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SunTrust Park Area Transportation Improvement Study

January 2015

SunTrust Park Area Transportation Improvement Study Prepared for:

Cobb County DOT

Prepared by:

ARCADIS U.S., Inc.

2410 Paces Ferry Road

#400

Atlanta

Georgia 30339

Tel 770 431 8666

Fax 770 435 2666

Our Ref.:

GA064005.1406

Date:

January 2015

This document is intended only for the use

of the individual or entity for which it was

prepared and may contain information that

is privileged, confidential and exempt from

disclosure under applicable law. Any

dissemination, distribution or copying of

this document is strictly prohibited.

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Table of Contents

1. Introduction 4

1.1 Purpose of the Analysis 4

1.2 Study Area 4

1.3 Report Organization 6

2. Data Collection and Analysis Methodology 7

2.1 Data Sources 7

2.2 Methodology 7

3. Existing Conditions (2014) 8

3.1 Existing Conditions Volume Diagrams 8

3.2 Intersection Capacity Analysis Summary 11

3.3 Operational Issues Summary 13

4. Review of Existing Plans and Programmed Projects 13

5. Review of DRI 2381 (Atlanta Braves Stadium and Mixed-Use Development) 16

6. Future Conditions Analysis (2019) 17

6.1 Baseline Intersection Capacity Analysis 17

6.2 No-Build Intersection Capacity Analysis 19

7. Proposed Improvements 22

7.1 Proposed Improvements and Benefit/Cost Analysis 22

7.2 Intersection and Arterial Capacity Analysis Summary (With Improvements) 34

7.3 Prioritization Methodology and Scheduling of Proposed Improvements 36

7.3.1 Study Goals and Objectives 36

7.3.2 Prioritization Methodology 37

7.4 Prioritization 38

8. Funding 40

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Table of Contents

Tables

Table 1 Existing Conditions Delay (sec/veh) and LOS 12

Table 2 Planned and Programmed Projects 14

Table 3 Baseline Intersection Delay (sec/veh) and LOS 17

Table 4 No-Build Intersection Delay (sec/veh) and LOS 19

Table 5 Estimated Costs for Cobb-A 24

Table 6 Estimated Benefits for Cobb-A 24

Table 7 Estimated Costs for Cobb-B 25

Table 8 Estimated Benefits for Cobb-B 25

Table 9 Estimated Costs for Cobb-C 26

Table 10 Estimated Benefits for Cobb-C 26

Table 11 Estimated Costs for Cobb-D 27

Table 12 Estimated Benefits for Cobb-D 27

Table 13 Estimated Costs for Cobb-E 28

Table 14 Estimated Costs for Cobb-1 29

Table 15 Estimated Costs for Cobb-2 30

Table 16 Estimated Costs for DRI-A 31

Table 17 Estimated Benefits for DRI-A 31

Table 18 Estimated Costs for DRI-B 32

Table 19 Estimated Benefits for DRI-B 32

Table 20 Estimated Costs for DRI-C 33

Table 21 Build Intersection Delay (sec/veh) and LOS 34

Table 22 Project Prioritization 39

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Table of Contents

Figures

Figure 1 Study Area 5

Figure 2 AM Queueing Map 9

Figure 3 PM Queueing Map 10

Figure 4 Level of Service (LOS) 11

Figure 5 Proposed Project Locations 23

Appendices

A Traffic Volumes

B Synchro Results

C Concept Drawings

D Cost Estimates

E Project Sheets

F Financial Details and Project Funding

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1. Introduction

This study provides an analysis of traffic impacts associated with a proposed baseball stadium, to

be named SunTrust Park, and mixed use development in the northwest quadrant of the I-75 and I-285 interchange in Cobb County, Georgia. The planned development includes a new 45,000 seat stadium for the Atlanta Braves along with a mixed use development comprised of 630,000 square

feet of office, 500,000 square feet of retail, a 100,000 square foot multi-use facility, 600 residential dwelling units, and a 450 room hotel. All transportation improvements will be identified and evaluated based on forecasted year 2019 traffic conditions. By 2019, SunTrust Park and the

majority of the mixed-use development will be built out.

1.1 Purpose of the Analysis

This study will evaluate, rank, and recommend transportation projects to minimize impacts due to SunTrust Park and the proposed mixed use development surrounding the stadium. The proposed

improvements will assist in efficient movements of daily and game-day traffic along with the current heavy commuter traffic which exists in the area. A prioritized list of improvements will be the final result of the study.

1.2 Study Area

A review of key access routes and the roadway network in the vicinity of the proposed development was the basis for determining the study area boundaries. The study area is roughly bounded by Windy Hill Road to the north, Terrell Mill Road, Powers Ferry Road, and Cumberland Parkway to the

east, Akers Mill Road and Cumberland Parkway to the south, and Cumberland Parkway and US 41 (Cobb Parkway) to the west. Figure 1 shows the study area, the nine intersections that will be analyzed as part of this study, and the intersections that were previously studied by the developer.

Figure 1: Study AreaLegend

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1.3 Report Organization

This report is divided into the following sections:

Data Collection and Review: Provides an overview of data sources and methodologies

used to perform the traffic analysis.

Existing Conditions (2014): develop and calibrate a traffic simulation model to reflect 2014 existing conditions. This section includes summaries of operational issues and system level

performance.

Review of Existing Plans and Programmed Projects: discussion of roadway projects as well as major developments in the pipeline within the study area between 2014 and 2020.

DRI Review: Comments on the methodology, findings, and proposed improvements presented in DRI 2381 (Atlanta Braves Stadium and Mixed-Use Development) are included in this section.

Future Baseline Conditions Analysis (2019): develop and calibrate a traffic simulation model to reflect 2019 baseline conditions. The model will include the current roadway configuration and all committed transportation projects that will be in place by 2019. This section includes

summaries of operational issues and system level performance.

Proposed Improvements: Detailed traffic analysis of various improvement scenarios identified and evaluated to improve traffic operations in the study area. This section also

includes a list of the preferred transportation improvements in the study area to accommodate traffic from the proposed developments.

Transportation Improvements Schematics and Costing: This section includes planning level

conceptual schematics for improvements identified through the traffic analysis. Planning level conceptual cost estimates for preliminary engineering, right of way, and construction for each project are also included.

Future Build Conditions Analysis (2019): develop and calibrate a traffic simulation model to reflect 2019 build conditions. The model will include the current roadway configuration and all committed transportation projects that will be in place by 2019 as well as new

connections, access roads, and driveways to reflect the build scenario. This section includes summaries of operational issues and system level performance.

Project Prioritization: This section ranks the proposed improvements based on criteria such

as overall benefit, ease of implementation, proximity to the development site, and applicability to multiple transportation modes. Additionally, an overview of the current

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transportation funding environment and potential funding sources are included.

