University Region FY 2023 Final Scoping Package

Transcription

1 September 30, 2016 University Region FY 2023 Final Scoping Package I-496/US-127 Scoping From I-96 to the I-496/US- 127 Interchange CS JN

2 I-496/US-127 STUDY EXECUTIVE SUMMARY UNIVERSITY REGION MICHIGAN DEPARTMENT OF TRANSPORTATION This document includes the Executive Summary for the study, covering the overview, study area, congestion mapping, existing conditions, and alternatives analysis. The entire document is available for viewing by appointment. FOR MORE INFORMATION CONTACT: TRI-COUNTY REGIONAL PLANNING COMMISSION, JIM

3 Section 2: Executive Summary 2.1 Introduction This I-496/US-127 study was commissioned by the Michigan Department of Transportation (MDOT) to investigate existing and anticipated future conditions located in the cities of Lansing and East Lansing, Delhi and Lansing townships, Ingham County, Michigan. The findings of this planning level document are intended to be used as a guide for investment decisions and as a tool to help prioritize the need for future projects within the study area. The goal of this study is to evaluate the existing roadway and bridge conditions, existing and future traffic operations, and safety within the study corridor and develop a consistent strategy to provide safe and efficient movement of people and goods under existing and future conditions. 2.2 Study Area The initial focus of the proposed study area covered approximately 7.5 miles of I-496 and US-127 from College Road northerly to the westerly and northerly limits of the I-496/US-127/Trowbridge Road interchange area within the City of Lansing, City of East Lansing, Lansing Township, and Delhi Township, in Ingham County as shown in the exhibit below. Exhibit 2-1: Project Location US-127 Trowbridge Road Interchange I-496 I-496/US-127 Dunckel Road Interchange I-96 I-96 Interchange US-127 College Rd I-496 is a circumferential auxiliary highway of I-96 which extends from the west side of the city of Lansing, passes along the south side of the downtown business district, and then joins US-127 as a dual route running north/south reconnecting to I-96 on the southeast side of the city. There are 3 interchanges within the study limits: The I-496/US-127/I-96 interchange on the south end, Dunckel Road interchange which is approximately 1-mile north of I-96 and the I-496/US- 127/Trowbridge Road interchange at the northerly limits of the study area. Page 2-1

4 2.3 AM and PM Congestion Mapping Based on field observations and congestion scans using the Regional Integrated Transportation Information Software (RITIS) that archives vehicle speeds and travel time along the corridor, it was observed that typical commuting traffic heading northbound in the morning and southbound in the afternoon experiences recurring congestion. Exhibit 2-2: RITIS AM Congestion Mapping AM Peak: Figure 2-2 illustrates the average travel speed during the AM rush hour and the recurring congestion along northbound I-496/US-127. The most severe congestion is caused by the merge of the Dunckel Road entrance ramp traffic with a near capacity northbound I-496/US-127 mainline. The congestion from this merge area regularly spills back through the I-96/I- 496/US-127 system interchange. Northbound I-496/US-127 traffic also experiences a slowdown from the Dunckel Road entrance ramp merge to the US-127 and I-496 split north of Trowbridge Road. This slowdown is caused by lane changing and driver decision time at the I-496/US-127 Interchange. Exhibit 2-3: RITIS PM Congestion Mapping PM Peak: Figure 2-3 illustrates the regular congestion that occurs in the eastbound/southbound direction during the afternoon commuter rush. This congestion is due to limited capacity and multiple lane drops on EB I-496. The congestion begins in the afternoon peak at the left-hand lane drop along southbound I-496/US-127 immediately north of the Mt. Hope Avenue Bridge. The congestion spills back and creates stop and go conditions for EB I-496. This congestion is further exacerbated along eastbound I-496 by two consecutive lane drops prior to the merge with southbound US-127. Southbound US- 127 is also impacted by this congestion where the two mainline freeways merge together. Page 2-2

