City officials are gearing up to revamp one of the city's most congested intersections, though a full-scale fix is still a long way off.
Littleton recently landed a $9.1 million federal grant to overhaul the intersection of Santa Fe Drive and Mineral Avenue, Public Works Director Keith Reester told a city council study session on July 23.
Addressing problems at the crossing is a top priority for city engineers, Reester said.
“This is one of the most challenging and highest-accident intersections in the city,” Reester said. “Traffic could get even higher with new development growing to the south.”
City engineers have settled on a plan for the grant, Reester said: a “quad-road” interchange, which will add a sort of mini-beltway on the southwest and northwest corners of the intersection, redirecting much of the traffic that currently lines up to turn left in the center of the intersection.
The change could add as much as 60% to the total capacity of the intersection, Reester said.
“If nobody ever turned left, intersections would go really fast and work awesome, but we do that,” Reester said.
The intersection currently sees about 90,000 vehicles a day, according to city data, which could climb to 120,000 by 2040 — or even higher as developments like Sterling Ranch in Douglas County grow, as well as planned multi-use developments currently in the works at the southwest corner of the intersection.
Construction on the intersection likely won't start for a couple more years, Reester said, because the city must complete designs for the expansion, and must negotiate with landowners for rights-of-way. RTD owns the area where the northwest ring road would be built, and it would have to be incorporated into the light rail station infrastructure.
The southwest portion would run through the old Ensor property, now slated for development by Evergreen Devco.
Evergreen is working with the city to integrate the road expansion into its property, Tyler Carlson, one of the company's managing partners, said in June.
“Our residential planners aren't thrilled to have a whole lot of extra traffic through the site,” Carlson said. “On our retail side, though, it's great. The more cars past our stores, the better. At the end of the day it's just the right thing to do.”
The ultimate goal, Reester said, is to build a grade-separated interchange, or flyover with no stoplights, similar to the intersection of Belleview and Santa Fe, though that project is expected to cost $90 million to $100 million, and is likely years away. It will require a Herculean effort to raise funds and bring all stakeholders into agreement, he said.
However, Reester said, the city is moving forward on a precursor to the future flyover: Funding has been finalized to begin a Planning and Environmental Linkages study, or PEL, on a stretch of Santa Fe from Alameda Avenue to C-470.
The project involves eight different entities, Reester said, including Denver, Douglas and Arapahoe counties, as well as Sheridan and Englewood — all governing bodies the stretch of road passes through.
The idea is to undertake a large-scale, holistic study of the whole corridor, to ensure that any road upgrades undertaken by municipalities fit into an effective larger framework, Reester said.
The total cost of the study, which is expected to kick off next month and last two and a half years, is $3 million — 50% of which will come from federal funds, with Littleton's share of the remainder at $165,000.
Participating in the study is vital to making sure that upgrades made by the Colorado Department of Transportation fit in with Littleton's needs, Reester said, citing a recent example in which CDOT engineers wanted to reduce left-turn opportunities along Santa Fe through Littleton, which would have reduced access to local businesses.
“For CDOT, their goals are travel and safety, and obviously those are high priorities for us too," Reester said, "but we also need to convey to them our corridor character and how that impacts our community.”
This video by the Virginia Department of Transportation gives an overview of how a "quad road" intersection works: