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Traffic Impact Study South Shades Crest Road Retail

Skipper Consulting, Inc. BIRMINGHAM, ALABAMA

March 2015

South Shades Crest Road Retail – Hoover, Alabama

Skipper Consulting, Inc. i

Table of Contents Page

Introduction ..................................................................................................................................... 1 Figure 1 – Site Location Map .............................................................................................................. 2

Background Information .................................................................................................................. 3 Roadway and Intersection Descriptions................................................................................................. 3 Proposed Project Description ................................................................................................................. 3

Figure 2 – Study Intersection Aerial Photo ........................................................................................ 3 Existing Traffic Conditions ................................................................................................................ 4

Existing Traffic Counts ............................................................................................................................. 4 Existing Intersection Capacity Analysis ................................................................................................... 4

Table 1 – Existing Peak Hour Intersection Levels of Service ............................................................. 4 Figure 3 – Existing Peak Hour Traffic Volumes .................................................................................. 5

Future Traffic Conditions ................................................................................................................. 6 Trip Generation Estimates ...................................................................................................................... 6

Table 2 –Trip Generation Estimates ................................................................................................... 6 Direction of Approach ............................................................................................................................. 6 Future Traffic Volumes ............................................................................................................................ 7

Figure 4 – Future Peak Hour Traffic Volumes .................................................................................... 8 Roadway and Traffic Control Improvements ................................................................................... 9

Right-Turn Lane Evaluation ..................................................................................................................... 9 Recommended Site Access Lane Geometrics ........................................................................................ 9 Future Conditions Capacity Analysis .................................................................................................... 10

Table 3 – Future Peak Hour Intersection Levels of Service ............................................................. 10 Conclusions .................................................................................................................................... 11 List of Appendices

Appendix A Preliminary Site Plan Appendix B Traffic Count Data Appendix C Existing Conditions Capacity Analyses Printouts Appendix D Future Conditions Capacity Analyses Printouts Appendix E Turn Lane Warrant Analyses Printouts


Skipper Consulting, Inc. 1

Introduction The purpose of this report is to document the findings of a traffic study conducted for a proposed retail development in Hoover, Alabama. The proposed site for the development is located along the west side of South Shades Crest Road north of its intersection with Brocks Gap Parkway. A site location map of the proposed site and the surrounding roadways is provided as Figure 1. For the purposes of this study effort, the proposed development is assumed to consist of a supermarket and a gas/service station. Access to the proposed development is planned via two access driveways along South Shades Crest Road (one fully directional access aligning with Brocks Gap Parkway and one right in/right out only access). The proposed development site plan is included as Appendix A. The purposes of this study are to:

Examine existing traffic conditions within the area of the proposed development site;

Determine the magnitude and direction of approach of any traffic that would be associated with the proposed development;

Examine the projected future traffic conditions with the proposed development in place and occupied; and,

Determine what (if any) roadway/traffic control improvements would be required to accommodate the proposed development.

Sources of information used in this report include the Alabama Department of Transportation, Traffic Data, LLC, US Steel Corp., the Federal Highway Administration, the Transportation Research Board, and office files and field reconnaissance efforts of Skipper Consulting, Inc.

Sources: Esri, HERE, DeLorme, USGS, Intermap, increment P Corp.,NRCAN, Esri Japan, METI, Esri China (Hong Kong), Esri (Thailand),TomTom, MapmyIndia, © OpenStreetMap contributors, and the GIS UserCommunity

Figure 1Site Location MapTraffic Impact Study

Hoover, Alabama

Not to ScaleMarch 2015

I

Study Intersection

Site



Background Information Roadway and Intersection Descriptions South Shades Crest Road is a two-lane roadway. Within the immediate vicinity of the site, the posted speed limit is 45 miles per hour. For the purposes of this study, South Shades Crest Road is considered a north/south roadway. Brocks Gap Parkway is a two-lane roadway with a posted speed limit of 30 miles per hour. For the purposes of this study, Brocks Gap Parkway is considered an east/west roadway. South Shades Crest Road at Brocks Gap Parkway is controlled by traffic signalization. Proposed Project Description As mentioned previously, the proposed development site is located along the west side of South Shades Crest Road and is planned to contain a supermarket and gas/service station. For this study effort, the supermarket is assumed to be approximately 50,000 square feet and the gas/service station is assumed to have 12 fueling positions. Figure 2 illustrates the proposed site location.