5 2.4 Existing Conditions Overview Based on review of old plans, survey information and field observations, an existing conditions overview is detailed below. Additional details with regard to the analysis of the existing geometry within the proposed project limits is included in Sections 3 and Roadway Cross Sections Within the study limits I-496/US-127 is an existing 4-lane freeway with an open ditch median and flush shoulders. The median width is generally 70 feet from north of Jolly Road to the CN Railroad just south of Trowbridge Road. North and south of those limits the median widens out through the Trowbridge interchange and I-96 interchange, respectively. The existing Right-of-Way (ROW) along the corridor is generally 300 feet in width and then widens out at each interchange area. There is a westbound/ northbound auxiliary lane that originates where the ramp from WB I-96 joins WB I-496/NB US-127 and extends to the WB I-496/NB US-127 exit loop ramp to Dunckel Road. There are also auxiliary lanes along NB US-127 between the Trowbridge and Kalamazoo Street interchanges. On EB I-496/SB US-127 between I-96 and Dunckel road there are 3 lanes. The Dunckel Road entrance ramp to EB I-496/SB US-127 adds an outside lane which then continues on as the outside lane on SB US-127 south of I-96. The median side lane of EB I- 496/SB US-127 drops at the exit ramp to EB I-96. Near the north end of the study area, at the merging area of EB I- 496 and SB US-127, there is a median side lane drop on EB I-496 approaching the merge and a median side lane drop on SB US-127 following the merge area, south of the CN Railroad. Ramps at the I-96, Dunckel Road, and Trowbridge Road interchanges generally consist of one 16-foot travel lane with flush shoulders. The EB I-496/SB US- 127 exit ramp to EB I-96 consists of two 12-foot lanes with flush shoulders Roadway Pavement Section Travel lanes on I-496/US-127 between I-96 and the south end of the mainline bridges over the CN Railroad consist of 2 to 7½ inches of hot mix asphalt (HMA) over 9-inches of jointed reinforced concrete pavement, 4 inches of aggregate base and 10 inches of sand subbase. The concrete pavement was originally constructed in 1964 and was most recently resurfaced with HMA in The shoulders in this section consist of 5 to 8 inches of HMA over aggregate base. The existing pavement is exhibiting high severity transverse and longitudinal joint reflective cracking with some areas exhibiting apparent failures in the underlying concrete pavement (see Exhibit 2-4). Exhibit 2-4: Existing Pavement Conditions (EB I- 496 / SB US-127 North of Forest Road) From the railroad bridges to the westerly limits along I-496 the existing pavement section consists of 10 inches of jointed reinforced concrete pavement, 4 inches of open-graded drainage course and 10 inches of sand subbase (reconstructed in 2001). Shoulders in this area consists of 5 inches of HMA over aggregate. The existing pavement is exhibiting low to moderate transverse and longitudinal joint spalling, but in general appears to be in good condition. A 1,600-foot WB/NB portion of this segment, from the south Exhibit 2-5: High Friction Surface Course on WB I-496 / NB US-127 North of Trowbridge Road end of the bridge over the CN RR to approximately 1,000 feet north of Trowbridge Road has an existing high friction surface course. The friction course is deteriorating and delaminating from the underlying concrete surface (see Exhibit 2-5). From the I-496/US-127 junction to the northerly limits along US-127 the existing pavement consists of 9 inches of jointed reinforced concrete, 4 inches of aggregate base and 10 inches of sand subbase (constructed in 1964). Existing shoulders in this section are HMA over aggregate. The pavement is in poor condition with areas of severe transverse Page 2-3

6 joint deterioration, mid-panel cracking and surface spalling. Nearly all of the original transverse joints have been previously repaired with full depth concrete repairs. The existing ramps at the Trowbridge Road interchange and the Dunckel Road interchange consist of 9 inches of jointed reinforced concrete pavement over 4 inches of aggregate base and 10 inches of sand subbase (constructed in 1964). Portions of the EB I-496/SB US-127 exit ramp to Dunckel Road were reconstructed in 2009 with an HMA over aggregate pavement section. Also, portions of the Dunckel Road ramps near the gores and along the tapers adjacent to the freeway have been overlaid with HMA. The concrete pavement portions of the ramps are in poor condition with areas of severe transverse joint deterioration, midpanel cracking, and surface spalling. Most of the original transverse joints have been previously repaired with full depth concrete repairs. The existing ramps at the I-96 interchange consist of variable thickness HMA over 9 inches of jointed reinforced concrete pavement over 4 inches of aggregate base and 10 inches of sand subbase (constructed in 1964). The pavement condition along these ramps is similar to the I-496/US-127 mainline pavement between I-96 and the CN Railroad Bridges The existing bridges located within the limits of this project were evaluated in their current state. Condition ratings in the current National Bridge Inspection Standards (NBIS) were confirmed in the field during the scoping inspections performed in 2016 (see Table 2-1 for a summary of these ratings). The bridges along I-496/US127 were constructed in the 1960 s, some of which have since been reconstructed. For bridges that were not reconstructed, various rehabilitation has been performed including overlays, widening and barrier replacements. Table 2-1: Current NBIS Conditions Ratings Summary for I-496 / US A Feature Feature Item 58 Bridge ID Deck Surface Carried Crossed Deck Exhibit 2-6: Ramp Condition (WB Trowbridge Rd Entrance Ramp to WB I-496) Item 59 Stringer Item 60 Abut Item 60 Pier R03 of EB I-496 CSX RR R05 of EB I-496 CN RR S10-3 of EB I-496 Mt. Hope Rd S09-3 of EB I-496 Forest Rd S12 of EB I-496 Jolly Rd S15 of Dunckel Rd. EB/WB I R04 of WB I-496 CSX RR R06 of WB I-496 CN RR R07 of WB I-496 Trowbridge Exit Ramp Rd. & CSX S10-4 of WB I-496 Mt. Hope Rd S09-4 of WB I-496 Forest Rd S14 of WB I-496 Jolly Rd S13 of US-127 NB I-96 WB Ramp S14 0f US-127 NB I-96 WB / 1997 S02 of US-127 NB I-96 EB / 1997 NBIS Condition Rating Scale: 9 = New, 7-8 = Good, 5-6 = Fair, 3-4 = Poor, 2 or less = critical. Year Built Page 2-4