2. Data Collection and Analysis Methodology

Land use and traffic data was collected from various sources for this study. Land use data collected was associated with DRI 2381 (Atlanta Braves Stadium and Mixed-Use Development) and included

the type and size of development, site plan, and driveway locations. Traffic data for the study included existing traffic counts, roadway and intersection geometry, signal phasing, and posted speed limits. Open year forecasted driveway volumes from DRI 2381 (Atlanta Braves Stadium and

Mixed-Use Development) are also used in this study.

2.1 Data Sources

The following data sources were used for this study:

Traffic Volume Counts: Traffic counts were collected by a traffic vendor during the AM and PM peak hours.

SCATS: Due to the counts being collected near the end of the school year, traffic count data was compared to approach volumes from the Cobb County’s adaptive signal system, SCATS.

Field Reviews: Existing roadway and intersection geometry, signal phasing, and posted speed limits were collected by ARCADIS personnel.

DRI 2381 (Atlanta Braves Stadium and Mixed-Use Development): Intersection traffic counts for intersections evaluated by the DRI and forecasted open year volumes (including

driveway volumes) were obtained from the DRI.

2.2 Methodology

The data obtained was used to develop and calibrate a traffic simulation model using Synchro 8 to reflect existing 2014 AM and PM weekday peak hour conditions. Two sets of traffic volumes, with

and without site traffic, were developed for 2019. These were developed using a one percent annual growth rate and utilizing site generated traffic and routing outlined in the DRI. The growth rate assumptions were utilized to be consistent with the DRI but were also validated based on historical

counts in the study area.

With SunTrust Park construction scheduled to be complete in 2017, the analysis year of 2019 was

chosen to allow for sufficient time for development of adjacent, mixed-use facilities. Additionally,

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2019 aligns with the analysis year used in the DRI. Three scenarios were modeled for 2019 and each scenario is described below:

Baseline: This scenario was completed to provide a baseline of the conditions in the study area. For this scenario, the assumption was made that SunTrust Park was not constructed and volumes would be existing volumes plus a one percent annual growth rate.

No-Build: This scenario assumes that SunTrust Park is constructed but no improvements are made to intersections. Volumes for this scenario are baseline volumes plus SunTrust

Park site traffic obtained from the distributions used in the DRI. The purpose of this scenario is to determine the direct impact of SunTrust Park and associated development traffic to the study intersections.

Build: This scenario evaluated improvements to intersections found deficient in the No-Build scenario. For the purposes of this study, deficient was defined as operating at LOS E or F,

and having an increase in delay over the baseline conditions.

Results from the existing 2014 and future 2019 traffic analysis were then used to identify

transportation needs within the study area. After needs identification, projects to improve mobility within the study area were identified. Finally, improvement scenarios were identified and evaluated to improve study area traffic operations.

3. Existing Conditions (2014)

3.1 Existing Conditions Volume Diagrams

Intersection turning movement counts were obtained for AM and PM peak periods. These counts were then analyzed to identify the peak hour for each intersection. Since traffic counts only provide engineers with the throughput at each intersection, field visits were completed to identify any

additional queuing which occurs at the study intersection. Figures 2 and 3 show the location and length of queues for the AM and PM peak hours respectively. These queues were then converted to number of vehicles using the assumption that each vehicle is approximately 25 feet long.

Existing year traffic volumes are available in Appendix A.

Figure 2: AM QueuingLegend


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3.2 Intersection Capacity Analysis Summary

The intersection capacity analysis was completed using Synchro 8. The analysis uses geometry

peak hour volumes and optimized signal timings to determine the intersection delay based on guidance provided by the Highway Capacity Manual (HCM). Intersection delay can be associated with a level of service (LOS) or a grade given to each intersection based on its operations. Similar to

typical school grading systems, intersections operating at LOS A are considered to be operating at the best conditions while those operating at LOS F are considered to be operating at the lowest conditions. Figure 4 illustrates LOS.

Figure 4: Level of Service (LOS)

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Intersections in urban areas are typically considered as operating at acceptable levels if they operate at LOS D or better. Many of the intersections in this study currently operate at acceptable LOS. Only two of the nine intersections studied operate at unacceptable LOS. The intersection of

Powers Ferry Road at Terrell Mill Road operates with the lowest LOS (LOS F) and with the highest delay of the intersections studied. Table 1 below shows the average delay per vehicle in seconds and the level of service for each study intersection for the existing AM and PM peak hours.

Table 1: Existing Conditions Delay (sec/veh) and LOS

Intersection AM Peak Hour PM Peak Hour

Northside Drive at New Northside Drive/Interstate N Parkway

22.4 (LOS C) 30.9 (LOS C)

Powers Ferry Road at Terrell Mill Road 90.4 (LOS F) 51.3 (LOS D)

Cumberland Parkway at Cumberland Boulevard

41.2 (LOS D) 52.7 (LOS D)

Powers Ferry Road at Akers Mill Road 40.7 (LOS D) 64.2 (LOS E)

Windy Ridge Parkway at Interstate N Parkway 21.1 (LOS C) 36.2 (LOS D)

Cobb Parkway at I-285 Eastbound Ramps 27.9 (LOS C) 30.7 (LOS C)

Cobb Parkway at I-285 Westbound Ramps 26.1 (LOS C) 34.9 (LOS C)

Cobb Parkway at Circle 75 Parkway/Spring

Road 47.6 (LOS D) 45.8 (LOS D)

Cobb Parkway at Windy Ridge Parkway 31.5 (LOS C) 44.2 (LOS D)

I-75 Northbound Ramps at Delk Road 12.9 (LOS B) 15.8 (LOS B)

I-75 Southbound Ramps at Delk Road 29.1 (LOS C) 24.3 (LOS C)

Terrell Mill Road at Delk Road 28.8 (LOS C) 31.7 (LOS C)

Powers Ferry Road at Delk Road 34.2 (LOS C) 60.1 (LOS D)

Windy Ridge Parkway at Interstate N Circle 21.6 (LOS C) 27.5 (LOS C)

Cumberland Boulevard at Akers Mill Road 11.7 (LOS B) 17.6 (LOS B)

Cumberland Boulevard at Spring Hill Parkway 11 (LOS B) 15 (LOS B)

Herodian Way at Circlecle 75 Parkway 4.6 (LOS A) 7.2 (LOS A)

Spring Road at Cumberland Boulevard 30.0 (LOS C) 58.2 (LOS E)

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3.3 Operational Issues Summary

As was previously stated, urban intersections operating at LOS D or better during both peak periods

are typically considered to be operating at acceptable LOS. For those intersections which operate at LOS E or F, additional analysis was completed to determine the specific movement or group of movements that are operating deficiently. The findings of that analysis are summarized below:

Powers Ferry and Terrell Mill Road

o AM peak hour the Terrell Mill Road eastbound approach has the longest delay of 108.5 sec/veh (LOS F) due to the large number of vehicles turning right. The eastbound right turning movement has a delay of 170.3 sec/veh.

o During the PM peak hour Terrell Mill Road eastbound and westbound through movements have delays of 101.8 and 102.0 sec/veh respectively. The northbound

and southbound left turning movements also have long delays of 105.2 and 123.8 sec/veh respectively.

