Fairview Village Shopping Center
Traffic Impact Study – April 1, 2005
Prepared by Martin Alexiou Bryson (MAB)

5.0 Findings and Conclusions

Roadway Improvements

The intersection of Ten Ten Road at Holly Springs Road operates at a failing level of service in the A.M. and P.M. peak hours with and without the site traffic in the future scenarios.  Overall intersection delay increases between Background (2008) and Build (2008) scenarios by 16 seconds in the A.M. peak hour and 180 seconds in the P.M. peak hour.  The following is recommended to help mitigate the impacts of the site traffic at the Ten Ten Road and Holly Springs Road intersection:

Ten Ten Road at Holly Springs Road (signalized)

·    Construct an exclusive southbound through/right lane along Holly Springs Road with at least 300 feet of storage.
Extend the southbound through lane from Ten Ten Road to Les Arbres Drive along Holly Springs Road and drop it as a right-turn lane.

·     Construct an exclusive eastbound right-turn lane along Ten Ten Road with at least 150 feet of storage.

·     Extend the southbound left-turn lane from the existing 150 feet of storage to 300 feet of storage.

·     Construct an exclusive northbound right-turn lane along Holly Springs Road with at least 150 feet of storage.

·     Upgrade the signal timing to allow for a protected/permissive northbound left phase as well as overlaps for the northbound and eastbound right-turn movement.

·     Extend the northbound left-turn lane to provide at least 200 feet of storage. 

·     Extend the westbound left-turn storage to form a continuous turn lane between the Holly Springs Road
intersection and the Site Access 5 driveway.

In order to bring the intersection of Ten Ten Road at Holly Springs Road to LOS D in 2008 under Build conditions, an additional through-right lane is required in the northbound and eastbound directions.  However, the Town of Cary does not require the developer to bring an intersection that is failing under Background conditions to an acceptable level of service.

The intersection of Penny Road at Holly Springs Road operates at a failing level of service in the A.M. and P.M. peak hours with and without the site traffic in the future scenarios.  Overall intersection delay increases between Background (2008) and Build (2008) scenarios by 6 seconds in the A.M. peak hour and 28 seconds in the P.M. peak hour.  The following is recommended to help mitigate the impacts of the site traffic at the Penny Road and Holly Springs Road intersection.

Holly Springs Road at Penny Road (signalized)

·         Construct an exclusive southbound right-turn lane along Holly Springs Road with at least 150 feet of storage. 

·         Construct an exclusive westbound right-turn lane along Penny Road with at least 150 feet of storage.

·         Construct an exclusive eastbound right-turn lane along Penny Road with at least 150 feet of storage.

·         Upgrade the signal timing to allow for overlaps for the southbound and westbound right-turn movements.

The intersection of Holly Springs Road at Arthur Pierce Road operates at a failing level of service in the A.M. and P.M. peak hours in the Build (2008) scenario.  The addition of site trips causes a decline in level of service from LOS D to LOS F in the P.M. peak hour between Background (2008) and Build (2008) scenarios.  The following is recommended to help mitigate the impacts of the site traffic at the Holly Springs Road at Arthur Pierce Road intersection.

Holly Springs Road at Arthur Pierce Road (unsignalized)

·         Widen the eastbound approach to allow for a left-turn lane of approximately 50 feet in length.

The widening of Arthur Pierce Road to provide a short left-turn in the eastbound direction returns the approach to LOS E under Build (2008) conditions, but not to the Background LOS D as required by the Town of Cary Ordinance .  Adding a northbound left-turn lane along the Holly Springs Road would improve the level of service at the intersection, but would create an unsafe weaving movement on that short section between Pierce Olive Road and Arthur Pierce Road .  Ultimately, this intersection should be re-aligned with Pierce Olive Road to provide a four-leg intersection with Holly Springs Road .  Along with this re-alignment, left-turn lanes should be provided, and the intersection most likely will require signalization.

Holly Springs Road and Ten Ten Road Widening

The Town of Cary requires that new developments widen the roads along the frontage of the property to the standards set in the Cary Comprehensive Transportation Plan.  For the section of Holly Springs Road adjacent to the site, the Plan dictates an ultimate 102-foot six-lane divided cross-section.  As a result, the developer would be required to provide at least 51-feet of widening which includes a median and three northbound lanes.  Since three northbound lanes do not currently exist upstream or downstream of the site, the additional pavement needs to be constructed, but may be unused in the interim (possibly use pavement markings to hatch out the extra pavement) or could be used as another purpose in the interim such as right-turn pocket lanes which would also meet traffic capacity requirements as listed below.  The specific roadway design will be at the discretion of the developer, but will require review and approval by the Town of Cary Department of Engineering.  Similarly, the eastbound direction of Ten Ten Road which fronts the site would need to be widened to meet the cross-section requirements detailed in the Comprehensive Plan.

Table 10 summarizes the analysis results for each of the scenarios and Figure 15 illustrates the future lane configurations in conjunction with the proposed site plan in Figure 2.

Site Access

Site Access 1 and Site Access 5 (the full-access driveways) are projected to operate at LOS F during both peak hours.  Left-turn delays out of these driveways will be severe and queue lengths will be long.  Therefore, the Build (2008) Improved scenarios were analyzed with the following improvements as shown in Figure 15: 

Holly Springs Road at Les Arbres Drive / Site Access 1 (unsignalized)

·     Construct an exclusive southbound left-turn lane along Holly Springs Road with at least 250 feet of storage.

·     Construct an exclusive northbound right-turn lane along Holly Springs Road with at least 50 feet of storage.

·     Construct an exclusive northbound right-turn lane along Holly Springs Road with at least 100 feet of storage.

·     Provide two egress lanes, one through-right and a left-turn lane, and one ingress lane with at least
200 feet of protected internal stem length.