Figure 2 – Study Intersection Aerial Photo

Site



Existing Traffic Conditions Existing Traffic Counts To determine the magnitude of existing traffic volumes, traffic counts were conducted at the study intersection. Peak hour traffic counts were conducted at the study intersection for the morning and afternoon weekday peak periods (7:00 to 9:00 a.m. and 4:00 to 6:00 p.m.). Also, a twenty-four hour count was conducted along South Shades Crest Road near the proposed development. Peak hour intersection turning movement counts are illustrated in Figure 3. Detailed traffic count data is provided in Appendix B. Existing Intersection Capacity Analysis Existing peak hour intersection capacity analyses were performed using the methodology outlined in the Highway Capacity Manual, published by the Transportation Research Board. Capacities are expressed as levels of service, and range from a level of service “A” (highest quality of service) to a level of service “F” (lowest quality of service). As a general rule, operation at a level of service “C” or better is desirable, with a level of service “D” considered acceptable during peak hours of traffic flow. The existing peak hour intersection capacity analysis printouts are included in Appendix C and the results are summarized in Table 1. Capacity analyses results, summarized in Table 1, indicate that each approach for the study intersection and the overall intersection currently operates with acceptable levels of service.

Table 1 – Existing Peak Hour Intersection Levels of Service

Intersection Approach Level of Service

AM Peak PM Peak

S. Shades Crest Rd at

Brocks Gap Pkwy (Signalized)

WB Brocks Gap Pkwy D D

NB S. Shades Crest Rd A B

SB S. Shades Crest Rd A B

Overall Intersection LOS B B

South Shades Crest Road Retail - Hoover, Alabama

473

(146

)88

3 (5

62)

174

(916

)10

3 (9

3)

99 (85)123 (284)

S Sh

ades

Cre

st R

d

Brocks Gap Pkwy



Future Traffic Conditions Trip Generation Estimates Trip generation estimates were developed to determine future traffic volumes associated with the proposed development. Trip generation estimates were developed using information presented in Trip Generation Manual, Ninth Edition, published by The Institute of Transportation Engineers. Trips to be generated by the proposed development can be described as a combination of new trips, intercept trips, and mixed-used trips. New trips are defined as traffic that wouldn’t have otherwise traveled the study area roadways. Intercept trips can be described as traffic that would stop at the proposed development while en route to another destination. Intercept trips do not create new traffic along study area roadways, but would create traffic for the proposed site access driveways. A mixed-use rate of five percent (5%) was applied to the projected traffic of the development. Intercept trip rates were determined using the ITE Trip Generation Handbook, by the Institute of Transportation Engineers. For the purpose of this study, the related intercept rates used are 36% for supermarket trips and 58%/42% (am/pm) for gas/service station trips. Table 2 provides a summary of the trip generation estimates for the proposed restaurant development.

Table 2 –Trip Generation Estimates

Direction of Approach In order to determine future traffic volumes, the direction of approach for site generated traffic was developed. To develop the direction of approach, existing traffic volumes were evaluated along with existing population concentrations, and potential site market areas. The following directions of approach were determined for new trips expected to be generated by the proposed development:

Approximately 45% to/from the north via South Shades Crest Road;

Approximately 40% to/from the south via South Shades Crest Road; and

Approximately 15% to/from the east via Brocks Gap Parkway Intercept trip distribution is expected to occur based upon the distribution of traffic on adjacent roadways as summarized in the following:

AM Peak Hour – 70% to/from the northbound traffic flow on South Shades Crest Road, and 30% to/from the southbound traffic flow on South Shades Crest Road; and

Land Use Size Units AM Peak PM Peak

In Out In Out

Supermarket 50,000 s.f. 105 65 238 229

Gas Station with Service Station 12 pumps 70 67 83 83

5% Mixed-Use Reduction 9 7 16 16

Total 166 125 305 296



PM Peak Hour – 30% to/from the northbound traffic flow on South Shades Crest Road, and 70% to/from the southbound traffic flow on South Shades Crest Road

Future Traffic Volumes Trips expected to be generated by the proposed development were added to existing traffic volumes using the directions of approach listed previously resulting in projected future traffic volumes. Projected weekday morning and afternoon peak hour future traffic volumes for the study intersections are included in Figure 4.

South Shades Crest Road Retail - Hoover, Alabama

S S

had

es C

rest

Rd

Brocks Gap PkwyMain Site Access

830 (

527)

86 (

111)

161 (

898)

21 (

53)

103 (

93)

473 (

146)

15 (28)68 (116)

29 (101)

22 (38)99 (85)

114 (274)

Secondary Site Access 13 (51)

997 (

728)

272 (

993)

37 (

103)



Roadway and Traffic Control Improvements Right-Turn Lane Evaluation Guidelines recommended for the addition of a right-turn lane at the proposed site intersections were evaluated using methods outlined in the Intersection Channelization Design Guide, Report 279, and the National Cooperative Highway Research Program (NCHRP) Report 457 Evaluating Intersection Improvements: An Engineering Study Guide, published by the Transportation Research Board. Based on the proposed site plan, a southbound right-turn lane would be applicable at each proposed access. After evaluating the right-turn lane guidelines outlined above for the morning and afternoon peak hours, it was determined traffic volumes would meet the minimum criteria needed to warrant a southbound right-turn lane at both accesses under future conditions. Detailed figures of the right-turn lane warrant evaluations are provided in Appendix E. Recommended Site Access Lane Geometrics Based upon the development of the proposed site, future traffic conditions, and right-turn lane warrant evaluations, recommendations have been developed with regards to the proposed site accesses and study intersection. The following describes these recommended improvements:

South Shades Crest Road at Main Site Access/Brocks Gap Parkway

Construct a left turn lane on northbound South Shades Crest Road approaching Brocks Gap Parkway to accommodate site generated traffic.