7 2.4.4 Horizontal Alignment Five (5) horizontal curves on mainline I-496 / US-127 do not meet minimum radius requirements as noted in Table 2-2. Table 2-2: Mainline I-496/US-127 Horizontal Alignment Compliance Ex / (Min) Radius Location 1 (ft) WB I-496 / NB US-127 near Trowbridge Road P.I. Sta Curve NB 7 EB I-496 / SB US-127 near Trowbridge Road P.I. Sta Curve SB 6 SB US-127 merging area at EB I-496 P.I. Sta Curve SB 7 NB US-127 at Red Cedar River P.I. Sta Curve NB 8 SB US-127 at Red Cedar River P.I. Sta Curve SB 8 1 Minimum radius for a 75 mph design speed. 2 See Section 6 for crash analysis and proposed mitigations for this crash concentration Existing Design Speed Crash Concentration Noted? 1, (2,344) 60 mph No 1, (2,344) 65 mph Yes 2 1, (2,344) 65 mph Yes 2 1, (2,344) 60 mph Yes 2 1, (2,344) 65 mph Yes 2 Four (4) loop ramp curves have radii of 230 ft, which is less than the desired 260 ft minimum as follows: (1) NB US- 127 loop ramp to WB I-96; (2) WB I-96 loop ramp to SB US-127; (3) WB I-496/NB US-127 exit loop ramp to Dunckel Rd; and (4) WB Trowbridge Rd entrance loop ramp to EB I-496/SB US-127 Additionally, the WB I-496/NB US-127 exit ramp to EB Trowbridge Rd has a 230 ft radius, which is less than the required 464 ft minimum for a 40 mph design speed and the radius for the EB I-496/SB US-127 exit ramp to EB I-96 does not meet the minimum radius of 1,922 feet for a 70 mph curve, but does meet for a 65 mph design speed. All other mainline and ramp radii meet the minimum requirements for the desired design speeds Vertical Alignment The vertical alignment information used for the analyses was obtained from record plans and was noted that eight (8) mainline freeway crest vertical curves within the limits of proposed work do not meet minimum rate of curvature (Kvalue) requirements for a 75 mph design speed. Of the 8 mainline crest curves that do not meet the required K-value, five (5) meet K-value requirements for 70 mph, two (2) meet K-value requirements for 65 mph and one (1) meets the K-value requirements for 60 mph. Three (3) mainline freeway sag vertical curves within the limits of proposed work do not meet minimum rate of curvature (K-value) requirements for a 75 mph design speed. Of the 3 sag vertical curves that do not meet, two (2) meet the required K-value for a 65 mph design speed and one (1) meets the required K-value for a 50 mph design speed. One (1) ramp vertical curve (on the EB I-496/SB US-127 ramp to EB I-96) does not meet the K-value requirements for the desired ramp design speed of 70 mph, but does meet K-value requirements for 65 mph which exceeds the existing horizontal alignment design speed of 60 mph for this ramp. All mainline curves meet the minimum curve length criteria and all but one (1) ramp vertical curve within the limits of proposed work meet minimum curve length criteria; however, this is a short vertical curve approaching a stop condition at the ramp terminal on the EB I-496/SB US-127 exit ramp to Dunckel Rd. Page 2-5

8 2.4.6 Grade All mainline and ramp vertical grades, with the exception of one (2) locations, meet current geometric criteria: The vertical grade on SB US-127 between vertical curves SB-14 and SB-15 is a 3.11% up-grade, which exceeds the criteria of 3% maximum. The vertical grade on the WB I-496/NB US-127 exit ramp to EB Trowbridge Rd between vertical curves DD1 and DD2 is a 5% down-grade, which exceeds the criteria of 4% max Stopping Sight Distance Eight (8) mainline freeway crest vertical curves do not meet minimum SSD requirements for a 75 mph design speed. Of the eight (8) mainline crest curves that do not meet the required SSD, five (5) meet SSD requirements for 70 mph, two (2) meet SSD requirements for 65 mph and one (1) meets the SSD requirements for 60 mph. Three (3) mainline freeway sag vertical curves within the limits of proposed work do not meet minimum SSD requirements for a 75 mph design speed. Of the three (3) sag vertical curves that don t meet requirements, two (2) meet the required SSD for a 65 mph design speed and one (1) meets the required SSD for a 50 mph design speed. One (1) ramp vertical curve (on the EB I-496/SB US-127 ramp to EB I-96) does not meet the SSD requirements for the desired ramp design speed of 70 mph, but does meet vertical SSD requirements for 65 mph. In addition to vertical sight distances, horizontal sightline offsets were calculated to determine if stopping sight distance requirements were met for horizontal curves. Seven (7) locations were identified as having obstructions that inhibit the SSD as noted in Section 3 (Existing Conditions) Cross Slope The existing I-496/US-127 mainline cross slope on the through lanes is 1.5% - 2.0%, with the crown point located at the right edge of the median lane on each bound. Shoulder cross slopes are 4.0%. Old plan information shows ramp lane cross slopes at 1.5%, with the crown point located at the left edge of pavement. Ramp shoulder cross slopes are shown at 4.0% Superelevation Twelve (12) mainline freeway curves within the limits of proposed work do not meet the required rate of superelevation for the design speed (per Standard Plan R-107). Of these 12 curves, eight (8) meet the required rate of superelevation per the Straight Line Method; four (4) do not meet Straight Line. Two (2) ramp curves within the limits of proposed work do not meet the required rate of superelevation per Standard Plan R-107. One (1) of these 2 curves meets Straight Line requirements. Page 2-6

