Cedars-Sinai has paused excavation on an emergency sewer holding tank at its Marina del Rey campus after a sewage-like odor drifted into surrounding neighborhoods for roughly six weeks, with the South Coast Air Quality Management District opening an active investigation, according to a report published 24 August 2026 (Yahoo). The hospital attributes the smell to groundwater mixing with storm-drain runoff during the dig (CBS News).
Key takeaways
- Cedars-Sinai says construction of a state-mandated emergency sewer holding tank is the source of the odor, and excavation has been paused "out of an abundance of caution" (CBS News).
- During excavation, groundwater has periodically drained into the site; the hospital says it is treated before discharge to storm drains but releases odor when it mixes with runoff (Yahoo).
- South Coast AQMD confirms it is investigating reported odor concerns, while Cedars-Sinai says investigators determined the odor does not fall within the agency's jurisdiction (Yahoo).
- Los Angeles County Public Works said the city of LA and its environmental department permitted the groundwater discharge, which is routed to a city of LA catch basin, and a city environmental team is working in the area (CBS News).
- Cedars-Sinai has apologized to the surrounding community and is coordinating with the Los Angeles Sanitation Bureau to resolve the issue (Yahoo).
What happened
Residents of a Marina del Rey neighborhood near Cedars-Sinai Marina del Rey began reporting a persistent sewage-like odor about six weeks before the 24 August 2026 report, with some describing nausea and headaches when windows were closed and air conditioning was running (Yahoo). Neighbor Craig Lightner told CBS News the smell "like a toilet" had spread across the marina, where he filmed murky fluid bubbling at the water surface and dead barnacles nearby (CBS News).
The hospital confirmed the source: a contractor is installing an emergency sewer holding tank on the southwest side of the campus, required by state law to keep the new hospital operational during a major earthquake or other natural disaster (Yahoo; CBS News). The hospital statement says: "During excavation for the tank, groundwater has periodically drained into the site and been treated before it flows into storm drains. The water has released an odor once it mixes with storm drain runoff" (CBS News).
Cedars-Sinai said it has paused excavation work and is working with the Los Angeles Sanitation Bureau, and a city of LA environmental team has been in the area, turning off the water flow while on site (CBS News). Los Angeles County Public Works confirmed the city and its environmental department permitted the groundwater discharge to a city of LA catch basin (CBS News). South Coast AQMD described its review as an "active, ongoing investigation" after receiving a handful of complaints, while Cedars-Sinai said investigators determined the odor does not fall within AQMD's jurisdiction (Yahoo).
Specification read
The sources do not report a daily flow, a tank volume, or influent load for the Marina del Rey holding-tank project, so any engineering sizing has to be framed in class terms. A state-mandated emergency holding tank sized to keep a new hospital operational after a major seismic event typically sits in the range of several hours to a few days of average institutional wastewater flow, with a class band of roughly 0.05–0.5 m³/day per bed (general industry range, not from the sources); total project capacity is therefore plant-specific and not derivable from this report. A project of this class — new-build hospital infrastructure with intermittent groundwater intrusion and permitted storm-drain discharge — sits at the screening/primary equalization and dewatering stages of the train, and dictates pre-discharge treatment such as oil–water separation, pH correction and dissolved-air flotation before any storm-drain or sewer tie-in. For procurement, the relevant buyer questions are: what equalization and pre-treatment stage is required upstream of the holding tank, who certifies discharge to the city catch basin, and what is the contractor's contingency plan when groundwater inflow spikes. Readers scoping a comparable Municipal or hospital package plant can compare a packaged Medical & Hospital Wastewater Treatment System (ZS-L Series) for screening-through-disinfection trains, and review the side-by-side guidance in DAF vs Clarifier for Plastics & Rubber Wastewater in Calhoun: 2026 Factory Guide for the pre-treatment stage the Marina del Rey incident is likely to require.
FAQ
What triggered the odor complaints at Marina del Rey?
Groundwater entering the excavation pit for an emergency sewer holding tank, which then mixed with storm-drain runoff after on-site treatment, according to the hospital (CBS News).
Who regulates the discharge?
Los Angeles County Public Works says the city of LA and its environmental department permitted the groundwater discharge to a city of LA catch basin, and South Coast AQMD has opened an active investigation into the odor (CBS News; Yahoo).
What is the tank for?
It is a state-law-mandated emergency sewer holding tank intended to keep the new hospital operational during a major earthquake or other natural disaster (Yahoo).
What should a buyer scoping a similar hospital holding-tank project plan for?
Class-level sizing is roughly 0.05–0.5 m³/day per bed (general industry range, not from the sources), with screening, equalization, oil–water separation and a DAF or clarifier stage before sewer or storm-drain discharge, plus a contingency for groundwater inflow during excavation.
