County unveils plan for 179th Street improvements

Roundabout, turn lane added as part of overarching road improvement plan

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Clark County residents were able to virtually view some of the first road improvement projects for Northeast 179th Street, located east of the county fairgrounds, that were featured in a larger plan addressing the anticipated growth in the area.

On Jan. 27, Clark County hosted a virtual open house for projects set for 179th Street’s intersections with Northeast 29th Avenue and Northeast 50th Avenue. Attendees also had a chance to hear about the county’s 179th Street Management and Circulation Plan, which will see a slew of planned improvements in a section of the county poised for growth.

Clark County Public Works long-range transportation planner Matt Herman explained the plan was designed to create a safe and predictable transportation network that is well-connected. The overarching plan spanned road improvements along 179th Street from Northwest 11th Avenue to Northeast 50th Avenue.

Development in the plan’s area has not occurred since 2007 due to an urban holding overlay placed upon it by the county which was lifted in 2020, Herman said.

“We’re really on the cusp of redevelopment of the neighborhood and we want to make sure we have a local transportation system that is planned,” Herman said.

The plan features widening of 179th Street, additions of arterial roads connected to the street, removals of some roads and realignments. The plan also features the addition of more than a dozen roundabouts, all but one along 179th Street.

Herman stressed the roads planned in places currently owned by private property owners would happen later on.

“These local streets are built by development. They are not built by Clark County,” Herman said.

The plan encompasses a long-range effort and does not include a specific construction plan like the intersection improvement projects featured at the open house. Those two projects included one of the circulation plan’s roundabouts and an addition of turn lanes on another.

Clark County Public Works Capital Projects Manager Scott Sawyer said the county initially moved swiftly with improvements to 179th Street once the urban holding designation was removed.

“We knew it was important to get this construction going and get some of these improvements in place because we knew that development was going to be occurring,” Sawyer said.

A change in leadership at the county-level led to a reconsideration of the project’s scope, as Sawyer explained a “bigger, holistic view of the corridor” was needed, especially with consideration to projects closer to the Interstate 5 interchange.

The project closest to the interchange of the two projects discussed features a roundabout for the 29th Avenue intersection. Currently a four-way stop about a mile from the interstate, the roundabout will initially be striped as a single lane, though it could be converted to two lanes with a buildout if traffic flows warrant it.

“The extent of traffic we have right now only warrants a single-lane roundabout,” Sawyer said. “However, what we don’t want to do is have to come back in and widen at a future date. … We’d rather do it all at one time.”

DKS Associates Senior Traffic Engineer Randy Johnson said both a traffic signal and roundabout are under consideration for the intersection.



“Safety is the real driver here,” Johnson said.

Roundabouts generally have three times fewer injury and fatal crashes when compared to intersections because of slower speeds and the nature of collisions typically experienced in those intersections.

Based on traffic forecasts, the roundabout would perform better than a traffic signal, Johnson said. Maintenance costs would also be lower.

Current projections show the single-lane setup would be sufficient for up to 20 years, Johnson said. The planned construction would allow for just the 179th Street approaches to be increased to two lanes if that is needed to meet traffic demands.

“It’s a really flexible design and it’s a really cost-effective way to expand into the future,” Johnson said.

The roundabout would fully accommodate semi truck traffic, even for U-turns, Johnson said.

The 29th Avenue project is expected to cost roughly $23.2 million, according to the adopted Clark County Transportation Improvement Plan for 2022 - 2027. Sawyer said the project would be funded through a federal grant, traffic impact fees paid by developers, money from the county road fund and funding from Clark Public Utilities for utility infrastructure.

Sawyer said property acquisition is expected to begin in April and continue through March 2023, with bids for construction opening in the spring of 2024. Substantial completion of the project is expected by summer of 2026.

For 50th Avenue, the intersection will remain an all-way stop, but a left-turn lane on both directions of 179th Street onto 50th Avenue will be added.

Initial plans stated the intersection would be developed with an expandable roundabout similar to what is set for the 29th Avenue crossing, Sawyer said. During the county’s reassessment, it was determined the need isn’t there.

“Eventually it will need to go in,” Sawyer said about the roundabout for 50th Avenue.

He said analysis by traffic engineers showed adding the turn lanes would be sufficient well into 2035.

“The decision was made that rather than spending a considerable amount of money putting in a roundabout at this time, the money would maybe be better well-spent moving that closer to the interchange,” Sawyer said.

The 50th Avenue project is set to cost about $15 million, according to the county’s current transportation improvement plan. Sawyer said it would be paid through mostly county road funds.

The 50th Avenue project is less intensive than the one at 29th Avenue. It will only require the addition of asphalt onto the road shoulders and re-striping. The land acquisition process is set to begin in December and wrap up by the end of 2023, with project completion set for fall of 2024.