STUDY REPORT #1 ADDENDUM 1.0 PURPOSE OF ADDENDUM This document is an addendum to Study Report #1: Sub-System Planning Alternatives. The purpose of this addendum is to bridge the gap between the initial screening recommendations documented in Study Report #1 and the ultimate sub-area transportation plan that will be presented in Study Report #2. Since the initial screening recommendations were made in the first study report, several developments have allowed the study committee to continue to refine the alternatives. The result of gaining this additional information/refining the alternatives has allowed the study committee to screen out additional alternatives before moving into the detailed evaluation of this study, from which a recommended preferred sub-area transportation plan (Study Report #2) will be developed. The following sections of this addendum will review the initial screening recommendations from the first study report, alternative refinements since the initial recommendations, and identify those alternatives that are recommended to be screened out at this stage of the study before the detailed evaluation. 2.0 SUMMARY OF STUDY REPORT #1 SCREENING RECOMMENDATIONS Improvement alternatives selected for further study as a result of the initial screening process were categorized into three distinct groups based on the purpose and need for improvements and included: 1. Base System Improvements This group of alternatives is related to improvement alternatives identified through the study process to improve local continuity, connectivity and accessibility within the study area. Base system improvements include: a. Alternative D North/South Collector (see Study Report #1, Figure 14). 2. Improvements to Accommodate the Airport Master Plan Update This group of alternatives includes roadway realignments to accommodate the proposed airport runway extensions and the development of a future third runway as shown in the Airport Master Plan Update. These include: a. Alternatives A2, A3, A5.1 and A5.2 CSAH 16 West Realignment (see Study Report #1, Figure 11) b. Alternative B1 and B2 CSAH 8 Realignment (see Study Report #1, Figure 12) RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 1
3. Improvements related to the transition of TH 63 to a freeway facility This group of alternatives include the following improvements aimed at transitioning TH 63 to a freeway and meeting airport access needs as a result of the updated Airport Master Plan: a. Alternative C1.2, C2 and C3 TH 30 Realignment (See Study Report #1, Figure 13) b. Alternative E CSAH 16 interchange (see Study Report #1, Figure 15). c. Alternative F CSAH 16 east of TH 63 (see Study Report #1, Figure 16). d. Alternative G Local road connections to replace TH 63 access (see Study Report #1, Figure 17) e. Alternative H 60 th Street Overpass (see Study Report #1, Figure 18) f. I-90/TH 63 Alternatives Interim and Full Cloverleaf (see Study Report #1, Figures 23 and 24) g. Airport Access Alternatives i. AAA1 TH 63 Overpass and East Frontage and Backage Road (see Study Report #1, Figure 14 and 19) ii. AAA2 West frontage road along the west side of TH 63 (see Study Report #1, Figure 19). iii. AAA3 87 th Street Folded Diamond Interchange with Auxiliary Lanes (see Study Report #1, Figure 20). iv. AAA4 85 th Street Standard Diamond Interchange with collector/distributor system (see Study Report #1, Figure 21). 3.0 ALTERNATIVE REFINEMENTS SINCE STUDY REPORT #1 3.1 ADDITIONAL INFORMATION SOURCES Since the time the alternative recommendations outlined in Section 2.0 were included in Study Report #1, the study committee has continued to progress the study and has gathered additional information on the feasibility of these alternatives. This information has been gained through the following sources: Second Public Open House A second project open house was held on August 27, 2009, to gather public input/feedback on the range of alternatives identified and the initial screening recommendations. Jurisdictional/Agency Review Recommendations from Study Report #1 were presented to each of the local jurisdictions including Olmsted County, the Cities of Rochester and Stewartville, and High Forest Township in September of 2009. A separate meeting was also held to present this information to environmental resource and referral agencies. Community Advisory Panel Feedback The first Community Advisory Panel (CAP) meeting was held on October 26, 2009, to gather input/feedback on the range of alternatives identified and the initial screening recommendations. RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 2
Mn/DOT Geometrics Feedback A meeting was held on November 10, 2009, to review the initial alternatives and to allow for an opportunity for early feedback from Mn/DOT s Geometric Unit on the design workup of alternatives (i.e., general access spacing, general alignments and consideration of the design standards being used). Mn/DOT Aeronautics Input A meeting was held on October 15, 2009, with Mn/DOT Aeronautics, the Federal Aviation Administration (FAA), and the Rochester Airport managers/consultants to review roadway alternatives under consideration and to gain an understanding from Mn/DOT Aeronautics and FAA on what is permitted in terms of potential roadway realignments and new roadways within the various runway approach areas and land use safety zones. CSAH 16 Interchange Configurations Several interchange configurations were considered for the CSAH 16 interchange reconstruction by the PSC. These included a standard diamond configuration with traffic signals, a standard diamond configuration with roundabouts, and a folded diamond design. Environmental Path Feedback A response from Mn/DOT Central Office and FHWA indicated they were supportive of the proposal to develop an EA/EAW for improvements to the TH 63 South corridor between I-90 and 48th Street. This would include improvements to replace access to TH 63 as it is transitioned to a freeway in the future, and improvements to the CSAH 16 interchange, the I-90 interchange, and improvements to provide access to the airport (including TH 30). 