9 Vertical Clearance The existing vertical clearance for each structure within the proposed work limits along I-496 and US-127 is shown in Table 2-3. Table 2-3: Existing Bridge Vertical Clearance Structure Feature Being Crossed Roadway Over Approx. Station Existing Vertical Clearance Required Minimum & (Desired) Vertical Clearance Criteria Met? (Y/N) B01 of Red Cedar River and Ramp V EB I Y Y B02 of Red Cedar River and Ramp V WB I Y Y Exempted Bridge on Special Route? (Y/N) R03 of R04 of CSX RR EB I-496/SB US N - Trowbridge Rd (Ramps A, B, & F) EB I-496/SB US Y N CSX RR WB I-496/NB US Y - Trowbridge Rd (Ramps A, B, E & F) WB I-496/NB US Y N R05 of CN RR EB I-496/SB US Y - R06 of CN RR WB I-496/NB US Y - R07 of CSX RR WB I-496/NB US-127 Ramp to EB Trowbridge N - Rd S05 of SB US-127 Ramp to Trowbridge Rd EB I N N S06 of SB US-127 WB I Y - S09-3 of Mt. Hope Rd EB I-496/SB US (16-3 ) Y N S09-4 of Mt. Hope Rd WB I-496/NB US (16-3 ) Y N S10-3 of Forest Rd EB I-496/SB US (16-3 ) Y N S10-4 of Forest Rd WB I-496/NB US (16-3 ) Y N S12 of Jolly Rd EB I-496/SB US (16-3 ) N N S13 of EB I-496 Ramp to EB I-96 WB I-496/NB US (14-9 ) N Y* S14 of Jolly Rd WB I-496/NB US (16-3 ) N N S15 of WB I-496/NB US-127 Dunckel Rd (14-9 ) Y Y EB I-496/SB US-127 Dunckel Rd (14-9 ) Y Y S16 of SB US-127 Ramp to Trowbridge Rd WB I Y - B01 of Red Cedar River and Ramp V NB US Y Y* B02 of Red Cedar River and Ramp V SB US Y Y* *Not on MDOT s list of Exempt Bridges for Special Routes in Highly Urbanized Areas, but is over a ramp connecting a Special Route and a 16-0 Route. Vertical clearance sketches produced from Lidar scan data with detailed vertical clearance dimensions at each fascia are included at the end of Section 15. As shown in Table 2-3 six (6) existing structures within the limits of proposed work do not meet minimum vertical clearance requirements Horizontal Clearance A review of the project limits revealed that there are numerous objects such as bridge piers, slope paving, bridge abutments, railings, and overhead sign foundations, that are within the clear recovery area, and are currently protected by crashworthy barriers. Page 2-7

10 Ramp Acceleration and Deceleration Length Existing ramp geometry throughout the project was evaluated based on the MDOT Geometric Guides. Two (2) of the six (6) freeway entrance ramps within the proposed work limits do not meet the required L a distance. Four (4) out of eight (8) exit ramps within the proposed work limits do not meet the required L d distance Crash Analysis A crash analysis was completed for this project for a five-year period between 2011 and 2015, inclusive. The limits of this analysis include the mainline segments of I-496/US-127, system interchange ramps, and Trowbridge interchange ramps, from Trowbridge Road to I-96. This section of freeway experiences (on average) one crash every 1.75 days. The most frequent crash types for the mainline freeway segments were single vehicle (44%) and rear-end (37%) collisions. The leading crash types for the study interchange ramps were also single vehicle (70%) and rear-end (17%) crashes. The comprehensive crash report can be found in Section 6. On I-496 / US-127, crash concentrations were identified on the mainline S-curves through the Trowbridge interchange. These crashes predominantly involved vehicles losing control in the curves when surface friction was reduced, where 65%-80% of single vehicle and sideswipe crashes occurred in wet, snowy, icy, or slush road conditions. There was also a pattern of rear-end crashes on I-496 WB / US-127 NB from I-96 to Dunckel Road, and within the Trowbridge interchange, where 80% of the rear end collisions occurred during peak traffic conditions and recurring congestion. As described above, AM peak period congestion regularly spills back from Dunckel Road through the I-96/I-496/US- 127 system interchange. Crash concentrations can also be seen on I-96 related to this congestion, with westbound crash clusters (rear end specifically) at College Road and Hagadorn Road. A crash cluster related to peak period congestion is also observed on the ramp from I-496 EB to US-127 NB. Other mainline segments and ramps were not identified to experience specific crash clusters related to congestion; however, building congestion identified in the analysis of future no-build conditions could exacerbate crash patterns or cause new spot concentrations to develop. 2.5 Alternatives Studied Based on extensive study of the Existing and Base Future Conditions in addition to the geometric conditions, nine (9) build alternatives have been developed. Based on the findings outlined in the Existing Conditions Analysis Section of this Study, including safety elements, traffic operations, bridge conditions, geometrics, etc., alternatives were identified (as shown in Table 2-4) and preliminary traffic operations were reviewed to determine if the specific alternative should be moved forward for further study. Based on this preliminary analysis, the Preliminary Alternatives Analysis Meeting held on 06/30/2016 and the Preliminary Scope Review Meeting held on 08/26/16, six (6) of the nine (9) alternatives were proposed to move forward in addition to the Northbound and Southbound No-Build Alternatives. The six (6) alternatives as well as the no-build alternatives that were proposed to move forward for more in-depth review are as noted in Table 2-4 and as shown in Exhibits 2-7 through It should be noted that the alternatives as shown in the table on the following page have been broken up into Northbound Alternatives, Southbound Alternatives, and I-496/US-127 Interchange Realignment Alternatives. As presented, any of the Northbound and Southbound Alternatives could be combined with each other in order to form a merged alternative which addresses both the Northbound and Southbound operational, safety and geometric issues. Additionally, the I-496/US-127 Interchange Realignment Alternatives could also be combined with any of the Northbound and Southbound Alternatives to create a complete corridor fix. The I-496/US-127 Interchange Realignment Alternatives have been developed in order to understand what it might cost to modify the interchange configuration to meet current geometric standards as well as addressing the existing operational and safety issues. For overall work limit comparison purposes, the I-496/US-127 Interchange Realignment Alternatives incorporate the features of the Northbound and Southbound operational improvement Alternatives which include permanent lane additions (e.g. Northbound Alternative 4 and Southbound Alternative 5a). Page 2-8