Construct a right turn lane on southbound South Shades Crest Road approaching the proposed main site access/Brocks Gap Parkway.

Construct the main site access to provide three outbound lanes (left-turn, through, right-turn) and one inbound lane.

Construct an improved right turn radius with channelization on westbound Brocks Gap Parkway approaching South Shades Crest Road to allow right turn traffic to bypass through vehicles.

Modify traffic signal phasing and timings to accommodate the proposed traffic movements and proposed lane geometry.

South Shades Crest Road at Secondary Site Access

Construct the secondary site access as a right-in/right-out only access with side street stop sign control.

Construct a right turn lane on southbound South Shades Crest Road at the proposed secondary site access.



Future Conditions Capacity Analysis Future peak hour intersection capacity analyses were performed using the methodology outlined in the Highway Capacity Manual, published by the Transportation Research Board. Capacities are expressed as levels of service, and range from a level of service “A” (highest quality of service) to a level of service “F” (lowest quality of service). As a general rule, operation at a level of service “C” or better is desirable, with a level of service “D” considered acceptable during peak hours of traffic flow. Capacity analyses for future (post-development) traffic conditions were conducted assuming the proposed development would be in place and occupied and the recommended roadway and traffic control improvements, outlined above, would be in place. The future peak hour intersection capacity analysis printouts are included in Appendix D and the results are summarized in Table 3.

Table 3 – Future Peak Hour Intersection Levels of Service

Intersection Approach Level of Service

AM Peak PM Peak

S. Shades Crest Rd at

Brocks Gap Pkwy/ Main Site Access

(Signalized)

EB Main Site Access D D

WB Brocks Gap Pkwy C C

NB S. Shades Crest Rd B B

SB S. Shades Crest Rd A D

Overall Intersection LOS B C

S. Shades Crest Rd at Secondary Site Access

(Un-signalized) EB Site Access (Right) A C

The results of future (post-development) capacity analyses indicate that each approach of the study intersection and the overall intersection would continue to operate with acceptable levels of service under future conditions.



Conclusions The following conclusions can be drawn from the information presented previously in this report document:

1. The proposed development site is located along the west side of South Shades Crest Road near its intersection with Brocks Gap Parkway. The proposed development is planned to be accessed by two driveways along South Shades Crest Road (one fully directional aligning with Brocks Gap Parkway and one right in/right out only). The proposed development site is planned to contain a supermarket and a gas/service station.

2. Presently, acceptable levels of service are being provided for each approach and the overall intersection of the South Shades Crest Road and Brocks Gap Parkway intersection.

3. The proposed development is planned to generate approximately 307 total trips (175 inbound and 132 outbound) during the morning peak hour, and 633 total trips (321 inbound and 312 outbound) during the afternoon peak hour. It should be noted that a portion of these trips are expected to be intercepted from existing traffic flows on South Shades Crest Road.

4. The following improvements are recommended to accommodate the proposed development. South Shades Crest Road at Main Site Access/Brocks Gap Parkway

Construct a left turn lane on northbound South Shades Crest Road approaching Brocks Gap Parkway to accommodate site generated traffic.

Construct a right turn lane on southbound South Shades Crest Road approaching the proposed main site access/Brocks Gap Parkway.

Construct the main site access to provide three outbound lanes (left-turn, through, right-turn) and one inbound lane.

Construct an improved right turn radius with channelization on westbound Brocks Gap Parkway approaching South Shades Crest Road to allow right turn traffic to bypass through vehicles.

Modify traffic signal phasing and timings to accommodate the proposed traffic movements and proposed lane geometry.

South Shades Crest Road at Secondary Site Access

Construct the secondary site access as a right-in/right-out only access with side street stop sign control.

Construct a right turn lane on southbound South Shades Crest Road at the proposed secondary site access.

5. With post-development traffic volumes in place and implementation of the recommended

roadway and traffic control improvements, the study intersections would operate with acceptable levels of service under future (post-development) conditions.

Appendix A Preliminary Site Plan

Appendix B Traffic Count Data

Appendix C Existing Conditions Capacity Analyses Printouts

Appendix D Future Conditions Capacity Analyses Printouts

Appendix E Turn Lane Warrant Analyses Printouts

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