Snowmelt I/I, a Tripped Pump, and a Discharge to the Creek

1. Protect public health and stop the exposure. Barricade and sign the discharge area; keep people and pets out of the creek and the gutter line. Public contact with raw sewage is the highest-consequence risk in the whole event and the cheapest to control.

2. Restore pumping. Get the tripped pump back on line - reset the overload, check for a jammed impeller or a rag-bound pump, and check the run/start capacitors and controls. If it will not run, rent or borrow a portable pump and set it as a temporary bypass. Every minute the wet well stays at high-high, more manholes surcharge.

3. Contain the overflow at the manholes. Sandbag or dam the gutter so the flow is captured rather than reaching the storm drain, and begin vacuuming the surcharge points to keep the volume down.

4. Address the basement calls. Dispatch someone to assess; document whether the backup is from the public main (system responsibility) or from a private service or yard drain. Either way, respond and record what you find - the documentation matters later.

5. Notify. Call the chain of command and the primacy agency within the required reporting window; do not wait until the event is resolved to make the first call.

Ordering rationale: exposure control and stopping the source are the only actions that reduce harm in real time. Investigation, repair, and paperwork can happen after the flow stops.

Notifications:

• Report the sanitary sewer overflow to the state primacy agency (CDPHE) within the required time frame in your system's SSO response plan - generally 24 hours for any unpermitted discharge. Report to the local health department and, if surface water is affected, the water quality agency.
• Public notification may be required if the discharge reached waters of the state, a public area, or a drinking water source; follow the plan and consult the agency on the same call.
• Notify downstream water utilities if there is a drinking water intake on the creek.

Documentation for each overflow point:

• Location, date, and time it started and stopped; estimated volume (use pump curves × run time, drawdown measurements, or the vac-truck ticket count) and the basis for the estimate.
• Description of the receiving water and how far the discharge traveled.
• Cause: rainfall and snowmelt, pump failure, capacity limit, or a combination - be specific and honest.
• Corrective actions taken during and after, and the steps planned to prevent recurrence.
• Photographs, sampling results if any, and a list of who was notified and when.

Then: file the required annual overflow summary. Regulators weigh the quality of your response and your follow-through heavily; a well-documented event with a real corrective plan is treated differently from a pattern of unexplained ones.

Separate the two problems first. Inflow is direct storm water (roof leaders, area drains, broken manholes, cross-connections); infiltration is groundwater and snowmelt entering through defective pipe, joints, and lateral connections. They need different fixes, and they peak at different times.

Data collection:

• Install temporary flow monitors at the lift station and at 3–4 key sub-basin points, then compare dry-weather, wet-weather, and snowmelt hydrographs. Nighttime dry-weather flow tells you the infiltration baseline; the spike in the first hour of rain tells you inflow.
• Nighttime and storm-event manhole inspections: look for submerged incoming lines, running joints, and clear-water flows.
• Smoke testing of the residential blocks, dye testing of downspouts, foundation drains, and sump pumps, and CCTV of the 8-inch clay main. Clay pipe from that era has failing joints and root intrusion, and the tap connections are usually the biggest single contributor.
• Check the manhole frames and covers on the low points; a single unsealed cover in the gutter can pass a huge flow.

Prioritization: rank by gallons removed per dollar, using measured flow response, not by pipe age. Typically: remove illegal connections and downspouts first (cheap, large effect), then seal manholes and frames, then spot-rehab joints and laterals, then mainline replacement.

Recheck: repeat the flow monitoring during the next snowmelt to prove the reduction before committing capital dollars.