Powers Ferry and Akers Mill Road

o PM peak hour the Akers Mill Road eastbound left turning movement has a delay of

180.7 sec/veh causing the eastbound approach to have the longest delay of 99.8 sec/veh (LOS F). The westbound through movement also has a long delay of 155.5 sec/veh giving the westbound approach an overall delay of 69.6 sec/veh (LOS E).

4. Review of Existing Plans and Programmed Projects

A variety of existing plans were reviewed to identify proposed infrastructure projects that may impact traffic in the study area. Planned and programmed projects with completion dates of 2019 or earlier

were included in the 2019 future conditions Synchro 8 modeling effort. Plans reviewed included Plan 2040 Regional Transportation Plan and the Transportation Improvement Plan, both by ARC, Cobb in Motion (the Cobb County Comprehensive Transportation Plan)1, and DRI 2381(Atlanta Braves

Stadium and Mixed-Use Development). Additionally, Cobb County staff provided input regarding projects currently in the works but not currently included in the above plans. Table 2 lists the projects within or adjacent to the study area that were identified.

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Table 2: Planned and Programmed Projects

Project Number

Location Improvement Proposed

Year

D11E0 US 41 (Cobb

Parkway) US 41 (Cobb Parkway) bridge replacement over the Chattahoochee River

Current

CO-041 US 41 (Cobb

Parkway)

This project is in a scoping phase to recommend potential improvements on US 41 (Cobb Parkway) between Windy Ridge and SR 120 Loop (North Marietta Parkway). Improvements may include a widening from 4 to 6 lanes, with completion expected in 2030.

2014

CO-381 Powers Ferry

Road Adding a northbound lane to Powers Ferry Road from Wildwood Parkway to Terrell Mill Road

TBD

CO-382 Windy Hill

Road

Widening westbound Windy Hill Road from two to three lanes between east of Powers Ferry Road and Spectrum Circle

2015

CO-453 US 41 (Cobb

Parkway) Cobb Community Tranist Route 10X Operating Assistance

2015

CO-380 Leland Drive New Location

Leland Drive Extension - New Alignment from Windy Hill Road to Terrell Mill Road

2016

CO-446 Bob Callan

Trail Bob Callan Trunk Trail Phase II - Section A 2016

CO-447 Bob Callan

Trail Bob Callan Trunk Trail Phase II - Section B 2016

CO-452 I-75 and

Windy Hill Road

Intallation of a Diverging Diamond Interchange (DDI) at the I-75 and Windy Hill Road interchange

2016

CO-454 Windy Hill

Road Windy Hill Road widening from US 41 to I-75 2016

CO-455 Windy Hill

Road Windy Hill Road improvements from Rottenwood Creek to Spectrum Circle/Interstate North Parkway

2016

E3030

US 41 (Cobb Parkway) and

Windy Hill Road

Intersection improvements at the SR 3/US 41 (Cobb Parkway) at Windy Hill Road intersection

2016

E4020 Windy Hill

Road

Windy Hill Road safety and traffic improvements between I-75 and US 41 (Cobb Parkway) - installation of a raised median and addition of one through lane in each direction

2016

E4030 Windy Hill

Road

Windy Hill Road safety and traffic improvements between I-75 and US 41 (Cobb Parkway) - installation of a raised median and addition of one through lane in each direction

2016

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Table 2: Planned and Programmed Projects

Project Number

Location Improvement Proposed

Year

AR-ML-930 I-75 and I-

575 Northwest Corridor (I-75 and I-575) Managed Lanes 2018

AR-409 A I-285 Right-of-way acquisition for the I-285 north corridor high capacity rail service

2030

CO-AR-238 I-75 Ten-lane collector/distributor system along I-75 from I-285 north to Delk Road as part of the reconstruction of the Windy Hill Road interchange

2030

AR-409A I-285 Revive 285 - I-285 North Corridor High Capacity Rail Service - Protective Right of Way Aquistion

LR 2031-2040

AR-475 US 41 (Cobb

Parkway)

Connect Cobb/Northwest Atlanta Transit Corridor construct dedicated transit guideway on US 41 (Cobb Parkway) from Kennesaw State University to the Cumberland Activity Center.

LR 2031 - 2040

AR-959 I-285 Revive 285 - I-75 North / I-285 Interchange Improvements at I-75 Northbound to I-285 Westbound flyover ramp

LR 2020-2030

AR-960 I-75 at I-285 Revive 285 - I-75 North / I-285 Interchange Improvements

LR 2020-2030

CO-AR-238 I-75 at I-285 Revive 285 - I-75 North / I-285 Interchange Upgrades LR 2031-

2040

ASP-AR-415 Northwest Corridor

Northwest Corridor high capacity rail service from the Beltline Corridor to the Cumberland/Galleria area

TBD

ASP-AR-416 Northwest Corridor

Northwest Corridor transit service from the Cumberland/Galleria area to Southern Polytechnic Institute

TBD

ASP-AR-ML 210

I-285 I-285 West Managed Lanes from I-20 west to I-75 North

TBD

ASP-CO-428 Windy Hill

Road Widening of Windy Hill Road from Austell Road to I-75 North

TBD

ASP-ML-200 I-285 I-285 North Managed Lanes and collector/distributor improvments from I-75 north to I-85 north

TBD

Projects CO-380, CO-381, CO-454, and ASP-CO-428 are recommended in Cobb in Motion.

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5. Review of DRI 2381 (Atlanta Braves Stadium and Mixed-Use Development)

ARCADIS completed an analysis of the Atlanta Braves Stadium and Mixed-Use Development DRI.

From this review yielded comments concerning the trip generation, traffic volumes, and the traffic analysis. The first observation was that a more detailed explanation of assumptions should be made. This could include additional documentation such as a mapping of the trip origin (through

ticket holder information) or graphical representation of turnstile data.

In regards to the trip generation, proposed shopping and dining options in the area surrounding SunTrust Park would expectedly result in fans arriving to the game early. This would likely result in a

more than 25 percent entering trip distribution during the peak hour found in the provided Turner Field data. Secondly, it is unclear whether additional time was added to the arrival distribution provided by Turner Field turnstile data to cover parking and walking to SunTrust Park. Current start

times are typically 7:10pm, with the distributed parking (proposed for the new site) patrons will need plenty of time to find parking and walk to SunTrust Park. It should be assumed that more traffic will arrive at SunTrust Park during the peak hours 5-6 pm. Furthermore, the assumption of 2.8 patrons

per vehicle for the Atlanta area should be confirmed if survey data is available. Lastly, attention should have been given to traffic departing after weekday afternoon games, while these games are limited, cities such as Cleveland, Ohio do experience gridlock when traffic exiting the stadium

interacts with PM peak hour traffic.