3.2 REFINEMENT OF INITIAL SCREENING RECOMMENDATIONS Based on the additional information gathered from the sources outlined in Section 3.1 above, the PSC was able to further screen the initial alternatives and eliminate some of these alternatives from further consideration in the detailed evaluation phase of study. This section provides a review of alternatives recommended to be dropped from further consideration. Base System Improvements There are no base system improvements that were recommended to be dropped from further consideration in the detailed phase of evaluation. However, Alternative D, the base system improvement identified as part of this study providing a north/south collector connection east of TH 63 between Stewartville and Rochester, is not essential to the TH 63 improvements, but is assumed as part of the long-range vision. As such it will be assumed to be completed by others in the future when construction is more imminent and will not undergo any further detailed study in the next phase of evaluation. Improvements to Accommodate the Airport Master Plan Update 1. Alternative A CSAH 16 West Realignment Alternative A realigns CSAH 16 west of TH 63 around the proposed Runway 13/31 expansion shown in the Rochester Airport s Preferred Development Alternative RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 3
(February 2009). The need for and timing of this realignment is directly tied to the implementation of the Airport Master Plan Update. Therefore, it is not recommended that Alternative A (CSAH 16 West Realignment) be analyzed and evaluated in detail in the next phase of alternative evaluation since the timing of these improvements is unknown. This area may be considered for official mapping by Olmsted County and the City of Rochester as part of the last phase of this project in order to provide some level of protection against incompatible future development, but the PSC agreed the Airport would be responsible for identifying the ultimate alignment for CSAH 16 as long as it fell somewhere within the realignment swaths identified by the PSC. The Airport would also be responsible for the ultimate environmental documentation and funding for the construction of this realignment when needed to implement the Airport s Layout Plan. 2. Alternative B CSAH 8 Realignment Alternative B realigns CSAH 8 around the proposed future runway shown in the Rochester Airport s Preferred Development Alternative (February 2009). The Airport has noted the need for this additional runway is beyond their 20-year planning horizon. However, the future runway will be shown on their final Airport Layout Plan. Two CSAH 8 realignment alternatives were originally considered and documented in Study Report #1. Alternative B1 provided the minimal realignment necessary to accommodate the future runway by realigning CSAH 8 outside of the Object Free Area, but still within the Runway Protection Zone and Safety Zone A. Alternative B2 provided another option for realigning CSAH 8 completely out of the Object Free Area and the Runway Protection Zone, but within Safety Zone A. After meeting with Mn/DOT Aeronautics and Federal Aviation Administration (FAA), the study committee was advised that for new runways, roadways are not permitted in the Object Free Area or Runway Protection Zone, but are allowed in Safety Zone A. Due to this requirement, Alternative B1 which realigns CSAH 8 through the Runway Protection Zone was determined to be no longer feasible. Therefore, the study committee recommended Alternative B1 be screened out from further consideration. The need for and timing of Alternative B2 is directly tied to the implementation of the Airport Master Plan Update. Therefore, it is not recommended that Alternative B2 (CSAH 8 Realignment) be analyzed and evaluated in detail in the next phase of alternative evaluation since the timing of these improvements is unknown. This area may be considered for official mapping by Olmsted County and the City of Rochester as part of the last phase of this project in order to provide some level of protection against incompatible future development. The PSC agreed the Airport would be responsible for the ultimate environmental documentation and funding for the construction of this realignment when needed to implement the Airport s Layout Plan. 3. Alternative C TH 30 Realignment Three realignment alternatives for TH 30 between CSAH 8 and TH 63 were recommended to be carried forward for further study from Study Report #1. The realignment is necessary to accommodate the proposed runway extension shown in the RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 4