11 Table 2-4: Proposed No-Build and Build Alternatives Treatment Extend NB Dunckel On-Ramp Acceleration Lane based on current MDOT/FHWA standards and traffic operation needs (widening to outside) Northbound Alternatives No- Build 3 1 1a 2 2a 3 3a 3b 3 3c 3d 4 2,3 4a 1 4b 1 X X X X X X X X X X X NB Dunckel On-Ramp to I-496/US-127 Metering X X X Extend 3 rd lane south from the I-496/US-127 split to meet current MDOT/FHWA standards (widening in median) X X X Part Time Shoulder Use from just north of the Jolly Road bridge (on NB US-127) to the I-496/US-127 split (north of the CSXT Railroad bridge) (widening in median) X X X X Part Time Shoulder Use from just north of the Jolly Road bridge (on NB US-127) to just south of the CN Railroad X bridge (widening in median) Permanent 3 rd Lane from Dunckel to I-496/US-127 split (widening in median) X X X Extend 4 th lane south from the I-496/US-127 split to meet current MDOT/FHWA standards (widening in median) X X Auxiliary Lane addition from the NB Dunckel On-Ramp to the EB Trowbridge Exit Ramp (widening to outside) 1 Alternative 4b is the same as 4a except MDOT would reclaim the existing (old) pavement width at the WB I-496 and NB US-127 split and put the lane lines back on the actual pavement joints. 2 Alternative 4 includes an option (add on) for an extension of the 4 th lane south from the I-496/US-127 split to meet current MDOT/FHWA standards with widening in the median. No-Build Alternative developed to compare against the build alternatives X Treatment Southbound Alternatives Interchange Realignment Alts No- Build 3 5 5a 3 6 6a 7 7a 7b 7c 3 7d Auxiliary Lane from the WB Trowbridge On-Ramp to EB I-496/SB US-127 to the Dunckel Exit Ramp (widening to outside), for Alternative 7c this would be a lane extension from the EB I-496 lane drop to Dunckel Exit Ramp Permanent lane addition from lane drop north of Mt. Hope Rd to approximately the Dunckel bridge over EB I- 496/SB US-127 (widening in median) with parallel extension of WB Trowbridge On-Ramp to EB I-496/SB US- 127 per current standards (widening to outside) Part Time Shoulder use from lane drop north of Mt. Hope Rd to I-96 (widening in median) X X X No-Build Alternative developed to compare against the build alternatives X X X Realign I-496/US-127 connections to I-496 and X US-127 (applies to Alternatives 8 and 9) Permanent upgrade of EB I-496/SB US-127 to EB I-96 exit X X New Mt. Hope Extension of the EB I nd thru lane (widening to outside) X X X X X Road Interchange Reconstruct/realign WB Trowbridge entrance loop ramp to EB I-496/SB US-127 due to extension of the EB I nd thru lane (widening to outside) Page 2-9 X X X X Remove the WB Trowbridge On-Ramp to EB I-496/SB US-127 X X Extend the median lane drop along EB I-496/SB US-127 south to just south of the Mt. Hope Road Bridge (widening in median) extended to a tangent segment of roadway 3 Graphical depictions of the alternatives selected to move forward for further study are included on the following pages. Color indicates alternatives to move forward in the study per the June 30, 2016 Progress Meeting. Color indicates alternatives not to move forward in the study per the June 30, 2016 Progress Meeting. Color indicates alternatives not to move forward in the study per the August 26, 2016 Preliminary Scope Review Meeting. X X Modified Trowbridge Rd Interchange Ramp Connections