The assumption of one percent annual growth when concerning traffic volumes seems to be in line with GDOT historical count data within the study area. While the analysis traffic appears to be

consistent with traffic counts, the traffic volumes used in the traffic modeling appeared to be throughput volumes. For analysis purposes, volumes should include unserved traffic (queued vehicles). There was no mention about the handling of queues in the report.

Regarding the traffic analysis steps, it was unclear if the pedestrian traffic at site-adjacent intersections was considered. The pedestrian movements could have a significant impact on the intersection operations especially at intersections adjacent to the site. Based on the parking map

provided, approximately 55 percent of the traffic will park off-site. This will be approximately 4,000 vehicular trips or 11,200 patrons (based on the DRI assumptions). It is unclear in the report if pedestrian facilities exist to support this traffic and what impact the pedestrian traffic will have on

motorists at the signalized intersections. Lastly, existing conditions in Synchro appear to generally be better than expected for most intersections. Based on Table 7 in the DRI Traffic Study, the only intersection currently operating at a LOS F is Cobb Parkway at Windy Hill Road. Queueing occurs

on a daily basis along several corridors including Powers Ferry Road, Windy Hill Road east of I-75, and Cobb Parkway. For example, a study of the Windy Hill Road and I-75 interchange completed in December 2013 indicated that the intersections of Windy Hill Road and I-75 Northbound, and Windy

Hill Road at Leland Drive will operate at LOS F during the PM peak hour. This could be a result of intersection queues not being considered in the DRI.

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It is recommended that the County or developer complete an additional study to further identify operational deficiencies and potential pedestrian areas of impacts once parking locations are finalized. This additional analysis should also consider pre and post-game intersection operational

plans. Additionally, peak period, site generated traffic should probably be increased based on the additional time required for distributed parking.

6. Future Conditions Analysis (2019)

Regardless of the development of SunTrust Park and the proposed mixed-use facilities surrounding it, existing congestion at the study intersections and at other area intersections is expected to

continue to increase in severity as growth continues in the area. Three future year scenarios were analyzed to determine the deficiencies in 2019 with and without the project, as well as to propose improvements. A baseline analysis was completed to determine what conditions would be like

without the development to allow for a more accurate determination of the impacts due to the site traffic. The no-build analysis evaluated the intersection performance with the site traffic but without any improvements. The comparison of these two alternatives yields the impact of site traffic. The

final alternative was a build alternative which proposed improvements based on deficiencies identified in the no-build conditions. The following sections discuss the results of the analysis and the intersection deficiencies for each scenario.

6.1 Baseline Intersection Capacity Analysis

Using volumes, intersection geometry, and signal phasing, a Synchro 8 traffic model was developed to analyze intersection capacity and operations for each scenario. By 2019, three intersections are

expected to operate at unacceptable LOS. The average delay per vehicle in seconds and the level of service for the Baseline conditions are shown in Table 3 below.

Table 3: Baseline Intersection Delay (sec/veh) and LOS



25.7 (LOS C) 33.5 (LOS C)

Powers Ferry Road at Terrell Mill Road 101.3 (LOS F) 54.1 (LOS D)

Cumberland Parkway at Cumberland

Boulevard 42.5 (LOS D) 57.5 (LOS E)


Windy Ridge Parkway at Interstate N Parkway 21.7 (LOS C) 38 (LOS D)

Cobb Parkway at I-285 Eastbound Ramps 29.5 (LOS C) 31.1 (LOS C)

Cobb Parkway at I-285 Westbound Ramps 27.2 (LOS C) 37.2 (LOS D)

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Cobb Parkway at Circle 75 Parkway/Spring Road

53.6 (LOS D) 49.9 (LOS D)

Table 3 (Continued): Baseline Intersection Delay (sec/veh) and LOS


Cobb Parkway at Windy Ridge Parkway 32.4 (LOS C) 46.8 (LOS D)



Terrell Mill Road at Delk Road 31.5 (LOS C) 37.3 (LOS D)

Powers Ferry Road at Delk Road 35.4 (LOS D) 62.3 (LOS E)

Windy Ridge Pkwy at Interstate N Circle 23 (LOS C) 27.8 (LOS C)

Cumberland Boulevard at Akers Mill Road 11.9 (LOS B) 18.2 (LOS B)

Cumberland Boulevard at Spring Hill Parkway 10.8 (LOS B) 15.4 (LOS B)

Herodian Way at Circle 75 Parkway 4.7 (LOS A) 9 (LOS A)

Cumberland Boulevard at Spring Road 31.4 (LOS C) 67.9 (LOS E)

For the intersections operating at a level of service of E or F from the table above, further analysis was completed to determine which movement or approach was operating at or over capacity. The

findings of the analysis are shown below.

Powers Ferry & Terrell Mill Road

o AM peak hour Terrell Mill Road eastbound approach has the longest delay of 127.6 sec/veh (LOS F) due to the right turning movement which has a delay of 203.4 sec/veh.

Cumberland Pkwy & Cumberland Blvd

o PM peak hour, the Cumberland Parkway westbound approach has the longest

delay of 76.5 sec/veh (LOS E) due to the through movement with a delay of 91.7 sec/veh.

Powers Ferry & Akers Mill Road

o PM peak hour, the Akers Mill Road eastbound approach has the longest delay of 125 sec/veh (LOS F) due to the left turning movement which has a delay of 231.6

sec/veh.

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6.2 No-Build Intersection Capacity Analysis

As one would expect, without additional improvements at area intersections, the additional

development traffic will result in more congestion and higher delays. Without further improvement, 12 of the 18 intersections will operate at unacceptable LOS. Table 4 below shows the average delay per vehicle in seconds and the level of service for each study intersection for the no-build AM and

PM peak hours.

Table 4: No-Build Intersection Delay (sec/veh) and LOS

Intersection AM Peak hour PM Peak Hour


27.9 (LOS C) 96.2 (LOS F)

Powers Ferry Road at Terrell Mill Road 107.1 (LOS F) 56 (LOS E)


42.7 (LOS D) 58.2 (LOS E)

Powers Ferry Road at Akers Mill Road 46 (LOS D) 88.7 (LOS F)

Windy Ridge Parkway at Interstate N Parkway 28.5 (LOS C) 61.9 (LOS E)

Cobb Parkway at I-285 Eastbound Ramps 35.2 (LOS D) 69.4 (LOS E)

Cobb Parkway at I-285 Westbound Ramps 34.8 (LOS C) 98.7 (LOS F)


Road 159.1 (LOS F) 92.4 (LOS F)

Cobb Parkway at Windy Ridge Parkway 36.7 (LOS D) 60.6 (LOS E)



Terrell Mill Road at Delk Road 32.1 (LOS C) 38.3 (LOS D)

Powers Ferry Road at Delk Road 35.5 (LOS D) 62.5 (LOS E)

Windy Ridge Pkwy at Interstate N Circle 23 (LOS C) 28.6 (LOS C)

Cumberland Boulevard at Akers Mill Road 11.9 (LOS B) 20.3 (LOS C)

Cumberland Boulevard at Spring Hill Parkway 10.8 (LOS B) 12.3 (LOS B)

Herodian Way at Circle 75 Parkway 4.7 (LOS A) 527.8 (LOS F)

Cumberland Boulevard at Spring Road 31.3 (LOS C) 81.5 (LOS F)

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For the intersections operating at a LOS E or F from the table above, further analysis is done to determine which approach at the intersection is causing the most overall delay.

