Denver officials have not agreed to a solution for Belleview & I-25


It has been nearly two and a half years since the most recent preferred alternative to address the traffic congestion at Belleview & I-25 was agreed on by eight out of the nine members of the executive committee of the I-25 & Belleview Interchange Improvement Study. The only member of the executive committee that is not on board with the preferred alternative is the City and County of Denver and nothing can be done unless and until a solution is identified with which Denver agrees. As time passes, the traffic problem worsens and the cost to address it increases, along with the exasperation of local government officials in Greenwood Village and Arapahoe County. 

This is an illustration of the Split Diamond alternative.

As far back as 2012, government traffic experts and elected officials recognized that the number of cars using the Belleview and I-25 interchange was growing at an increasing rate. That realization resulted in the first I-25 & Belleview Interchange Study, completed in 2016. No action was taken due to a lack of funding.

At the same time, construction at Belleview Station, a 55-acre, mixed-use, transit-oriented development adjacent to the Belleview Light Rail Station in Denver was starting in earnest. The master plan for the development anticipates that, at build-out, it will contain, “2.2 million square feet of office space, 300,000 square feet of retail space, 1,800 residential units, two hotels and more than five acres of plazas and open space.”

In 2018, a new Belleview and I-25 Interchange Study was initiated. Jeremy Hanak, Greenwood Village’s public works’ director who has been involved with this effort since its inception, told The Villager, “Here we are, four years later, with some analysis done, but really, no closer to an implementable solution.” 

This is an illustration of the SPUI alternative. Source: I-25 and Belleview Interchange Improvement Study completed 2020

That statement has been echoed in multiple settings by GV Mayor George Lantz and members of GV’s city council. In addition to the fact that eight out of nine voting members of the study’s executive committee and technical advisory committee agree on a preferred solution, many local officials believe that Denver has an overarching responsibility to make sure that this problem get solved because a recent study by Arapahoe County determined that, by 2040, 25% to 35% of all the traffic at the Belleview interchange will be attributable to the Belleview Station development. 

Under the plan called a Split Diamond, preferred by Denver South Economic Development Partnership, Colorado Department of Transportation, Cherry Hills Village, Federal Highway Administration, Denver Regional Council of Governments, and RTD, in addition to Arapahoe County and Greenwood Village, a new highway interchange would be constructed at Union Avenue. Using it, traffic going to and from the Belleview Station development would be able to access that area from Union Avenue, avoiding Belleview entirely. Union Avenue would also support multimodal travel options including bicycles, buses and pedestrians, but not in a manner that Denver finds acceptable.

The alternative favored by Denver is called the Single Point Urban Interchange (SPUI). It would leave Union Avenue unchanged and require the bridge at Belleview and I-25 to be completely removed and replaced. This plan would take two to three years to build, during which time traffic on Belleview would be disrupted. 

Hanak pointed out, “This issue is very important to Greenwood Village. The city has three I-25 interchanges and Belleview is the most problematic.” 

The city boundaries of Denver only extend south of Union Avenue up to Belleview between Monaco Street and Yosemite Street, so one can imagine why this issue might not be as much of a priority for Denver officials.

The Split Diamond alternative could be built, and funded, in phases, and would not cause any disruption on Belleview. Still, Kendra Black, Denver City Council Representative for the area that includes Union Avenue and the Belleview Station development told The Villager, “Denver does support the SPUI as—according to traffic engineers—the benefits will be nearly the same as the Split Diamond AND it will allow Union to remain a multi-modal street which is what Denver residents want.”

The Villager asked Hanak why this situation has evolved into a stalemate. He explained,  “On the north side of Belleview, you have the City and County of Denver that has fundamentally different beliefs, how they want to handle not only transportation, but land use planning overall. South of Belleview, you have Greenwood Village and Arapahoe County with a drastically different take on transportation and land use planning. You can see it with the development. North of Belleview, there are tall buildings with no setbacks. South of Belleview, you see setbacks and lower building heights.” He continued, “Denver says they are planning for a full multimodal transportation environment. Greenwood Village has a great trail system and bike lanes, but not on every street.”

He continued, “The Split Diamond would utilize the Union Street overpass to connect ramps to and from I-25, connect down to Belleview and down to I-25 again. It would have the impact of removing up to 20% of the traffic from Belleview, so little would need to be done there…. That alternative was shown to handle traffic better with shorter delays, and a better level of service. It would also allow us to keep Belleview open while the ramps are constructed. Being able to phase it is also important, because it allows us to build it as funding becomes available instead of having to have $110 million all at once…Neither the technical nor the executive members of Denver’s team have ever agreed with the Split Diamond alternative because they say it has too many impacts to multimodal—the bikes and pedestrians—on Union Avenue.” 

In order to address Denver’s concerns, Hanak told us that the technical team “spent an entire year looking at multimodal enhancements to Union, so it still had a ten-foot sidewalk, a bike lane at the same level as the sidewalk, a transit lane just for buses, in addition to vehicular lanes.”  

Denver still objected, he explained, because the Split Diamond alternative requires Belleview traffic to get off at Union and use the ramps to get to Belleview. Currently, southbound I-25 traffic that uses the Belleview exit exits I-25 north of Union but uses an underpass to reach Belleview, so it does not impact Union. With the new design, there is no room for that underpass. It is that additional traffic that Denver has cited as being unacceptable to the bicycles and pedestrians it envisions using Union because, they “want to make it a bike and pedestrian corridor.”

From the viewpoint of Greenwood Village and other funding partners, the Split Diamond alternative offers adequate bicycle and pedestrian access, as well as buffering for multimodal users, including a bus lane, even though RTD has no current plans to bring buses back to Union at nearly the volume they ran previously.

On July 11, GV Mayor George Lantz said that at a recent meeting, representatives from the City and County of Denver, “Once again reiterated that the bridge over Union Avenue that was built for the purpose of offloading the Belleview interchange and was given to them (Denver)—now they have a policy that precludes the use of it for anything that would be detrimental to multimodal use, such as having cars use the bridge.” He added, “They (Denver) are pushing hard for the solution to be a complete removal of Belleview and I-25, a rebuild of I-25 for a half mile in a two to three-year project that would have significant impact to the traveling public and, in my opinion, would have significant impact to the businesses in our community…After two and one-half years, we remain at a stalemate.” 

Currently, one can hardly drive through Belleview Station because of the ongoing construction of the Vectra Bank headquarters, Klimpton Hotel (190 guestrooms plus amenities), and other ongoing construction. Added to that, on June 6 Denver City Council approved a new policy that requires any new residential development with ten or more units to designate between 8% and 15% of those units as affordable housing, effective July 1. Submitting plans before that July 1 deadline, possibly to avoid that requirement, were four new developments in Belleview Station: 

4702 S. Newport St – 17-story office building with approximately 421,000 square feet and 1,137 parking spaces

4704 S. Newport St – 20-story building with 190 apartments and 262 parking spaces

6700 E. Union Ave – 19 and 20-story tower, 2-phase, 700-unit apartment building with approximately 25,000 square feet of grocer on the ground floor and 950 parking spaces.

Bordered by Niagara Street, East Layton Street and East Chenango Avenue, the two-acre site is planned to include a concrete structure with approximately 150 for-sale market-rate condominiums, 300 parking spaces and +- 5,000 square feet of ground floor retail and/or activated space.