12 Exhibit 2-7, Northbound No-Build Alternative (Detailed Map) Page 2-10

13 Exhibit 2-8, Alternative 3b (Detailed Map and Typical Cross Section) Page 2-11

14 Exhibit 2-9, Alternative 4 (Detailed Map and Typical Cross Section) Page 2-12

15 Exhibit 2-10, Southbound No-Build Alternative (Detailed Map) Page 2-13

16 Exhibit 2-11, Alternative 5a (Detailed Map and Typical Cross Section) Page 2-14

17 Exhibit 2-12, Alternative 7c (Detailed Map and Typical Cross Section) Page 2-15

18 Exhibit 2-13, Alternative 8 (Detailed Map) Page 2-16

19 Exhibit 2-14, Alternative 9 (Detailed Map) Page 2-17

20 Below is the reasoning for the alternatives which were not proposed to move forward in the study per the 06/30/2016 Progress Meeting and 08/26/16 Preliminary Scope Review Meeting with MDOT as shown in the table on the previous page (no additional costs or traffic information have been developed for these alternatives). 1 Alternatives eliminated as part of the 06/30/2016 Progress Meeting: Alternatives 1, 1a, 2 and 2a were eliminated as potential build alternatives as they did not alleviate existing traffic issues in the base and future year VISSIM models. As part of the VISSIM model development, it was determined that either a permanent third lane or Part Time Shoulder Use (PTS) lane in the peak hours was needed in order to alleviate the existing and future operational issues. Alternatives 3 and 3a were eliminated as potential build alternatives as the team determined that a permanent extension of the Northbound third lane at the WB I-496/NB US-127 split south of the rail bridges (widening in the median) should be included in the build alternatives. This permanent extension would be in use during peak and non-peak traffic periods and would upgrade the existing tapers to current standards. Alternatives 6 and 6a were eliminated as potential build alternatives as they did not alleviate existing traffic issues in the base and future year VISSIM models. Merging of the Westbound Trowbridge Road entrance ramp to EB I-496/SB US-127 was determined to be a significant issue as the alternatives were developed and traffic models developed and the accommodation of this issue was not addressed as part of these alternatives. Alternatives 7, 7a and 7d were eliminated as potential build alternatives as they did not alleviate existing traffic issues in the base and future year VISSIM models or meet the objectives of the study with regard to local agency considerations (i.e. Alternatives 7a and 7d required the removal of the WB Trowbridge entrance ramp). Alternatives eliminated as part of the 08/26/2016 Preliminary Scope Review Meeting: Alternative 3c was eliminated as a potential build alternative as the only difference between this alternative and Alternative 3b is proposed ramp metering on the NB Dunckel On-Ramp to WB I-496/NB US-127. As part of the VISSIM model development, it was determined that the ramp metering did not add additional capacity for WB I-496/NB US-127 and the metering actually queued traffic back onto Dunckel Road from the ramp. Alternative 3d was added for review during the meeting but was ultimately eliminated as a potential build alternative as it did not alleviate existing traffic issues in the base and future year VISSIM models. Based on review of the VISSIM model developed, this alternative pushed the bottleneck issue north from its current location near the Dunckel Road interchange to the Trowbridge Road interchange area. Alternatives 4a and 4b were eliminated as potential build alternatives as the team determined that a permanent extension of the 4 th lane south from the WB I-496/NB US-127 split to meet current MDOT/FHWA standards should be included in Alternative 4 as an option for future consideration. Based on development and review of the VISSIM model for Alternative 4, the extension of the 4 th lane is not required in order to alleviate existing traffic issues in the base and future year models. Additionally, the extension of this lane would require additional widening of the CN and CSXT rail bridges, increasing the cost of these alternatives. Alternative 5 was eliminated as a potential build alternative as the only difference between this alternative and Alternative 5a is the permanent lane addition occurs to the outside (Alternative 5 Auxiliary Lane addition from Trowbridge to Dunckel) while the Alternative 5a widening occurs to the median. The VISSIM model shows acceptable LOS for both alternatives, however the widening to the median is more cost effective. Alternative 7b was eliminated as a potential build alternative as it was shown in the base and future year VISSIM models that an operational improvement which extends beyond Dunckel Road is not necessary. Alternative 7c is proposed to be moved forward for further study which addresses many of the components of Alternative 7b with regard to EB I-496 lane balance fixes, but does not extend beyond Dunckel Road. Page 2-18