Northside Drive & New Northside Drive/Interstate N Parkway

o PM peak hour, the Northside Drive westbound through movement has the longest delay of 188.4 sec/veh which is the only movement operating at LOS D or worse. This movement has an overall delay of 155.3 sec/veh and the only

approach with a LOS F. This intersection changes from operating at LOS C with 33.5 sec/veh delay in baseline conditions to LOS F with a delay of 96.2 sec/veh in no-build conditions.

Cumberland Pkwy & Cumberland Blvd

o PM peak hour, the Cumberland Parkway westbound approach has the longest delay of 76.7 sec/veh (LOS E) due to the right turning movement with a delay of

91.9 sec/veh. The turning delay in an increase of less than a second over baseline conditions.

Powers Ferry and Terrell Mill Road

o AM peak hour Terrell Mill Road eastbound approach has the longest delay of 127.6 sec/veh (LOS F) mostly due to the right turning movement that has a delay of 203.4 sec/veh. This movement does not change from baseline to no-build

counts. However, the northbound left movement delay increases significantly from 165.9 sec/veh in baseline conditions to 186.9 sec/veh in no-build conditions.

o PM peak hour Terrell Mill Road eastbound and westbound approaches would

reach (LOS F) with westbound having the longest delay of 107.5 sec/veh mostly due to the westbound through movement with a delay of 112.7 sec/veh. This movement increases by six sec/veh from baseline to no-build conditions.

Windy Ridge Pkwy & Interstate N Pkwy

o PM peak hour the Windy Ridge Parkway westbound approach has the longest delay of 75.1 sec/veh (LOS E) due to the through movement with a delay of 85.9

sec/veh. This movement increased from 52.2 sec/veh in baseline conditions to 85.9 sec/veh in no-build conditions.

21

Cobb Pkwy & I-285 Eastbound Ramps

o PM peak hour, the I-285 Eastbound Off-ramp has the longest delay of 152.2 sec/veh (LOS F). The left and right turning movements have delays of 152.5

sec/veh and 151.7 sec/veh, both contributing to the delay of that approach. The delay at this intersection more than doubles from baseline conditions to no-build conditions.

Cobb Pkwy & Circle 75 Pkwy/Spring Road

o AM peak hour Spring Road eastbound approach has the longest delay of 283.6 sec/veh (LOS F) due to the large amount of vehicle turning right towards I-285.

This movement has a delay of 356.3 sec/veh.

o PM peak hour, the Cobb Parkway southbound approach has the longest delay of 116.8 sec/veh (LOS F) due to the left turning movement of 147.8 sec/veh of

delay. This movement has only 67.0 sec/veh of delay in baseline conditions.

Cobb Pkwy & Cumberland Boulevard/Windy Ridge Pkwy

o PM peak hour the Cumberland Boulevard eastbound approach has the longest

delay of 94.5 sec/veh (LOS E) due to the left turning movement with a delay of 138.0 sec/veh. In baseline conditions this movement only has a delay of 83.2 sec/veh.

Herodian Way at Circle 75 Parkway

o PM peak hour has an overall delay of 527.8 sec/veh at this intersection. This intersection is un-signalized, and the no-build counts include game day traffic.

To maintain functionality at this intersection, there will be an officer on duty directing traffic on game days.

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7. Proposed Improvements

Utilizing the results of the no-build analysis, proposed improvements were identified for deficient

intersections. Drawing upon knowledge from subject matter experts in design, environment, and traffic operations, multiple improvement options were evaluated at different levels of detail. For those improvements which were identified as being reasonably constructible and beneficial enough

to overcome any environmental impacts, a more detailed analysis was completed. For some intersections this resulted in multiple alternatives being evaluated at a detailed operational and design level. The following sections describe the proposed improvements and evaluate the benefits,

discuss operational/capacity implications, and propose a prioritization for implementation of the projects.

7.1 Proposed Improvements and Benefit/Cost Analysis

When prioritizing transportation improvement projects, two of the most important factors are project

costs and benefits delivered. A comparison of these factors in the form of a benefit to cost ratio aids in identifying the projects which will have the greatest positive economic impact. To determine the approximate costs for this study, detailed schematics were created for each proposed improvement.

Using these schematics, costing plans were developed using a standardized project cost template. Similarly, a standardized template was used to calculate the economic benefits of decreases in vehicle delay resulting from each improvement project.

During this study, project costs and benefits were forecasted for four concepts from the original DRI and seven additional concepts. The four DRI concepts were combined into three concepts based

on their locations for the purposes of this study: DRI-A involves improvements on Cobb Parkway and I-285 Eastbound Ramps, DRI-B/C involves improvements for Cobb Parkway, Circle 75 Parkway, and I-285 Westbound Ramps, and DRI-D involves improvements at Cobb Parkway and

Windy Ridge Parkway.

In addition to the DRI concepts, seven concepts were also analyzed for project costs and benefits.

Six proposed concepts (Cobb-A to -E and Cobb 1) improve or modify existing roadways, while one concept (Cobb-2) involves realignment of existing roads and the construction of new roads. Figure 5 shows a map of the proposed improvement project locations.

Costing plans and benefit analyses for each of the proposed transportation improvements and a short description of each project can be found on the next page. Conceptual schematics for all

proposed transportation improvements can be found in Appendix C. Project sheets providing information on volumes, proposed improvements, capacity analysis results, and benefit/cost information can be found in Appendix E.

Figure 5: Proposed ProjectsLegend



0 0.50.25Miles

Supplemental Segment

DRI Intersection

Supplemental Intersection

Terrell

Mill Road

Windy Hill Road

Windy R

idge P

kwy

Cumberland Blvd

Cobb Pkwy

Powers Ferry Rd

C

AB

C

E

D21

A

B

XX


Improvement Study

24

Cobb – A: Northside Drive at New Northside Drive/Interstate N Parkway

Cobb-A involves improvements for Northside Drive at New Northside Drive/Interstate N Parkway.

