Canterbury Elementary hit by sewage backup after March storm; district, city engineers weigh fixes

Canterbury Elementary in Edinburg experienced a sewage backup after the March 27 rain event that left standing water in hallways, the library and the gym and prompted an overnight mitigation effort.

Dustin Garza, ECISD insurance manager, said Servpro crews began mitigation Sunday night at about 8:40 p.m. and worked until roughly 2 a.m. to disinfect and remove sewage water so the campus could open Monday. Principal Ricardo Perez discovered the standing sewage on Sunday when he returned to the campus to retrieve his laptop and notified district maintenance and facilities staff, Garza said.

Why it happened: Isael Posadas of SDI Engineering told the committee the campus sits at a lower elevation than surrounding streets and that district sewer lines tie into a city line that can become pressurized during flood events. "In my opinion, the reason that we had the issue with Canterbury ... is that this line was backed up, and what happened when the pump kicked on, it pressurized the system and increased the pressure in that line," Posadas said, describing water coming up through floor drains rather than toilets as a sign the problem originated off campus.

Immediate response and costs: The district hired cleanup contractors (pre-mitigation reported by Sherpro, cleanup by Servpro) and has removed and is replacing damaged building materials. Garza said the district submitted an insurance claim to the City of Edinburg's insurer; the city's maximum liability for the earlier event was $100,000 and district staff provided damage estimates including about $13,000 to repair glue-attached flooring and roughly $6,000 for library carpet replacement.

Next steps and options: Posadas presented two long-term technical options the district is exploring: rerouting the campus sewer connection to a different city line upstream of the pressurization point, or installing a backflow-prevention system and an on-site holding solution (for example, a temporary ~5,000-gallon storage tank or isolated manhole) so the campus can operate during off-site sewer surges. Posadas said each approach has trade-offs: a new tie-in may be the cleaner and less costly solution if elevations permit; an isolated backflow system could require on-site temporary storage and operational procedures if the city sewer is unavailable during an event.

City coordination and claims process: Committee chair Louie Alamillo told the board he had spoken with City Manager Myra Ayala and that the city agreed to meet after the engineer finalizes the report; Alamillo said the city planned to run camera inspections of its sewers. Garza said the district filed a claim and will pursue recovery through the city's insurer (TML). The city's prior payment for a similar September event was capped at $100,000, district staff said, and the district is seeking reimbursement for related mitigation and repair costs.

Board direction and district actions: Committee members repeatedly urged staff to move quickly. The group agreed to: (1) have SDI Engineering finish its report and recommendations, (2) meet with city staff and the city manager about potential tie-ins and camera work, (3) proceed with immediate campus mitigation and repairs, and (4) pursue the insurance claim with the city's carrier. District staff also said they will consider short-term operational changes at Canterbury (for example, storing pumps and covering floor drains) to reduce risk while a permanent fix is designed.

Why this matters: Canterbury serves about 703 students; board members said the duplication of two similar events within a year made faster technical solutions and clearer city coordination a priority. The committee emphasized protecting students and faculty and seeking cost recovery from the city while pursuing engineering solutions to prevent recurrence.