Rochester Airport s Master Plan Update. Alternative C1.2 provided the minimum FAA clearance requirements and provided east/west connectivity/continuity through connection to a TH 63 overpass. Airport access would come from an east frontage/backage road system or interchange for this alternative. Alternative C2 was found to also meet FAA clearance requirements with a runway shift. Airport access in this option would come from a west frontage road system. This alternative does sever east/west local continuity which will need to be evaluated further. Alternative C3 was similar to Alternative C1.2 except that it had a much longer reconstruction length in order to completely avoid encroaching on any designated runway protections zones. While the FAA is likely to support an option with less cost and impact, the PSC felt both C1.2 and C3 were feasible options and agreed to designate a swath between these two areas for further study in the future by others. Since the above recommendation for carrying a swath between Alternatives C1.2 and C3 was made, the PSC has continued discussion about the timing and feasibility of this type of realignment. The committee discussed the need to consider a realignment of TH 30 from TH 63 to CSAH 8 since the timing of the airport s runway expansion plans is unknown. The alternatives identified to reflect this realignment require substantial acres of new right-of-way acquisition and new roadway construction. Since the timing of the runway expansion, which would require the road realignment is unknown, the PSC recommended leaving the TH 30 realignment out of the EA/EAW for this project. The EA/EAW would include the tie in of TH 30 to a West Frontage Road, TH 63 overpass or the 87 th Street interchange. TH 30 west of this tie in point would then remain on the existing alignment from this point to the west to CSAH 8. Based upon this recommendation, Alternatives C1.2, C2 and C3 will not be evaluated in detail in the Task 8 analysis which will be documented in Study Report #2. Improvements Related to the Transition of TH 63 to a Freeway Facility 1. Alternative E CSAH 16 Interchange Configurations The initial screening for Alternative E (CSAH 16 interchange) evaluated a No-Build Alternative along with Alternative E1 which improved the existing CSAH 16/TH 63 interchange to an enhanced diamond interchange to correct the sight distance and skewed alignment issues as well as to provide adequate capacity for 2040. The initial screening recommendation was to carry forward Alternative E1 to reconstruct CSAH 16 as an enhanced diamond interchange; however, interchange configurations were not considered at the initial screening stage. Since Study Report #1 was published, the PSC has continued to explore options for the reconstruction of the CSAH 16 interchange. Three interchange configurations were evaluated including a standard diamond interchange with signalized intersections, a standard diamond interchange with roundabouts, and a folded diamond interchange. A preliminary traffic operations analysis and 2040 critical lane volumes were developed to analyze the feasibility of these three interchange configurations. The results of these analyses reveal that all of the configurations are able to handle the projected 2040 volumes and all are under capacity. Therefore, the difference among alternative configurations is really only related to right-of-way impacts. RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 5
The PSC considered the impacts of the three configurations and found the standard diamond configuration with signalized intersections had the most right-of-way impacts due to the required ramp intersection spacing for traffic signals. The standard diamond with roundabouts had fewer right-of-way impacts than the standard diamond with signals since the ramp intersections can be spaced closer together under the roundabout alternative and this alternative more closely follows the existing interchange footprint. The folded diamond configuration could work with either signals or roundabouts and has the benefit of allowing a direct connection to the east side frontage/backage road to the ramp intersection. Therefore, based on this discussion and analysis, the PSC recommended dropping the standard diamond configuration with signalized intersections due to the higher right-ofway impacts associated with this option than with the other interchange configurations. Study Report #2 will document the detailed evaluation of the CSAH 16 standard diamond configuration with roundabouts and the folded diamond configuration. 2. Alternative F CSAH 16 East Realignment The initial screening for Alternative F recommended carrying forward Alternative F1 which provided a new alignment for CSAH 16 east of TH 63 to provide for the ability to control access and meet the local access guidelines. The PSC further considered this recommendation and more closely looked at the existing access spacing along CSAH 16 east of TH 63 as well as the projected future traffic volumes in this area. Their conclusion was that the additional cost of correcting the access deficiencies with a new CSAH 16 alignment was not cost effective when considering the few number of accesses that were actually non-conforming. Therefore, the PSC recommended that Alternative F1 be dropped from further consideration. 3. Alternative G Local Road Improvements to Replace Direct Access to TH 63 There are no local road improvements (Alternative G) that were recommended to be dropped from further consideration. Each of these improvements will be considered in the detailed phase of evaluation. 4. Alternative H 60 th Street Overpass The initial screening for Alternative H recommended carrying forward Alternative H1 which provided an overpass to TH 63 at 60 th Street. The 60 th Street overpass provided local roadway connectivity/continuity across TH 63 between interchange access locations at 48 th Street and CSAH 16 for the future when the at-grade accesses to TH 63 are closed as this facility is transitioned to a freeway. Additional design and construction cost information was developed after the Study Report #1 recommendation. The estimated cost to construct this overpass was identified as $6.5 Million. The high construction cost was due to the topography of this area and the fill and retaining wall structures that would be needed to support the overpass. The PSC considered this information along with the estimated future traffic volumes on 60 th Street and determined this was not a cost RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 6