21 Northbound I-496 / US-127 Scoping SECTION 2 Executive Summary 2.6 Traffic Operations and Total Alternative Costs Future traffic operations were reviewed throughout the proposed work area to ensure that the design was able to accommodate future traffic volumes and could improve problem areas identified within the existing interchange and the future No- Build alternative. Tables 2-5, 2-6 and 2-7 give a brief summary of traffic operations for the Alternatives developed, the annual benefit in cost over a future No-Build alternative and a side-by-side comparison of anticipated impacts. Table 2-5: Traffic Operations Summary and Total Alternative Cost (Alternatives are highlighted as selected to move forward or eliminated as shown in this table and as detailed in Table 2-4) Alternative Description Annual Benefit* Total Estimated (Annual User Delay) Alternative Cost ** No-Build This alternative does not eliminate congestion on WB I-496/NB US-127. ($6,590,459) $50,707,000 Alternative 3b This alternative eliminated the congestion on northbound US-127/I-496 at the $4,131,450 $56,013,000 (Static) Dunckel on-ramp and improved operations near the US-127/I-496 split. ($2,459,009) $58,167,000 (Dynamic) Southbound Interchange Realignment Alternative 3c This alternative eliminated the congestion on northbound US-127/I-496 at the Dunckel on-ramp and improved operations near the US-127/I-496 split. $4,024,414 ($2,566,045) $60,125,000 (Full ATM) $56,125,000 (Static) $58,752,000 (Dynamic) $61,140,000 (Full ATM) Alternative 4 This alternative eliminated the congestion on northbound US-127/I-496 at the $4,237,262 $57,713,000 Dunckel on-ramp and improved operations near the US-127/I-496 split. ($2,353,197) Alternatives 4a and 4b This alternative eliminated the congestion on northbound US-127/I-496 at the Dunckel on-ramp and improved operations near the US-127/I-496 split. $4,163,477 ($2,426,982) $68,273,000 (4a) $67,597,000 (4b) No-Build This alternative does not eliminate congestion on EB I-496/SB US-127. ($10,259,887) $44,370,000 Alternative 5 This alternative eliminated the congestion on southbound US-127/I-496 although $8,567,675 $50,247,000 small amounts of congestion still remains on eastbound I-496 at the ($1,692,212) lane drop between the Trowbridge ramps. Alternative 5A This alternative eliminated the congestion on southbound US-127/I-496 although small amounts of congestion still remains on eastbound I-496 at the lane drop between the Trowbridge ramps. $8,563,887 ($1,696,000) Alternative 7B This alternative eliminated the congestion on southbound US-127/I-496. $8,629,203 ($1,630,684) Alternative 7C This alternative eliminated the congestion on southbound US-127/I-496. $8,594,925 ($1,664,962) Alternative 8 The analysis of future conditions with a new interchange at Mt. Hope Road Not indicates network operations similar to the other alternatives that have been Calculated moved forward for further study. Mainline traffic speeds would average between 50 and 65 miles per hour, with slight speed reductions at the system interchange (40 to 45 mph). Overall, traffic operations would be improved as compared to existing and future no-build conditions. Alternative 9 The analysis of future conditions with reconfiguration of the Trowbridge Road interchange indicates network operations similar to the other alternatives that have been moved forward for further study. Mainline traffic speeds would average between 60 and 70 miles per hour. Overall, traffic operations would be improved as compared to existing and future no-build conditions. Not Calculated $48,187,000 $56,784,000 (Static) $59,291,000 (Dynamic) $62,255,000 (Full ATM) $54,671,000 $238,247,000 $260,307,000 * Annual benefit based on user delay cost savings relative to a future No-Build alternative. ** See the following page with regard to details/definition with regard to the system components (i.e. Static, Dynamic, Full ATM). Page 2-19

22 Table 2-6: System Component Detail for Part Time Shoulder Use Alternatives Static PTS Dynamic PTS System Component Alternative Alternative Full ATM PTS Alternative Hours of Operation Fixed Variable to Conditions Variable to Conditions Capital Cost Lowest Highest Maintenance Cost Lowest Moderate Highest Available for Incident Management Available for Event Management Able to have queue warning and variable speed limits No Partial- PTS only Yes- For all Lanes Only if during normal hours of operation Yes Yes No No Yes Page 2-20

