Mission approves plans for engineering, construction, financing of Rock Creek Channel improvements

Erosion of the Rock Creek Channel is causing this parking lot on Martway Street to fail.

Mission city leaders have given staff approval to begin steps for engineering, construction and financing of the Rock Creek Channel.

The Rock Creek Channel from just east of Nall Avenue to Roeland Drive has experienced severe erosion, and a subsidence to the parking area of the Roeland Court Townhomes occurred in August 2017, accelerating the conversation around the stormwater creek channel project.

After discussing the urgency of the stormwater project last month, the city council has decided to pursue making repairs to the entire channel all at one time.

“This allows for all existing issues to be addressed, and ensures that the improvements are coordinated and constructed in a clear and consistent manner,” City Administrator Laura Smith noted in city documents on the project.

This is what the parking lot looked like before homeowners made temporary repairs to the subsidence that occurred in August 2017.

The project includes design and construction of storm sewers, channels, retention basins and/or drains to manage the storm drainage, plus about 2,200 feet of retaining walls on both sides of the channel. Work also includes restoration of the parking area of the Roeland Court Townhomes.

Estimated construction and engineering costs of the project are $5.2 million. The city’s portion of the project is estimated at $4.8 million, and the Roeland Court Townhomes’ portion is estimated at $400,000.

The city will cover financing the project through the proceeds of about $4.2 million in general obligation bonds. The portion of the project costs related to the Roeland Court Townhomes will be repaid to Mission via the recently established Community Improvement District.

The first step includes design of the Rock Creek Channel improvements. The council on Wednesday unanimously approved entering a contract with George Butler Associates to design the project improvements at a cost not to exceed $694,500. The city’s stormwater utility fund will cover costs for design.

The council also unanimously approved plans for construction, engineering and financing of the project. There was no public comment or council discussion.

The city will now enter the design phase of the project, which is estimated to take 90 to 120 days. After that comes the process for bidding and contract awarding.

Smith said construction would take place after Jan. 1, 2020.

Editor’s note: This story has been updated to correct an error that incorrectly stated the cause of the subsidence of the parking lot. Engineers hired by the city found the subsidence of the parking lot was not caused by channel erosion, but by improper fill material used by the developer of the townhomes many years ago.