For this improvement, the westbound turn lane on New Northside was changed to a through right, and an additional westbound lane was added to Interstate N Parkway to Riveredge Lane. This project would not preclude the construction of a multi-use trail along Interstate N Parkway as

planned by the County and the City of Sandy Springs. Plans for future trail expansions should be considered in the design phase of this project. This could include the placement of mast arms and necessary right-of-way acquisitions.

Primary costs for this project are right-of-way acquisition for the new lane and construction costs for the new lane. Annual savings from the improved traffic operations are estimated at approximately

$420,000. The proposed build conditions result in a significant improvement in overall delay in the concept area when compared to no-build, leading to a benefit/cost ratio of greater than 1.0. Detailed cost and benefit tables for Cobb-A can be found below in Table 5 and Table 6.

Table 5: Estimated Costs for Cobb-A

Cost Description Cost

Preliminary Engineering $126,271

Right-of-Way $1,807,699

Utility $36,077

Construction $1,857,985

Total $3,828,032

Table 6: Estimated Benefits for Cobb-A

Benefit Analysis

Annual Benefit: $420,511

Design Life 20 years

Benefit/Cost Ratio 1.16

25

Cobb – B: Powers Ferry Road at Terrell Mill Road

Cobb-B involves improvements to Powers Ferry Road and Terrell Mill Road. For this improvement,

a 2nd eastbound right turn was added to Terrell Mill Road, a free-flow northbound right turn was added to Powers Ferry Road, and the 3rd northbound lane on Terrell Mill was extended to the intersection with Delk Road. This project would not preclude any future trail plans the County has at

this intersection. Plans for future trail expansions should be considered in the design phase of this project. This could include the placement of mast arms and necessary right-of-way acquisitions.

The single largest cost for this project is right-of-way acquisition for the new turning lanes and additional northbound lane. Dense commercial and residential development in the area to be acquired will significantly increase project costs. Annual savings from the improved traffic operations

are estimated at approximately $258,000. Because of the high right-of-way acquisition costs and the minor operational differences between build and no-build conditions, the benefit/cost ratio of this project is significantly less than 1.0. Detailed cost and benefit tables for Cobb-B can be found below

in Table 7 and Table 8.

Table 7: Estimated Costs for Cobb-B




Utility $55,587


Total $5,977,888

Table 8: Estimated Benefits for Cobb-B

Benefit Analysis




26

Cobb – C: Cumberland Parkway at Cumberland Boulevard

Cobb-C involves improvements at the intersection of Cumberland Parkway and Cumberland

Boulevard. For this improvement, a 2nd northbound left turn was added to Cumberland Boulevard. Additionally, the existing split phasing for the intersection was eliminated by improving the southbound left turn lane spacing. While this improvement would not construct exclusive bus lanes

identified through the Connect Cobb study, it would not prevent the construction of those lanes in the future. Plans for bus exclusive lanes should be considered in the design phase of this project. This could include the placement of mast arms and necessary right-of-way acquisitions.

Annual savings from the improved traffic operations are estimated at approximately $87,000. The high cost of dense commercial right-of-way acquisitions and construction costs for this project

decrease its benefit/cost ratio to less than 1.0. Detailed cost and benefit tables for Cobb-C can be found below in Table 9 and Table 10.

Table 9: Estimated Costs for Cobb-C



Right-of-Way $869,742

Utility $20,883


Total $2,039,201

Table 10: Estimated Benefits for Cobb-C

Benefit Analysis




27

Cobb – D: Powers Ferry Road at Akers Mill Road

Cobb-D involves improvements to the intersection of Powers Ferry Road and Akers Mill Road. For

this improvement, a 2nd eastbound left turn was added to Akers Mill Road and the existing westbound right on Akers Mill Road was converted into a yield right turn. This project would not impact newly constructed trails in the vicinity of the intersection.

Because the project can be completed using existing right-of-way, construction costs make up the majority of the project costs. Annual savings from the improved traffic operations are estimated at

approximately $150,000. The operational improvements result in significant annual savings; the overall benefit/cost ratio of this project is greater than 1.0. Detailed cost and benefit tables for Cobb-D can be found below in Table 11 and Table 12.

Table 11: Estimated Costs for Cobb-D



Right-of-Way $0

Utility $20,947


Total $1,173,052

Table 12: Estimated Benefits for Cobb-D

Benefit Analysis




28

Cobb – E: Windy Ridge Parkway at Interstate N Parkway

Cobb-E involves improvements to the intersection of Windy Ridge Parkway and Interstate N

Parkway. For this improvement, a 2nd northbound left turn was added to Interstate N Parkway and the proposed lane diet from Cobb-1 was also implemented. This project would allow for the construction of a trail or other pedestrian facilities necessary to to support daily and event pedestrian

movements. Plans for future trail expansions or pedestrian facilities should be considered in the design phase of this project. This could include the placement of mast arms and necessary right-of-way acquisitions.

Because the project can be completed using existing right-of-way, construction costs make up the majority of the project costs. Annual savings from the improved traffic operations are estimated at

approximately $5,000. The main benefits of the Cobb-E concept lie in pedestrian capacity and safety improvements, not in reducing overall vehicle delay. Therefore, benefit/cost ratios are not appropriate for this concept. A detailed cost estimate for Cobb-1 can be found below in Table 13.

Table 13: Estimated Costs for Cobb-E



Right-of-Way $0

Utility $19,718


Total $1,104,230

29

Cobb – 1: Interstate N Parkway Lane Diet

Cobb-1 involves a lane diet along the existing right-of-way on Interstate N Parkway between Windy

Hill Road and Windy Ridge Parkway. For this improvement, the existing four lane roadway was narrowed to one lane in each direction with a center left turn lane and was terminated before intersecting with Windy Hill Road. Sidewalks were widened from five feet to twelve feet to provide

greater pedestrian capacity and safety.

Because the project can be completed using existing right-of-way, construction costs make up the

majority of the project costs. The main benefits of the Cobb-1 concept lie in pedestrian capacity and safety improvements, not in reducing overall vehicle delay. Therefore, benefit/cost ratios are not appropriate for this concept. A detailed cost estimate for Cobb-1 can be found below in Table 14.

Table 14: Estimated Costs for Cobb-1



Right-of-Way $0

Utility $29,051


Total $1,626,863

30

Cobb – 2: Interstate N Circle Realignment

Cobb-2 involves the realignment of Interstate N Circle from Windy Ridge Parkway to Windy Hill

Road. To accomplish this realignment, a new bridge would be built across Rottenwood Creek. Additionally, Interstate N Parkway and the existing western portion of Interstate N Circle would be re-aligned to connect with this new road. When combined with Cobb-1, this would re-route the

primary flow of traffic away from Interstate N Parkway and create a safer path for pedestrians accessing SunTrust Park.

