designed capacities, showing notable improvements in system reliability and pacing favorably in infrastructure leak reduction compared to the prior year.
DISCUSSION:
City Safety: Vehicle Incidents
Safety remains a top priority for our department. Year-to-date, the Department of Public Utilities - Water (DPU-W) has recorded 2 preventable vehicle incidents, mirroring our performance at this time last year (2 incidents).
● Incident Types: The incidents involved one backing collision and one rear-ended collision.
● Financial Impact: These resulted in $251 in vehicle damage and $5,634 in third-party damage.
● Trend & Action: While our overall incident count is very low (especially compared to other city departments like the NPD, which has 11 YTD), the nature of these incidents reinforces the need for our continued emphasis on routine defensive driving and situational awareness training for our operators.
System Reliability: SAIDI
The System Average Interruption Duration Index (SAIDI) measures the number of minutes the average customer can expect to be without water service during a 12-month period.
● Current Performance: As of July 2026, our 12-month average SAIDI is 5.14 minutes. This is an excellent 15.48% improvement (decrease) compared to the prior year's 6.08 minutes.
● Noteworthy Trend: Historically, our SAIDI had been trending steadily upward from a low of 1.40 in 2012 to a peak of 6.62 in 2021. The current drop to 5.14 indicates that our recent investments in preventative maintenance and rapid-response protocols are effectively reversing that decade-long trend.
● Interruptions: The total number of interruptions dropped 16% year-over-year (from 112 to 94).
● Note on Average Duration: The board may notice an anomalous 688% increase in "Average Duration" (1,364.8 minutes). This is a statistical outlier driven by a single, zero-customer impact event on May 4, 2026 (WO #323458), which remained open for 14,530 minutes. It does not reflect prolonged outages for our residents, as the average number of customers affected per interruption actually decreased by 9.2% to 11.9 customers.
Water Consumption and Capacity
Our water supply system remains highly resilient and well within capacity.
● YTD Usage: Total consumption through August 2026 is 3,273 Million Gallons (MG).
● August Snapshot: August usage was 456.74 MG, which is significantly lower than the historical average for August (597.44 MG).
● Capacity & Allocation: We are currently averaging 13.47 MG per day. This is roughly 20.7% below our DuPage Water Commission allocation of 16.998 MG per day. Furthermore, our system capacity is designed to handle up to 35.8 MG per day, ensuring we have abundant headroom for future growth or severe drought conditions.
● Trend: Looking at annual usage since 2008, overall city consumption continues a gradual, long-term downward trend, reflecting improved water conservation efforts by our residents and businesses, as well as more efficient plumbing standards.
Wastewater Treatment: Springbrook Effluent
The Springbrook Treatment Plant is operating efficiently and safely processing city wastewater.
● System Load: The plant's Design Max Flow is 55.13 MG.
● Recent Peaks: Effluent peaked at 46.82 MG on July 4, 2026 (85% of design maximum). This peak directly correlated with a heavy summer precipitation event (2.6 inches of rainfall).
● Trend: YTD, the plant has only experienced 2 "High Flow Days" (exceeding 80% capacity). During normal, dry-weather periods, effluent safely ranges between 15 and 25 MG per day (roughly 25% to 45% of total capacity).
Infrastructure: Distribution Leaks
Monitoring and repairing distribution leaks is vital to minimizing non-revenue water loss.
● YTD Leaks: We have confirmed 84 leaks through August 2026.
● Year-Over-Year Comparison: This is a notable improvement from 2025, where we had 104 leaks by this time of year, and puts us exactly on pace with our 2024 performance (84 leaks). February was our most challenging month (19 leaks), but numbers have dropped significantly through the summer (only 3 leaks in August).
● Causes: The vast majority of failures are attributed to Holes (40.7%) and Radial Cracks (20.9%).
● Financial Impact: These 84 leaks have resulted in an estimated 72.5 Million Gallons of water lost, carrying a calculated cost of $404,000 ($4,492 average cost per leak). While this cost is standard for a system of our size and age, continuing to invest in our leak survey and acoustic sensor programs (which successfully identified 25 of these leaks proactively) remains a high-ROI strategy for the utility.