Impacts on Adams County of Rerouting I-70 along the I-270/I-76 Corridor
“Image” is the first criterion people use to assess the appeal of a place. A cutting edge 21st century interstate redevelopmentand expansion of a design quality equal to or surpassing Vail Pass, Glenwood Canyon and T-Rex on which people would pass through the southern portions of Adams County, Commerce City, Jefferson County and Arvada, adjacent to Wheat Ridge and Lakeside, would transform the nationwide perception of these communities.
At present, I-270 and I-76 are stepchildren in the eyes of the public and the Colorado Department of Transportation. For example, Don Hunt has just announced that his current plan is to segment the East I-70 project and to only build the portion between Brighton Boulevard and Dahlia Street in the first phase. The widening between Dahlia Street and Tower Road will be delayed. Although Mr. Hunt doesn’t say so, this means that the required improvement and widening of I-270 will be lowered one notch on the priority scale and may not be undertaken in the foreseeable future even if MPACT64 is approved by the voters. Rerouting I-70 along the I-270/I-76 corridor would make the improvement of the highway through Adams County and Jefferson County CDOT’s top priority and would allow it to be completed at a much earlier time.
Contrary to information provided to Adams County by the Colorado Department of Transportation, rerouting I-70 along I-270 and I-76 would only require widening the highways to a maximum of five lanes in each direction.
Thus, the traffic engineering industry's "bible" is called the Highway Capacity Manual (HCM), published from time-to-time by the Transportation Research Board (TRB.) Here area few facts researched by TRB and others:
- The one-hour"base" (i.e., comfortable, Level of Service C, etc.)capacity of one lane of urban freeway is 1,500 vehicles per hour per direction. This can vary a little bit due to percent trucks, grades, curves, etc., but everyone likes and uses 1,500 for freeway planning purposes. By the way, it used to be 2,000, so 1,500 is considered conservative,
- Peak one-hour traffic is almost always 10% of24-hour weekdaytraffic, or ADT. This also can vary a little bit, but everyone likes to use 10% for freeway planning purposes.
- The maximumADT forecast of I-270 and I-76 among all the Reroute scenarios CDOT produced is 140,000 and125,000 vehicles per day in two directions, respectively,or 70,000 and 62,500 vehicles inone direction. This of course means 7,000 and 6,250 vehicles in one direction in the peak hour, respectively.
- So, usingthe generous one-way capacity of one freeway lane of 1,500 vehicles per hour per direction, we would need 4.6 lanes per direction for I-270 and 4.1 lanes per direction for I-76. Obviously, we can't build a fraction of a lane, so let's be generous (again) and go with 5 lanes in each direction for each freeway, or 10 lanes total. It doesn't matter if some of these lanes are managed, tolled, HOV and/or truck lanes. The math is always about the same.
Exaggerating the number of lanes that the Reroute Alternative will need is just another CDOT attempt to make the Reroute Alternative less attractive than the Trench Alternative. No existing or planned freeway in Colorado today has 12 continuous through lanes of highway, and very few cities in the US, if any, have that many continuous miles of Interstate highway built that wide.
Rerouting Interstate 70 along the I-270/I-76 corridor would not have any negative impacts on that Adams County Transit Oriented Development Vision Plan The planned Federal Boulevard station is approximately one-quarter mile north of I-76 and the highway widening would occur on right-of-way already owned by the Colorado Department of Transportation north of the proposed Pecos Boulevard station.
To the contrary, all of the developers with whom we have spoken believe that the land along I-270 and I-76 is underutilized with a mix of vacant land, refineries, waste disposal plants, cement and asphalt manufacturing plants and quarries. Much more appropriate and high value allocation of such land in close proximity to a major highway in a semi-urban area would be mixed use office and light industrial development such as exists along I-25 at the Tech Center and U.S. 36 at Interlocken. The closure of current I-70 through Denver and the development of the I-270/ I-76 corridor as the major east-west I-70 travel route, along with the improvement of this roadway to a state-of-the-art highway such as that going through Vail and Glenwood Canyon could spark this type of development.
State-of-the-art replacements and new interchanges at Vasquez/Colorado boulevards into the nearby Dog Track renewal project and from scratch at Brighton Boulevard would create true gateways into Commerce City.
Additional modifications and upgrades at Pecos, Federal and Sheridan are outstanding opportunities to provide better access and beautification into Adams County, similar to the exceptional bridge and landscape designs serving Westminster, Broomfield, Flatirons, Louisville and Rock Creek along U.S. 36 to Boulder.
Proper construction design also would facilitate access to Northfield Mall and Dick Sporting Goods Park, increasing commercial activity.
The improved traffic flow associated with a better designed and constructed highway will improve air quality throughout Adams and Jefferson counties. Backups and congestion are major causes of pollution. Unlike the current I-70 route there would be minimal road gradients, lesser curvatures, higher speeds and safer roadway geometries while being located in constant sunlight, out of snow shadows and with easier maintenance for weather recoveries. Overall environmental quality will be further improved by the attraction of less polluting business activity to the area. As the environment is improved integrated water basins, hiker/biker trails and upscale landscaping can occur similar to that along RTD’s West Line.
Proper design will allow all local surface streets, sidewalks, greenway, bike/hike trails to continue and enhance connectivity (e.g. Midtown to Pecos RTD station), and open new routes to be established where needed for improved mobility and to permit co-joining of neighborhoods. This would stimulate multiple neighborhood revitalizations.
As part of CDOT’s mitigation requirements related to the construction of the new highway, they would be required to relocate Adams County schools and day care centers within the FHWA interstate highway air pollution impact area.