·     Prepare a formal signal warrant analysis.  Under Build conditions the intersection meets the P.M.
peak hour warrant for signalization. 

Holly Springs Road at Site Access 2 (unsignalized)

·     Stripe for an exclusive northbound right-turn pocket along Holly Springs Road with at least 100 feet of storage.  This does not require any additional widening beyond that required by the Town of Cary Comprehensive Plan and should revert to a through-right lane when Holly Springs Road is built-out to its ultimate cross-section.

·     Provide one egress lane and one ingress lane.  NCDOT requires at least 100 feet of protected internal stem length, which should be provided.

·     Limit the movements entering and exiting the driveway to right-in/right-out only, which likely requires the installation of a median as dictated by the Town of Cary engineering street standards (Detail No. 03000.09).

  Holly Springs Road at Site Access 3 (unsignalized)

·     Stripe for an exclusive northbound right-turn pocket along Holly Springs Road with at least 100 feet of storage.  This does not require any additional widening beyond that required by the Town of Cary Comprehensive Plan and should revert to a through-right lane when Holly Springs Road is built-out to its ultimate cross-section.

·     Provide one egress lane and one ingress lane.  NCDOT requires at least 100 feet of protected internal stem length, which should be provided.

·     Limit the movements entering and exiting the driveway to right-in/right-out only, which likely requires the installation of a median as dictated by the Town of Cary engineering street standards (Detail No. 03000.09). 

Holly Springs Road at Site Access 4 (unsignalized)

·     Stripe for an exclusive northbound right-turn pocket along Holly Springs Road with at least 100 feet of storage.  This does not require any additional widening beyond that required by the Town of Cary Comprehensive Plan and should revert to a through-right lane when Holly Springs Road is built-out to its ultimate cross-section.

·     Provide one egress lane and one ingress lane.  NCDOT requires at least 100 feet of protected internal stem length, which should be provided.

·     Limit the movements entering and exiting the driveway to right-in/right-out only, which likely requires the installation of a median as dictated by the Town of Cary engineering street standards (Detail No. 03000.09). 

  Ten Ten Road at Site Access 5 (unsignalized)

·     Construct an exclusive westbound left-turn lane along Ten Ten Road with at least 200 feet of storage.

·     Construct an exclusive eastbound right-turn lane along Ten Ten Road with at least 100 feet of storage. This lane is in addition to the widening required by the Town.

·     Provide two egress lanes and one ingress lane.  NCDOT requires at least 100 feet of protected internal stem length, which should be provided.

Additional Considerations

Even with these improvements, the levels of service do not improve to acceptable standards at the full-access driveway along Ten Ten Road .  Long delays are expected exiting the site driveway due both to the shear volume along Ten Ten Road and the backup from the upstream signalized intersection of Holly Spring Road and Ten Ten Road .  Therefore, consideration should be given to restricting exiting left-turn movements at Site Access 5 to improve levels of service at those locations. 

Given the long queues extending from the Holly Springs Road and Ten Ten Road signalized intersection, restricting left-turn access from Site Access 5 would provide a safer operating condition.  Westbound queues from the signal will back through the Site Access 5 intersection during peak periods.  An alternative solution would be to allow left-turns into this driveway (often referred to as a left-over), as well as right-turns in and out.

Further, the driveway spacing between Access 3 and Access 4 does not currently meet the Town of Cary Standard Specifications 400-foot minimum spacing standard (Section D.1, page 03000-7).  An alternative solution would be to eliminate one of the right-in/right-out site accesses along Holly Springs Road to allow for better spacing of the other access points.  To accomplish this, consideration should be given to combining Accesses 2 and 3 into a restricted access driveway to allow for right-in/right-out, but with a left-over option.  This combined driveway should be centrally located between Access 1 and Access 4.

 Table 1   Summary of LOS Results

Intersection

Existing (2004)

Background (2008)

Build (2008)
Without
Improvements

Build (2008)
With
Improvements

A.M.

P.M.

A.M.

P.M.

A.M.

P.M.

A.M.

P.M.

Ten Ten Rd at Kildaire Farm Rd

C

(23.9 sec)

C

(23.7 sec)

C

(34.4 sec)

D

(38.7 sec)

D

(35.9 sec)

D

(47.9 sec)

D

(35.9 sec)

D

(47.8 sec)

Eastbound Approach

C

C

D

D

D

E

D

E

Westbound Approach

C

C

D

C

D

C

C

C

Northbound Approach

C

C

C

C

C

C

C

C

Southbound Approach

B

C

B

D

C

E

C

E

Ten Ten Rd at Holly Springs Rd

E
(70.8 sec)

D
(53.9 sec)

F
(92.7 sec)

F
(128.0 sec)

F
(109.2 sec)

F
(308.2 sec)

F
(86.5 sec)

F
(101.2 sec)

Eastbound Approach

E

D

F

F

F

F

F

F

Westbound Approach

E

D

E

C

E

D

E

C

Northbound Approach

F

E

F

F

F

F

F

F

Southbound Approach

E

E

E

F

E

F

E

F

Ten Ten Road at West Lake Rd

B
(12.3 sec)

B
(10.6 sec)

C
(25.5 sec)

B
(14.8 sec)

C
(30.6 sec)

B
(19.1 sec)

C
(30.6 sec)

B
(19.1 sec)

Eastbound Approach

B

B

C

B

C

B

C

B

Westbound Approach

A

A

C

A

C

B

C

B

Northbound Approach

B

C

C

C

D

C

D

C

Holly Springs Rd at Penny Rd

F
(112.0 sec)

C
(32.3 sec)

F
(158.2 sec)

E
(61.6 sec)

F
(164.3 sec)

F
(89.4 sec)

E

(78.5 sec)