City approves repair project for Encino Drive
The City Commission approved the $557,289 contract to United Materials for repairs to Encino Drive.
The road has been problematic for years, according to residents and the city.
City investigations into the issues with the road determined the poor quality of the road was the cause of many of the issues, according to the city staff report.
That raised some questions for The Electric, our readers and at least one commissioner.
Over the weekend, Commissioner Bill Bronson sent a list of questions to Public Works related to the history of the road and the inspections. The Electric asked similar questions. Public Works staff compiled some historical information on the project.
Encino Drive and a few other projects in the 1990s caused the city to revise the city’s inspection policy in 2004 and since then, city inspectors have been performing those duties on private development.
The area that includes Encino Drive was the second supplement to the Grande Vista subdivision, which was platted and annexed into the city by Roy Volk and partners in 1984-85, according to city records.
A 1984 geotechnical report showed high groundwater and fat clay soils. The area has historically been a very wet area, according to Public Works.
Gary Knutson later bought and developed the subdivision.
A 1994 geo-tech report did not show groundwater but warned of it, according to Public Works. That report also gave some recommendations for dealing with the clay soils for better stability in the road.
Construction of Encino Drive was done in four phases between 1995 and 2002.
The original designs were done by Delta Engineering, according to city records, and called for 3 inches of asphalt over 12 inches of road base on top of 6 inches of compacted subgrade.
That was a pretty standard road design at the time, Dobbs said, “but obviously some things got overlooked in the construction that the developer supervised. The design was also inadequate for the area.”
At the time, city policy was to have registered professionals design the roads and there was a provision that required qualified inspectors to be on site at all times, according to Dave Dobbs, city engineer.
“That caused a lot of problems,” he said. “There was a lot of cutting corners back then.”
This subdivision and a few others pushed the city to change policy since a lot of poor quality infrastructure was being built, particularly roads, Dobbs said.
Encino Drive started deteriorating rapidly, Dobbs said. Alpine Drive was another one that caused issues.
“Those were really the impetus to change city policy,” he said.
At the time, the city did approve street designs, Dobbs said, and trusted the engineers since they were also professionals. But, the roads weren’t always turning out well.
In the case of Encino, the subgrade wasn’t compacted properly, which has caused many for the ongoing problems with that road, Dobbs said. For Encino, Dobbs said there were failures in design and the construction process and the city could have been more vigilant at the time.
“That’s why we have full-time inspectors now,” he said.
Delta Engineering, which was owned by Knutson, the developer, was responsible for the inspection of all of the phases, according to Public Works. United Materials constructed a portion of the road in 2002, according to city records.
Dobbs said the original street designs were used and some of the city’s later recommendations were not used by the developer. Delta staff did the inspection and records of those inspections are incomplete since it was a private project at the time.
“Onsite inspection usually finds problems in the course of the work so they can be addressed. Apparently this did not occur,” Dobbs said.
Stormwater mains were installed in the area in 1995 under Delta’s inspection and additional storm drains were installed by the city in 2008 along Flood Road and connected to the Grande Vista storm drains. Those improvements helped alleviate the uphill surface water from entering the area, but would not have addressed the groundwater issues, according to Public Works.
For the current design, the city hired Terracon in 2017 for the most recent geotech report. Strip drains are being installed as part of the city project to intercept groundwater from entering the road, according to Public Works.
Specifications for the current project are all available on the city website in the invitation to bid.
During Tuesday’s commission meeting, Bronson said there was a good chance that had city inspections been in place in 1996, they might not be incurring the cost of a major repair now.