Alternative Longevity Issue

What is the longevity of alternatives? The alternatives may provide a reasonable service until 2030, 2050, or beyond, depending on the future travel habits. Currently, this Corridor has a very high car occupancy (2.6 persons per car). If that could be improved on, if more people would ride transit if such a mode were provided, or with yet to be seen travel intelligence, service into the long-term future is much more likely. Otherwise, some of the heavy demand of the Front Range for recreation in the Corridor may have to be foregone or travel habits shifted from weekend to weekday.

Why is the planning horizon set at 2025? Shouldn’t it be 2050 since CDOT’s current funding limitation cannot afford any action alternatives by 2025? Transportation planning is built on population and employment projections from local communities, metropolitan planning organizations, and the Department of Local Affairs (DOLA). These projections are developed in 20-year increments. At the time of the study, CDOT worked with these entities on their 2025 projections. CDOT has taken an additional step to look beyond 2025 making some basic assumptions about growth and travel habits to get at the larger question of 2050 due to the likelihood that transportation improvements will likely take until 2025 to be complete.

Screening and Environmental Impacts

Some of the eliminated alternatives and alternative components may have fewer environmental impacts than those included in the Draft PEIS. Alternatives retained for consideration at this Tier 1 programmatic level of study are considered reasonable and capable of being constructed in the Corridor. Some alternatives, including local tunnels or reduced shoulder widths that were considered to avoid sensitive features along the Corridor were eliminated due to anticipated construction difficulties. At the Tier 2 site‑specific level of study, FHWA may consider local design variances to avoid or minimize impacts.

Construction Impacts

Were construction impacts considered? At this Tier 1 level of analysis, only broad assumptions regarding the construction of alternatives have been developed. There would be a wide range of impacts in terms of potential traffic disruption and overall mobility along the Corridor as a result of the construction of alternatives. These impacts would typically be directly correlated with the overall width of the construction footprint, although there will be exceptions to this premise. Specific construction techniques and traffic management schemes would be developed during Tier 2 NEPA studies, project design, and construction planning. The PEIS has established the following interrelated assumptions at the Tier 1 level.

Construction of any alternative retained for full evaluation in the PEIS would be accomplished between the years 2010 and 2025. Implementing this assumption would necessitate completing Tier 1 and Tier 2 NEPA requirements and a meaningful amount of design work before 2010, so that some construction of a selected alternative from the ROD could begin by 2010.

Construction of any alternative would be phased in such a manner that the operation of the existing highway would be maintained throughout construction, although some limited interruptions to traffic could be expected during off-peak hours of operation. It is essential that traffic be managed through peak travel periods and seasonal conditions to meet the 15-year construction timeframe.

As indicated in the assumptions above, a premise of this study is that the highway would remain operational throughout the anticipated construction timeframe. This would require avoiding lane closures or reductions in the normal number of through lanes during peak travel times. During off-peak travel periods, reductions in the number of lanes, or even temporary total closures of the highway, would be inevitable due to construction activities that cannot reasonably and safely be accomplished any other way. Managing traffic during all stages of construction would be subject to detailed planning, including community involvement.

Advanced Guideway System (AGS) Issues

Why is the cost estimate of the Colorado MagLev Study much lower than the PEIS’s AGS alternative? Actually, the raw capital cost estimates of the AGS in the PEIS and Colorado Maglev research study are very similar. The PEIS’s raw capital cost estimate is $3,282 million and Colorado Maglev study $3,302 million. The difference of final cost estimates between PEIS and Colorado Maglev can be traced to various assumptions regarding contingency rates and the escalation factors that should be considered. The Colorado Maglev Project assumes a flat 25 percent for contingencies and does not individually address right-of-way, traffic control, mobilization, force account, utilities, environmental mitigation, permitting and preliminary engineering, and construction engineering costs. In contrast, the PEIS assumes 30 percent for contingencies, plus escalations of:

4 percent for drainage and utilities

1 percent for signing and striping

5 percent for construction signing and traffic control

7 percent for mobilization

2 percent for right-of-way

8 percent for force account, utilities, and miscellaneous items such as environmental mitigations (8 percent is applied to the escalated cost excluding right-of-way)

17 percent for preliminary engineering and construction engineering costs (applied to the combined escalated and force account, utilities and miscellaneous costs)

CDOT Division of Transportation Development (DTD) developed the above cost escalation factors based on CDOT’s various transportation projects. DTD has found that the final project costs on these various transportation projects were within the proximity of the cost estimate resulting from these escalation factors. Therefore, the $5.6 billion reported in the PEIS represents a reasonable estimate for the AGS. In addition, this cost estimating method was applied to all project alternatives. As with all other alternatives, an additional $500 million was added to the overall cost of the AGS for completion of minimal action components.

AGS's maximum traveling speed is actually greater than what is assumed in the PEIS. AGS-type technology speeds are limited by the safety and comfort of passengers while taking the tight curves in the Mountain Corridor at high speeds. Human tolerance to acceleration changes also limits the ability of the AGS to attain its maximum cruise speed between the proposed stations.

Cost Comparison

In capital cost comparison of alternatives, why is the cost comparison not done on a per mile basis? An alternative must be affordable to be considered reasonable. The capital cost of an alternative must be considered in its entirety because an evaluation of only cost per mile would not disclose to the public the true cost of implementation. However, a comparative measure of cost – cost‑effectiveness – was considered to help assess the financial implications of each alternative. Cost-effectiveness considers capital, operating and maintenance, person miles of travel, and farebox recovery. The cost-effectiveness indices for AGS are $1.19 per person mile compared to $0.68 to $0.75 per person mile for Highway alternatives, and $0.37 to $0.41 per person mile for Bus in Guideway alternatives.

Preservation Alternatives

What alternative components are preserved under the Corridor preservation alternatives? Preservation would be better defined once efforts to identify locally acceptable design solutions are underway. Preservation could be actually preserving space now for a future mode, locating walls and infrastructure so that the future mode could be provided, or purchasing the necessary land now for the future mode. On the other hand, we may decide to intentionally not preserve the actual space and/or infrastructure now so that impacts can be avoided or additional costs would not have to be incurred for many years.