From Las Cruces to London, Cities Fight a Common Enemy: Grease in the Sewers

LAS CRUCES — It may not be the most glamorous responsibility in municipal government, but keeping restaurant grease out of the sewer system is part of a worldwide effort to protect wastewater infrastructure, prevent sewage overflows and reduce costly emergency repairs.

The City of Las Cruces recently recognized its Code Enforcement Officers for working with the Industrial Pretreatment Program to bring restaurants into compliance with the city’s Fats, Oils, and Grease Ordinance.

James Woods, the city’s Utilities Pollution Prevention Manager, credited the partnership with helping ensure local businesses maintain required grease-control measures.

“This partnership helps protect our wastewater collection system by reducing the risk of sewer blockages, sanitary sewer overflows, and other issues caused by improper grease disposal,” Woods said.

The problem extends far beyond Las Cruces.

Cooking fats and oils can enter sewer systems as liquids, then cool, accumulate on pipe walls and combine with other waste to restrict wastewater flow. The resulting blockages can send untreated sewage into buildings, streets and waterways.

The U.S. Environmental Protection Agency has identified grease as a major contributor to sewer blockages nationwide. In an earlier assessment cited by the agency, grease from restaurants, households and industrial sources accounted for 47 percent of reported blockages.

In London, the problem has produced enormous underground masses known as fatbergs, formed when grease binds together discarded wipes and other materials.

In October 2025, British utility Thames Water announced the removal of a 100-tonne fatberg stretching 125 metres through a sewer in West London. The obstruction required more than a month of work to clear.

Although such extreme examples attract international attention, smaller grease accumulations can cause serious problems in ordinary municipal sewer systems.

Restaurants are particularly important to prevention efforts because commercial kitchens regularly handle cooking oils, animal fats and other grease-producing materials. Grease traps, interceptors and proper disposal practices help keep those materials out of public sewer lines.

In Las Cruces, the partnership between Code Enforcement and the Industrial Pretreatment Program addresses the problem before it becomes an expensive underground emergency.

Woods thanked Code Enforcement Officers for their continued assistance in bringing restaurants into compliance.

“Your efforts make a real difference in keeping our community's wastewater system safe, reliable, and operating as intended,” he said.

The recognition highlights a largely invisible municipal responsibility: protecting the infrastructure that carries wastewater away from homes and businesses, one kitchen drain at a time.