23 Table 2-7: Side by Side Comparison of Alternatives METRIC No-Build Alternative (Northbound) Alternative 3b (Northbound) Alternative 4 (Northbound) No-Build Alternative (Southbound) Alternative 5a (Southbound) Alternative 7c (Southbound) Alternative 8 (Interchange Realignment) Alternative 9 (Interchange Realignment) Operational Improvements Crash Analysis Review Does not improve current or future operational issues Eliminates congestion on northbound US-127/I-496 at the Dunckel on-ramp and improved operations near the US-127/I-496 split Crash concentrations were identified as follows: along the mainline S-curves through the Trowbridge interchange (loss of control due to weather and speed) and rear-end crashes on the mainline from I-96 northerly to the Dunckel Road interchange (due to traffic congestion) No improvement anticipated for the I-96 to Dunckel Road crash pattern High friction surface to be reapplied through the S-curve, horizontal curves will not be upgraded to current standards These alternatives eliminate congestion on northbound US-127/I-496, therefore it is anticipated that this will help in alleviating the existing crash pattern from I-96 to Dunckel Road High friction surface to be reapplied through the S- curve, horizontal curves will not be upgraded to current standards Does not improve current or future operational issues Eliminates congestion on southbound US-127/I- 496, some congestion still remains on EB I-496 at the lane drop between the Trowbridge ramps Eliminates the congestion on southbound US- 127/I-496 Crash concentrations were identified along the mainline S-curve through the Trowbridge interchange due to vehicles losing control in the curves when surface friction was reduced in inclement weather conditions Placement of a high friction surface treatment along with advanced curve warning signs with reduced speed are recommended (similar to what was completed along the WB I-496/NB US-127 S-curves through the Trowbridge interchange area) Eliminates congestion on northbound and southbound US-127/I-496 throughout the project limits Crash concentrations were identified as follows: along the mainline S-curves (NB & SB) through the Trowbridge interchange (loss of control due to weather and speed) and rear-end crashes on the mainline from I-96 northerly to the Dunckel Road interchange (due to traffic congestion) These alternatives eliminate congestion on NB US-127/I-496, therefore it is anticipated that this will help in alleviating the existing crash pattern from I-96 to Dunckel Modifications of the horizontal curves through the Trowbridge interchange are proposed which will eliminate the substandard geometrics and help in alleviating the existing crash pattern through the S-curves Design Exceptions Drainage Pavement Fix and Service Life Bridge Fix Environmental (wetlands, floodplain, etc.) Right-of-Way (ROW) Impacts Utility Impacts Railroad Impacts Minor roadway and bridge widening will increase the impervious area requiring additional retention (MS4 requirements) Rubblize with HMA Resurfacing (14-year service life) Minimal bridge widening for MOT and ramp geometrics Bridge replacement/rehab based on condition NPDES Permitting required along with tree removals Drainage easement for retention ITS Facilities and utilities (i.e. fiber optics) running along the railroads for bridge replacement Significant coordination with the CSXT & CN Railroads for bridge replacements Anticipate 1 to 2 years of coordination after Preliminary Plans are developed Significant roadway and bridge widening from I-96 through the I-496/US-127 interchange will increase the impervious area requiring additional retention based on MS4 requirements HMA Mill and Overlay (9-year service life) Rubblize with HMA Resurfacing (14-year service life) Significant bridge widening for new Part Time Shoulder Use and/or permanent lane additions and geometric modifications Bridge replacement/rehab based on condition NPDES Permitting required, wetland along with stream and floodplain impacts to the unnamed tributary of the Red Cedar River and its flood plains crossing the freeway south of Mt. Hope Road Additionally, tree removals will be required CSXT & CN Railroad ROW acquisition (easements) Drainage easement for retention ITS Facilities and utilities (i.e. fiber optics) running along the railroads for bridge replacement Relocation of Consumers Energy 46Kv line Realignment of the WB I-496/NB US-127 to EB Trowbridge Rd Ramp will require ROW acquisition (easements) from the CSXT & CN Railroads Anticipate 2 to 3 years of coordination after Preliminary Plans are developed Minor roadway and bridge widening will increase the impervious area requiring additional retention (MS4 requirements) Minimal bridge widening for MOT and ramp geometrics Bridge replacement/ rehab based on condition NPDES Permitting required along with tree removals Drainage easement for retention Significant roadway and bridge widening from I-96 through the I-496/US-127 interchange will increase the impervious area requiring additional retention based on MS4 requirements Rubblize with HMA Resurfacing (14-year service life) Rubblize with HMA Resurfacing (14-year service life) Significant bridge widening for permanent lane additions, lane balancing and geometric modifications Bridge replacement/rehab based on condition NPDES Permitting required, wetland along with stream and floodplain impacts to the unnamed tributary of the Red Cedar River and its flood plains crossing the freeway south of Mt. Hope Road Addition of a noise wall between Jolly and Dunckel Additionally, tree removals will be required CSXT & CN Railroad coordination Drainage easement for retention ITS Facilities and utilities (i.e. fiber optics) running along the railroads for bridge replacement Reconstruction and widening of the existing EB I-496/SB US-127 bridges over the CSXT & CN Railroads will require coordination and permitting Anticipate 1 to 2 years of coordination after Preliminary Plans are developed Significant roadway and bridge widening from I-96 through the I-496/US-127 interchange along with the reconfiguration of the Trowbridge interchange will increase the impervious area requiring additional retention based on MS4 requirements Pavement Recon in Interchange (26-year service life) Rubblize with HMA Resurfacing south to I-96 (14-year service life) Significant bridge replacement and reconfiguration within the I-496/US-127/Trowbridge interchange area due to the proposed geometric modifications Bridge replacement/rehab based on condition south of the I-496/US-127/Trowbridge interchange area NPDES Permitting required, wetland along with stream and floodplain impacts to the unnamed tributary of the Red Cedar River and its flood plains crossing the freeway south of Mt. Hope Road Addition of a noise wall between Jolly and Dunckel Additionally, tree removals will be required CSXT & CN Railroad ROW acquisition (easements) Drainage easement for retention Significant utility impacts are anticipated: Relocation of Consumers Energy 46Kv line; an in-depth review of the East Lansing waste water plant will be needed; AT&T, Comcast, Consumers, METC, etc. will all be reviewed in-depth Realignment of bridges within the I-496/US-127/Trowbridge interchange will require ROW acquisition (easements) from the CSXT & CN Railroads Anticipate 2 to 3 years of coordination after Preliminary Plans are developed Page 2-21

24 The findings of this study are considered conceptual and not final. Please note that a preferred alternative(s) has not been selected to date. Advancing specific alternative recommendations may require development of an environmental study and the appropriate environmental clearance approval. Additional examination of the proposed alternatives may be required throughout the environmental review process and design phase. To implement the proposed improvements identified in this study, some combination of available federal, state and local public and private funding sources would need to be leveraged when funding becomes available and construction schedules are determined. Page 2-22