Manvel planning commission recommends council allow limited pump detention for retail plaza with conditions

The Planning, Development and Zoning Commission on June 22 voted to recommend that the Manvel City Council approve a design-criteria modification allowing a pump detention system for a proposed 3-acre retail plaza on the south side of Croix Road and County Road 58.

City planning staff told the commission the request meets four of the five criteria in the city’s design criteria manual but must deviate from a requirement that pump detention systems be located at least 1,000 feet from residential properties. Staff said the proposal relies on gravity to handle about 77% of required detention and would use pumping for the remaining 23%, and that the applicant has proposed a natural-gas generator to power the pump system.

"So to conclude, the applicant meets 4 out of 5 requirements provided in the design criteria manual for a pump detention system," a staff member told commissioners, while noting the exception for the distance requirement. The project engineer, Karim Daghlani, said a siphon installed under a nearby irrigation canal — approved by the city and the canal authority four years ago — will convey the system outfall under the canal to a ditch rather than into the irrigation canal.

Several commissioners said they were concerned about the risk of pump failure and the potential for downstream flooding. One commissioner said pump systems have failed in other jurisdictions and urged caution, and another asked that the city reach out to the two homeowners located less than 1,000 feet from the proposed facility before the commission recommend approval.

Commissioner (S4) moved to recommend approval to council with two conditions: that Drainage District 4 sign off on the pump design and that the two nearby homeowners be notified; the motion was seconded by Commissioner (S7) and the commission approved the recommendation by majority vote.

Staff told the commission that Drainage District 4 approval will be required before a city permit can be issued and that the drainage district has its own review and monitoring requirements. The staff report included an aerial showing the proximity of nearby residences, a maintenance plan and a proposed maintenance covenant assigning ongoing responsibility for maintenance to the owner.

The commission’s recommendation is advisory; final action rests with city council and any permit issuance will require the separate approval of Drainage District 4 and compliance with city permitting requirements.

The commission made the recommendation during its regular meeting and transmitted the matter to council for final consideration.