Freeway pump stations maintained ahead of and during monsoon

PHOENIX – With a focus on the annual mid-June start of the monsoon in the state, the Arizona Department of Transportation is continuing its year-round maintenance of pump stations that remove storm runoff from many sections of Phoenix-area freeways.

ADOT technicians have some help in conducting safety-based maintenance inspections of the more than 50 freeway pump stations in the Valley. A drone is now being used to monitor for cracks, leaks, worn parts or other problems within pump stations.

The drone lets ADOT examine areas that are difficult for technicians to access, including upper sections of pipes that lift stormwater from a pump station’s storage well. The drone was first tested in February. ADOT expects the device will allow technicians to more than double the number of maintenance inspections they conduct each year. 

Pump stations typically operate with three or four engines and large pumps that they power. Crews conduct regularly scheduled inspections of the engines, including oil and fluid checks. They also conduct test runs of the pumps, which can be done even if there is no water in a station’s system.

Most pumps can lift more than 12,000 gallons per minute. That means an average pump station could empty a 35,000-gallon swimming pool in less than a minute. Still, strong summer storms that drop 2 or more inches of rain in an hour can challenge any drainage system. That’s why ADOT technicians monitor pump station operations and are prepared to respond to maintenance needs.

ADOT asks drivers to secure loads and not litter along freeways because debris that collects in drainage systems can block water flow and impact pump station systems. 

ADOT last year completed a new I-17 regional drainage project between Dunlap Avenue and Greenway Road that removed smaller, outdated pump stations at cross street interchanges in the area. The improved pipelines there use a gravity-controlled system to carry stormwater to basins and a flood channel.