Because the project requires the acquisition of commercial real estate and driveway impacts, right-of-way costs are approximately $12,000,000. The main benefits of the Cobb-2 concept lie in re-routing traffic, pedestrian capacity, and pedestrian safety improvements. Furthermore, since Cobb-2

is a new road, no existing conditions or delay exist to create a benefit analysis. Therefore, benefit/cost ratios are not appropriate for this concept. A detailed cost estimate for Cobb-2 can be found below in Table 15.

Table 15: Estimated Costs for Cobb-2




Utility $247,142


Total $25,765,663

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DRI – A: Cobb Parkway at I-285 Eastbound Ramps

DRI-A involves improvements to the intersection of Cobb Parkway and the I-285 Eastbound Ramps.

For this improvement, the outside shoulder of the I-285 eastbound exit ramp will be re-striped as a 3rd eastbound right turn lane.

This project can be completed at minimal cost, uses no additional right-of-way, and provides a significant improvement in operational delay. Annual savings from the improved traffic operations are estimated at approximately $135,000. The operational improvements result in significant annual

savings; the overall benefit/cost ratio of this project is substantially greater than 1.0. Detailed cost and benefit tables for DRI-A can be found below in Table 16 and Table 17.

Table 16: Estimated Costs for DRI-A



Right-of-Way $0

Utility $4,952

Construction $255,039

Total $277,324

Table 17: Estimated Benefits for DRI-A

Benefit Analysis




32

DRI – B: Cobb Parkway at Spring Road, Circle 75 Parkway, and I-285 Westbound Ramps

DRI- B involves improvements to Spring Road and Cobb Parkway at Circle 75 Parkway and the I-

285 Westbound Ramps. For these improvements, Spring Road was widened to three westbound lanes, the intersection of Cobb Parkway and Circle 75 Parkway was modified to have triple lefts northbound and westbound and split phasing was removed, and a channelized lane from the I-285

Westbound Ramps to Circle 75 Parkway was created.

Right-of-way acquisition and construction costs for the lane widening and channelized lane are

estimated to cost a total of approximately $4,500,000, due to the dense commercial nature of the project area. Annual savings from the improved traffic operations are estimated at approximately $5,910,000. Although the costs are significant, the recommended improvements deliver the highest

benefit/cost ratio of any proposed project because of their proximity to SunTrust Park and Cobb Parkway. Detailed cost and benefit tables for DRI- B can be found below in Table 18 and Table 19.

Table 18: Estimated Costs for DRI-B




Utility $397,195


Total $5,370,811

Table 19: Estimated Benefits for DRI-B

Benefit Analysis

Annual Benefit: $5,909,572



33

DRI – C: Cobb Parkway at Windy Ridge Parkway

DRI-C involves improvements to the intersection of Cobb Parkway and Windy Ridge Parkway.

While the DRI proposed multiple improvements for this intersection, it has been determined through coordination with agency stakeholders that neither of the proposed improvements are preferred. The new proposal is to extend the southbound left turn lane from its current length of 200 feet to a

distance of 340 feet. Additionally, the westbound left turn lane would be extended by 230 feet to a distance of 400 feet. This project would not preclude the construction of a planned multi-use trail by the County and while the evaluation for this project does not include the addition of bus exclusive

lanes, the improvements proposed would not prohibit the construction of those lanes in the future. Plans for future bus exclusive lanes should be considered in the design phase of this project. This could include the placement of mast arms and necessary right-of-way acquisitions.

This project can be completed at minimal cost, uses no additional right-of-way, and while it would not show an improvement from a Highway Capacity Manual (HCM) standpoint, it would provide

operational benefits. Due to the fact that HCM delay is expected to remain unchanged, there will not be apparent benefits shown through Synchro. However, this project would result in operational benefits in the field and also would provide safety benefits by reducing the amount of traffic queued

in the through lanes. Detailed cost and benefit tables for DRI-C can be found below in Table 20 and Table 21.

Table 20: Estimated Costs for DRI-C



Right-of-Way $0

Utility $4,777

Construction $245,990

Total $267,484

34

7.2 Intersection and Arterial Capacity Analysis Summary (With Improvements)

After improvements operations at many of the intersections are expected to improve over the no-

build condition. While all of the intersections will not operate at acceptable LOS, all intersections have delays equal to or lower than the baseline conditions. Table 22 below shows the average delay per vehicle in seconds and the LOS for each study intersection for the build AM and PM peak

hours.

Table 21: Build Intersection Delay (sec/veh) and LOS

Intersection AM Peak hour PM Peak Hour


22.5 (LOS C) 28.7 (LOS C)

Powers Ferry Road at Terrell Mill Road 101.2 (LOS F) 55.8 (LOS E)


40.3 (LOS D) 50.0 (LOS D)


Windy Ridge Parkway at Interstate N Parkway 28.7 (LOS C) 61.2 (LOS E)

Cobb Parkway at I-285 Eastbound Ramps 45.6 (LOS D) 52.0 (LOS D)

Cobb Parkway at I-285 Westbound Ramps 25.0 (LOS C) 54.1 (LOS D)


Road 82.9 (LOS F) 69.6 (LOS E)

Cobb Parkway at Windy Ridge Parkway 36.7 (LOS D) 60.6 (LOS E)

For the intersections operating at a level of service of E or F from the table above, further analysis is done to determine which approach at the intersection is causing the most overall delay.

Powers Ferry & Terrell Mill Rd

o AM peak hour eastbound approach has the longest delay of 197.3 sec/veh (LOS F)

due to the eastbound right turning movement which has a delay of 337.7 sec/veh. The improvements at this intersection focus on the northbound approach. While, the eastbound delay increases, the overall intersection delay in improved.

o PM peak hour eastbound approach has the longest delay of 87.2 sec/veh (LOS F) due to the eastbound through movement with a delay of 94.1 sec/veh. The delays of both the eastbound and westbound approaches improve by 10.1 and 21.6

sec/veh respectively from no-build to build conditions.

35

Powers Ferry and Akers Mill Road

o PM peak hour the eastbound approach has the longest delay of 108.3 sec/veh (LOS F) due to the eastbound left turning movement with a delay of 196.3 sec/veh.

This turning movement delay is decreased by 62.7 sec/veh from no-build to build conditions.

Windy Ridge Pkwy & Interstate N Pkwy

o PM peak hour the eastbound approach has the longest delay of 78.4 sec/veh (LOS E) due to the eastbound through movement with a delay of 90.1 sec/veh. Improvement at this intersection were increasing traffic flow for the northbound

vehicles; so, while the eastbound approach experiences a slightly longer delay after improvements have been implemented, the overall delay of the intersection is improved.

Cobb Pkwy & Circle 75/Spring Rd

o AM peak hour the southbound approach has the longest delay of 76 sec/veh due to the left turning movement which has a delay of 171.9 sec/veh. The overall delay of

this intersection was improved by 76.2 sec/veh from no-build to build conditions.

o PM peak hour the westbound approach has the longest delay with a LOS F due to the westbound left turning movement with a delay of 297.2 sec/veh. This will be

due to high traffic volume leaving the site. The overall delay of this intersection is improved by 22.8 sec/veh from no-build to build conditions.

