Officials in four towns are celebrating the start of construction on one of the largest water projects in Colorado in years.

The Southern Delivery System project will build a pipeline, three pump stations and a water treatment plant to deliver water from Pueblo Reservoir to Pueblo West, Colorado Springs, Security and Fountain for an estimated $880 million. The next phase, which includes adding two reservoirs, won’t begin for several years.

Some work has already started, but city leaders and water officials are officially celebrating it Friday at the Pueblo Reservoir.

John Fredell of Colorado Springs Utilities says so far, the downturn in the economy is helping contain costs. He says bids to date have come in under budget by about 20 percent.