effective alternative for the low volumes projected to use the connection. Therefore, the PSC recommended that Alternative H1 be dropped from further consideration. 5. Airport Access Alternatives The initial screening for the Airport Access Alternatives documented in Study Report #1 recommended carrying forward a TH 63 overpass alternative (AAA1), a West Frontage Road alternative (AAA2), an 87 th Street Folded Diamond Interchange with Auxiliary Lanes (AAA3), and an 85 th Street Standard Diamond Interchange with a Collector- Distributor System (AAA4). Since the initial screening, the PSC further expanded upon potential options for a West Frontage Road alternative. Currently, there is insufficient space between TH 63 and the Object Free Area of Runway 13/31 for an at-grade West Frontage Road; in fact, the existing southbound lanes of TH 63 currently encroach upon a small corner of the Object Free Area. To address this issue, the study committee decided to study options for a West Frontage Road tunnel, an at-grade West Frontage Road alternative that shifts the southbound TH 63 lanes east, completely out of the Object Free Area and into the existing TH 63 median, and an option that would shift Runway 13/31 to the northwest to provide adequate width for an at-grade West Frontage Road outside of the Object Free Area. At the writing of this document, the PSC was further evaluating the benefits and costs of each of these West Frontage Road alternatives. The evaluation and recommendations of these options will be documented in Study Report #2. However, the study committee did receive additional information regarding the 85 th Street Standard Diamond Interchange with the Collector-Distributor (CD) System. After meeting with staff from Mn/DOT Aeronautics and FAA, it became apparent that this interchange location was not feasible since it would place structures within the Object Free Area and Runway Protection Zone of Runway 13/31. Therefore, the PSC recommended this alternative be dropped from further consideration in the detailed phases of study. In conclusion, the initial screening recommended carrying forward a TH 63 overpass, West Frontage Road, and 87 th Street and 85 th Street interchanges for future airport access consideration. However, as a result of additional information gained through meetings with Mn/DOT Aeronautics and FAA, the study committee agreed to carry forward the following airport access alternatives: TH 63 Overpass West Frontage Road Options o Tunnel o TH 63 Shift o Runway 13/31 Shift 87 th Street Folded Diamond Interchange with Auxiliary Lanes RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 7
6. TH 63/I-90 Alternatives The initial screening for the TH 63/I-90 Alternatives recommended carrying forward both an interim and an ultimate interchange configuration for this location. The interim improvement concept provides improved geometrics for north and south at-grade crossovers and ramp merges in the northwest and southeast quadrants. The eastbound I-90 to northbound TH 63 ramp is shown as merging onto northbound TH 63 at a point where northbound TH 63 traffic would be transitioned into one lane to allow for this merge condition. However, since Study Report #1 was adopted, Mn/DOT has further reviewed the interim concept for this interchange and has recommended only carrying forward the ultimate solution. Mn/DOT has identified the TH 63 bridges over I-90 as being replaced sooner than originally anticipated, therefore making the ultimate (full cloverleaf) interchange option more feasible. 4.0 NEXT STEPS The next step in this study is to complete the detailed alternative evaluation process on the remaining alternatives in order to identify a recommended preferred alternative plan for the sub area. The detailed evaluation and identification of a recommended alternative plan will be documented in Study Report #2: TH 63 South Corridor/Rochester Airport Sub Area Transportation Plan. Below is a summary of the alternatives that will be evaluated in detail in the alternative evaluation process: Alternative E CSAH 16 Interchange Options o Standard Diamond with Roundabouts o Folded Diamond Alternative G Local Road Improvements to Replace TH 63 At-Grade Access o North of CSAH 16, east of TH 63 o North of CSAH 16, west of TH 63 o South of CSAH 16 Airport Access Alternatives o West Frontage Road (TH 63 Shift) o West Frontage Road (Runway 13/31 Shift) o West Frontage Road (Tunnel) o TH 63 Overpass with East Frontage Road o TH 63 Overpass with East Backage Road o 87 th Street Interchange TH 63/I-90 Ultimate Interchange (Full Cloverleaf) Alternative RIA Sub Area Transportation Study/TH 63 South Corridor Preservation Plan 8