Flood concerns eased in Cathedral City with new dam

A new Cathedral City flood control project is now providing flood control protection for the homes and businesses below it.

Engineers say the Eagle Canyon Dam has taken longer than expected to build, but is worth the wait.

It’s now providing improved flood control for an area along East Palm Canyon Drive that has seen damage from repeated flash flooding.

It’s still not complete, but it is on budget.

A raging flood most recently carried mud and debris across East Palm Canyon Drive on August 30, 2012.

Several businesses were flooded along with residents at the Tramview Mobile Home Park.

A similar flooding event also caused damage in July of 2008, but won’t likely happen again according to Robert Cullen, Chief of Design and Construction Division for the Riverside County Flood Control & Water Conservation District.

Cullen said about the dam, “It’s completely functional. It will work, we essentially have 100 year protection right now.”

The $8.9 million project eliminated the flood threat to the nearby homes and businesses from the rocky and barren hillsides above the city.

Construction was delayed by nearly a year because of a longer-than expected process to remove debris from an illegal dump and a practice target shooting range.

Builders also overcame some geologic concerns including different rock formations than expected near the dam and the discovery of three new earthquake fault lines.

The faults were discovered while crews dug the earthen structure out of the canyon.

The discoveries brought construction to a stand-still while geologists investigated and determined they were not considered active.

Geologists believe the faults haven’t moved in hundreds of thousands of years.

Cullen said the challenges were all easily mitigated with good engineering practices.

“Dam construction in particular, you have to deal with things as you find them,” Cullen said, adding, “there’s no way you can do enough investigation to determine every single variable.”

Even with the delays, the 85-foot dam structure is nearly topped out at 55-feet, its crest already stretching 370-feet across the canyon.

It’s capable of holding back up to 185-acre feet of flood waters and 14-acre feet of debris.

It will normally be dry, but can handle an inflow of water equal to filling 50-swimming pools every minute.

Below the dam, Deanna Sanders of Celebrity Consignment remembers rushing to keep water and mud out of her store August 30, 2012, the day before it’s grand opening.

She’s happy for the new dam.

“I think it leaves us a little more at ease, Sanders said adding, “hopefully we won’t get anymore rains. Hopefully what they’ve done so far is going to keep it at bay.”

Most of the soil hauled out of Eagle Canyon was put back into the dam structure.

It will now be topped off with huge boulders, also from the canyon, and stained to match the surrounding hill sides.

A second phase of the project, a $4-million pipe next year will connect the dam to the White Water River wash.

Cullen said, “as a result of this project and that outlet pipe we’ll be able to revise the Fema Flood plain.”

That will bring an additional benefit in the form of lower flood insurance rates for homes and businesses in the immediate area.