All of the Supplemental Draft EIS (SDEIS) alternatives followed the existing alignments with variations that shifted that alignment to the north or to the south each preserving different existing business and 4f properties. An aerial visual simulation was made to give stakeholders a good overview of the differences between the most likely alternatives.
The most viable alternatives included the north shift alignment for a new viaduct and the alternate known as the partial cover which located I-70 below grade with a cover. Two options were developed for the cover which was to be uses as a public park.
Its always a challenge to lay out such a large area of new roadway in an aerial simulation and keep everything in correct alignment with existing streets. We literally have to study and build the entire project in our mind within a few days and spill it out as organized pixels.”
M.P., POITRA Visual
Visual Simulations Project Manager
CDOT used their remote controlled aircraft mounted camera to provide the base photograph for the simulation.
POITRA plotted the varrious alternatives onto the base photograph using the existing streets and structures as landmarks. The existing viaduct was removed for all of the alternatives.
The conceptual plans were then used to determine which properties would be affected and to what extent. Each alternative affected a different set of residences, commercial buildings, trees, walks, medians and streets.
The new highway was painted as concrete and local streets were painted as asphalt providing a useful contrast. Pavement markings were applied as indicated by the Engineer. Automobiles and trucks helped give the simulated areas scale and believability.
Special effort and advance planning was required as POITRA artists created the illusion of depth when finishing the subgrade alternative of I-70 with the retaining walls and ramps.
POITRA later created a complete 3D model of the entire two mile subgrade prortion of the final Preliminarily Identified Preferred Alternative for the SDEIS public hearings.It was used to quickly expliain the design to the non-technical public.
POITRA displayed the simulations on the I-70 East EIS public involvement website at the request of the Engineer. The finished simulations were also used by CDOT in the I-70 East EIS public meetings, newsletters and as exhibits in the SDEIS Document.