What Happened
- A critical leak was detected on the 48-inch transmission pipe from the river pumping station.
- This massive line serves as the primary water supply for the entire District.
- Immediate shutdown is required to prevent catastrophic flooding and property damage.
Why Immediate Shutdown Was Necessary
- Erosion Control: Uncontrolled high-pressure (180psi) water could quickly do major damage to surrounding area.
- Safety: Roads, buildings, other utilities could be damaged causing injuries or worse. Excavation crews cannot safely repair a pipe of this size while pressurized.
- Resource Protection: Structural failure of a 48-inch line compromises the long-term integrity of the system.
The Core Cause
- Compromised Pipeline: An external compromise to the protective coating on the 48-inch steel transmission pipeline caused damage and corrosion of the raw steel.
- Rapid Corrosion: The lack of protective lining exposed the pipe to rapid, localized corrosion, weakening the structural section of the mainline until it could no longer hold standard system pressure.
Why the Repairs Required Time
- Water Drainage: Crews had to safely drain nearly 1 million gallons of water—the entire volume held within 10,000 feet of 48-inch steel pipe.
- Extended Drainage Timeline: Due to the sheer volume of water and the need to prevent localized neighborhood flooding, draining this massive line required controlled discharging before the repair could begin. This was a slow process that took time.
- Critical Liner Curing: Once the structural patch was welded into place, a new specialized interior liner coating had to be applied. This coating required an absolute, uninterrupted curing timeline to dry before water could safely be reintroduced without washing the seal away.
- Slow Re-Pressurization: Refilling a 48-inch mainline must be executed at a slow, calculated pace to prevent high-velocity air pockets from fracturing residential connections downstream.
Post-Restoration Actions
- The District is investigating the cause of the damage to the outside of the pipeline. We are currently waiting for the report from our engineers on the failure, cause and inspection. When there is more information available and we have had time to conduct that investigation into how the line was damaged, that will be shared.
- The District has been in the process of rehabilitating and protecting the pipeline for the future for many years and there is still a lot to be done to complete that project
