Dam project awaits parts, inspectors

Chad Frey
Sand Creek will fill again after a project to replace a dam south of First Street. The dam failed about a year ago, and contractors are awaiting parts and inspectors before moving forward.

Sand Creek has remained pretty dry for nearly a year, the result of leaks in a dam to keep waters up.

“This is not a flood control item, it is for aesthetics, especially,” said Suzanne Loomis, director of public works for the city of Newton, in 2019. “The purpose of this is to have a pool of water that is aesthetically pleasing around town.”

The dam makes use of an inflatable bladder, which city staff and engineers told the commission last year is a cost-effective way to manage the water pool and deal with water rights downstream.

The dam failed in July 2019. At 40 years old, with a life expectancy of 20 years, city parks staff noticed the rubber bladder on the adjustable inflatable dam appeared to have a problem on the north side. The air inflation equipment was now struggling to keep up, which indicated a significant leak.

Replacement will move forward soon — the new bladder was delivered June 26. According to city manager Kelly McElroy, glue, sealants and piping are supposed to arrive sometime after July 7.

There is one big wrinkle, the bladder manufacturer, Dyrhoff, requires a company inspector to be on-site during installation for the product warranty to be valid, but current travel restrictions for COVID-19 prevent the UK-based inspectors from entering the United States.

“Once installation begins, it is anticipated to take about a week,” McElroy said.

In late November the commission awarded a design and build contract Dondlinger Construction for replacement of the Sand Creek Dam.

The contractor expected four to six months before delivery of the new bladder. The contractor will remove the old bladder to asses the condition of substructures of the bladder and dam.

The cost of the project is estimated at $400,000, with the capitol improvement budget allowing for $600,000. A concrete dam with multiple gates was estimated to cost more than $2 million by engineers working on the project.

Life expectancy of the bladder is 20 to 25 years. The original bladder lasted for 40 years.

This will be a bonded project, with the bond payments made out of the sewer budget.