Los Alamos County begins seasonal watering rules Friday, bans midday irrigation

Los Alamos County’s seasonal watering rule took effect Friday and immediately changed when homeowners, businesses and property managers can keep lawns and landscape alive through the dry months. Under the Department of Public Utilities rule, outdoor irrigation is off-limits between 10 a.m. and 5 p.m. every day, and watering is limited to specific days based on address through Sept. 30.

Odd-numbered addresses may water on Sunday, Wednesday and Friday. Even-numbered addresses may water on Tuesday, Thursday and Saturday. DPU says landscaping should be watered before 10 a.m. or after 5 p.m., a timing shift meant to cut waste during the hottest part of the day, when heat and evaporation make irrigation less effective.

The county said the restrictions are designed to reduce water use and ease strain on water pumping equipment. Water Rule W-8 applies to all DPU customers using produced or potable water for irrigation. It also classifies overflow onto streets, overspray onto streets, watering during prohibited hours and unrepaired leaks after five working days as water waste. Newly planted vegetation is exempt for one month, and the rule does not apply to gray water, rainwater, reuse water or private wells.

For Los Alamos households, the rule affects more than the lawn. It changes when sprinklers run, when garden beds are irrigated and how new landscaping is planned. For businesses and property managers, especially those with medians, entrances and common areas, the county schedule becomes part of daily maintenance. DPU has recommended automatic shutoff nozzles, timers, broom cleanup for driveways and sidewalks, and quick leak repairs to keep water where it belongs.

The policy also reflects a familiar local pattern. Los Alamos County has asked residents and businesses to curb outdoor watering during emergency conditions, including during the Cerro Pelado Fire in 2022, when DPU said outdoor watering could affect pressure in the distribution system. The seasonal watering program is part of broader conservation outreach, including Sustainable Landscape Design work with the Los Alamos branch office of the New Mexico State University Cooperative Extension. As summer heat builds across Los Alamos, White Rock and the rest of the county, the rule is one of the simplest ways the community tries to protect its water supply before daily demand and dry weather put it under more stress.