Cobb Pkwy & Windy Ridge Pkwy

o Based on HCM methodologies the delays will not change based on minor operational improvements such as turn bay extensions. This means that delays in build conditions are expected to similar to no build with the exception of small

changes do to signal timing. The extension of the turn lane will provide an operational benefit by removing some of the queue from the travel lane.

o In the AM peak hour, northbound and eastbound left turns are expected to have the

longest delays, 98.4 sec/veh and 85.8 sec/veh.

o In the PM peak hour, northbound, southbound, and eastbound left turns are expected to experience significant delays of over 150 sec/veh each.

36

7.3 Prioritization Methodology and Scheduling of Proposed Improvements

Transportation improvements are complex undertakings that balance a number of competing factors

such as costs, benefits, system connectivity, and constructability. The purpose of prioritizing proposed improvements is to maximize return on investment by programming projects with a good benefit to costs ratios that improve system connectivity and are constructible first. Therefore, a

prioritization methodology was developed to evaluate proposed improvements based on merit and to determine a logical sequence for implementation.

Each proposed improvement was rated using evaluation measures based on the study goals and objectives. Quantitative data and transportation needs from an analysis of existing and future conditions were used to determine a numerical score for each evaluation measure. Examples of

quantitative data include current and future LOS and predicted project benefits. Projects that rank well based only on merit and need might not provide key connections or may be difficult to implement. To address these potential issues, evaluation measures for network connectivity and

constructability were incorporated into the prioritization methodology.

The prioritization methodology is designed to be transparent to decision makers, stakeholders, and

citizens. Transparency is achieved by assigning each project a number grade across several evaluation criteria presented in a prioritization table and widely distributing this information. The prioritization process is described in detail as follows, starting with an overview of the goals and

objectives.

7.3.1 Study Goals and Objectives

Goal 1: Address the needs of the traveling public and minimize traffic impacts caused by the proposed developments

o Objective 1: Maintain or improve the existing (2014) intersection LOS in the horizon year (2019)

o Objective 2: Maintain or improve the existing (2014) system wide performance in the horizon year (2019)

Goal 2: Implement projects in a timely and cost effective manner

o Objective 1: Identify projects with a high degree of constructability

o Objective 2: Leverage funding partnerships between agencies

37

7.3.2 Prioritization Methodology

The prioritization methodology is divided into two key categories: need and implementation. The

need category is comprised of evaluation measures that rate how well a proposed project meets the goals and objectives or addresses existing deficiencies. In the implementation category evaluation measures rate a proposed project on construction difficulty, funding availability, and partnerships.

For rating projects, a scale of 1 to 3 points is used for most evaluation criteria, with more points given for better meeting the criteria. A scale of 1 to 5 was used for some criteria to increase their

weight. The points for each performance measure were then summed to determine a total score for each project. The evaluation criteria rating scheme is detailed as follows:

Need

o How close is the proposed project to the site? 5 points if the project is adjacent to the site, 3 points if the project is on a potential ingress or egress route, and 1 point if the project is in the study area.

o Does the project address an existing problem? 3 points if the project addresses an intersection that is currently at LOS F, 2 points if the intersection is at LOS E, and 1 point if it is at LOS D.

o Does the project address a future need? 3 points if the project addresses an intersection that is forecasted to be at LOS F, 2 points if the intersection is forecasted to be at LOS E, and 1 point if it is forecasted to be at LOS D.

o Does the project have a good benefit cost ratio? Or in other words, is the project a good investment. 5 points if the project has one the top 5 B/C ratios, 3 points if the project has a B/C ratio above 1.0 but is outside of the top 5, and 1 point if the project has a B/C ratio below 1.0. Three points were given to projects where sufficient data is not yet available to calculate a B/C ratio,

o Will the proposed project benefit more than one mode of transportation? 3 points for benefitting 3 or more modes of transportation, 2 points for benefitting 2 modes of transportation and 1 point for benefitting only one mode.

38

Implementation

o How difficult is the project to construct? Are environmental issues anticipated? Will there engineering constraints that are difficult to overcome? 3 points if there are no environmental or engineering constraints foreseen, 2 points if either environmental or engineering constraints are expected, and 1 point if both environmental concerns and engineering constraints are likely.

o Does the project rely on other projects being built to be beneficial? 3 points if the project does not rely on other projects being implemented and 1 point if other projects are required to be built to provide a benefit.

After adding all points from the evaluation criteria, projects were grouped into high and medium priority buckets with higher scoring projects given high priority. The next step was a review of projects in the high priority bucket to determine if they could be open to traffic by 2017. Any projects

likely to have an open to traffic date later than 2017 were reassigned to the medium priority bucket. Finally, within each bucket, engineering judgment was used to recommend an implementation schedule that will maximize benefits from project interconnectivity.

7.4 Prioritization

Table 23 shows a breakdown of the projects based on the point scale for need and implementation of each project. The final score represents how a project should be prioritized. It is recommended

that the higher scoring projects be implemented first based on the seven categories listed. However, the opinion of the public must also be taken into account when deciding on which projects are to be implemented first.

40

8. Funding

Transportation projects are some of the largest investments counties undertake and financing often

comes from a variety of sources at different levels of government. Implementing projects requires funding for preliminary engineering, right-of-way acquisition, utility relocation, and construction. This large commitment of resources across multiple project phases usually requires jurisdictions to

access multiple sources of funding to complete projects.

Transportation funding is available at the local, regional, state, federal, and private levels. The amount of money available generally increases with the size of the jurisdiction or agency. Funding is

usually highest at the federal level and lowest at the local level. In contrast, as the size of the funding entity increases, more restrictions and legal and regulatory requirements are usually included with the money provided. This makes it important to match project sizes and types to

appropriate funding sources.

Revenues available to state and local departments of transportation have been declining for several years and this trend is anticipated to continue. Lower funding levels and the need for more

transportation projects as travel demand continues to increase has resulted in more competition between municipalities for limited funds. In the current economic environment, a combination of traditional revenue sources and innovative financing strategies will be required to fund the

recommended projects in the study area.

A detailed overview of Cobb County’s finances, as well as detailed information on project funding, can be found in Appendix F.

Conclusion

The proposed development has the potential to have an impact on traffic in the immediate vicinity and surrounding area. Several key intersections which already operate at capacity will have

increased delay especially during the PM peak hours when event and retail traffic are at the peak. The projects proposed within this report, along with others planned by the County and Cumberland CID, have the ability to mitigate much of the congestion generated by the development.

As additional details about the development become available, including specific parking locations and gameday routing technologies, the site generated traffic volumes will need to be revised. This

revision will result in changes to the operational and capacity analysis presented in this report.

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