The Town Council has approved $2.2 million for a project to replace a drainage line along Panorama Drive across from Fountain Park. The council voted 7-0 at its Aug. 24 session to award a $2 million contract to Blucor Contracting. The additional $205,000 is an owner’s allowance to cover possible contingency expenses with the project.

There are five street or drive access points in the path of the replacement project. Public Works Director Justin Weldy said every effort will be made to minimize interruptions for residents and motorists who use the street.

The storm drain was originally constructed by MCO Properties prior to incorporation of the town. It was done in conjunction with the paving of Panorama Drive. The drainage line is primarily 48-inches in diameter and runs approximately 3,000 feet from just east of Saguaro Boulevard to past El Lago Boulevard. The drain is 66-inches at the far end.

In a report to the council on the proposed project, staff reported that dry weather flows are frequently noted in the wash channel downstream from the pipe outlet. Although a source for those flows has not been identified staff reports the water indicates the likelihood of a drainage flow in the pipe’s trench bedding and/or backflow. Water adjacent to the metal pipe vastly increases its corrosion potential. In 2015-2016 the town hired a contractor to clean the drainage which was found to be half filled with sediment.

In January 2020 a sinkhole was discovered at the surface adjacent to the pipe, and later a second sinkhole appeared. It was discovered that the bottom of the pipe had been corroded away and there was a large hole above the pipe for a 20-foot length. Those sections of the pipe were removed, replaced and backfilled.

Following those failures, staff had a camera inspection performed of the entire pipe length. The camera revealed numerous locations where the bottom of the pipe was missing, corroded areas and substantial areas of missing pipe lining. There were also areas of the pipe that had to be skipped due to its condition.

Staff reports that due to the poor condition of the pipe a non-structural slip-line repair of the piping was not feasible. The entire length of the drainage pipe needs to be replaced with a corrosion resistant pipe material.

Town officials are also concerned that failure of the line could cause street pavement and sidewalk failures that could increase the costs of repair.

Six contractors bid for the work with a range of about $1.4 million. The Blucor bid is the lowest. The company has been doing work in Fountain Hills for Toll Brothers in the Adero Canyon development.