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File #: 16-0240    Version: 2 Name:
Type: Discussion Items Status: General Agenda
File created: 11/10/2016 In control: Town Commission
On agenda: 11/15/2016 Final action: 11/15/2016
Title: Traffic Discussion Summary: Discussion of traffic overall in the town.
Attachments: 1. 1997 traffic study
Date Ver.Action ByActionResultAction DetailsMeeting DetailsAudio
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Summary

To: Mayor and Commissioners

From: Micah Maxwell, Town Manager

Date: 11/10/2016

______________________________________________________________________

Subject:

Title

Traffic Discussion

 

Summary:

Discussion of traffic overall in the town.

End

Body

Previous Commission Action: None

Background/Problem Discussion:

In 1997 the Town commissioned a traffic study which identified areas where traffic calming should occur and prioritizing specific elements of that traffic calming into three phases.  The study included data collection from 18 different locations throughout town, found on page 10 of the report, and the subsequent priority ranking of where the needs were greatest. 

Phase I

The roadways listed with the highest priority index were generally placed in phase I of the traffic calming project.  This included all of Indian Rocks Road, Belleview, Cypress, and Poinsettia.  Ponce de Leon and Belforest we also include in phase one, but were not high priority.  For the purpose of this conversation I have included only information on the higher priority Phase I areas. 

Indian Rocks Road  - Pages 12, 18-20

Indian Rocks Road included three data collection results, which account for the top three highest scoring data points on the priority index.  The narrative outlined the need to drop speeds to the posted amount to try and get traffic to divert to an alternative route.  The resulting recommended treatment options for this areas were roundabouts at Rosery, Poinsettia, Ponce, and Bayview/Carl along with raised intersections at Pineland, Althea, Eastleigh, Roebling North, and Belleview. 

Using the same methodology used during the 1997 study, staff input the data from subsequent traffic studies to see if the priority ranking changed in these areas. 

Indian Rocks South

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

11732

3000

200

38.5

30

10432

2009

10989

3000

200

35

30

8989

2011

5383

3000

200

35

30

3383

2013

9547

3000

200

35

30

7547

 

Indian Rocks Central

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

10571

3000

200

36

30

8771

2011

2705

3000

200

35

30

705

2012

7173

3000

200

35

30

5173

2013

6406

3000

200

31

30

3606

 

Indian Rocks North

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

10328

3000

200

37

30

8728

2009

9314

3000

200

38

30

7914

2013

4354

3000

200

36

30

2554

 

1During the 2011 counts, Indian Rocks Road was closed at Belleview Blvd

2During the 2013 counts, Druid Road was under heavy construction.  

3Data collection was not taken at the same exact points.

It appears that volume has dropped over the last few years along Indian Rocks Road and some speed has reduced in the south area, but not in the central and northern areas.  That said, it is likely that the closure of the Biltmore Hotel, which was after to the 2009 IRR South count, had some large impact to the number of vehicles traversing Indian Rocks Road.  Based on a 200 room hotel, traffic could be effected by between 1800 and 2600 trips per day.  The town has installed a roundabout at Ponce as this report called for, however that is the only action it has taken.  It is possible to install roundabouts and raised intersections in the other areas identified, however road drainage will play a major factor in the cost of the projects, as it did in the Ponce project. 

Belleview - Pages 23-24

Like Indian Rocks, raised intersections were designed to drop speeds and motivate cut through traffic to find an alternative route.  Belleview also included raised crosswalks, which were intended to do the same.  The roundabout at the Belleview/druid intersection was designed with intersection safety in mind.

Using the same methodology used during the 1997 study, staff input the data from subsequent traffic studies to see if the priority ranking changed in these areas. 

Belleview

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

8204

3000

200

34.5

30

6104

2011a

7294

3000

200

34

30

5094

2011b

5880

3000

200

33

30

3480

 

It appears that based on the 2011 counts, which took place prior to the Belleview Blvd reconstruction, the volume on the street has dropped sharply.  It is however assumed that the drop off in volume is directly attributed to the closure of the Belleview Biltmore Hotel.  Based on a 200 room hotel, traffic could be effected by between 1800 and 2600 trips per day.

Cypress - Pages 26-28

The narrative identified that Cypress has a speeding problem, and attributed that problem to overly wide streets, and a speed limit at 30mph that was too high.  The report recommended dropping the speed of Cypress to 25 mph as well as the narrowing of the street with the installation of three center islands to narrow lanes to 9 feet in width. 

Using the same methodology used during the 1997 study, staff input the data from subsequent traffic studies to see if the priority ranking changed in these areas. 

Cypress

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

998

1000

200

40

30

1998

2009a

193

1000

200

34

30

-7

2009b

451

1000

200

32

30

-149

2011a

356

1000

200

29

30

-844

2011b

335

1000

200

29

30

-865

2012

84

1000

200

27

30

-1516

2013

222

1000

200

31

30

-578

 

It appears that volume has dropped significantly since the 1997 study, despite the narrowing never occurring.  The town did drop the speed in 2013.  It is important to note that the original methodology showed cypress as a sub-collector, which would allow more traffic volume, however the street is not classified as such and should be considered a local street.  Below we have made that adjustment to the formula as well as the speed limit adjustment to show updated priority scoring. 

Cypress

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

998

250

200

40

20

4748

2009a

193

250

200

34

20

2743

2009b

451

250

200

32

20

2601

2011a

356

250

200

29

20

1906

2011b

335

250

200

29

20

1885

2012

84

250

200

27

20

1234

2013

222

250

200

31

20

2172

 

Poinsettia - Pages 23-24

Like Indian Rocks, raised intersections were designed to drop speeds and motivate cut through traffic to find an alternative route.  Poinsettia also included raised crosswalks, which were intended to do the same.

Using the same methodology used during the 1997 study, staff input the data from subsequent traffic studies to see if the priority ranking changed in these areas. 

Poinsettia

Year

Volume

Rec Volume Max

factor

85th% speed

posted speed

score

1997

2483

3000

200

36

30

683

2009

2201

3000

200

34

30

1

 

Volume appears to have remained steady, and in at least the instance of the singular study undertaken, speed has reduced.  It appears that the researcher who calculated the previous priority score probably made some sort of adjustment to raise the score to 1200, my assumption is that it is based on the fact that sidewalks did not exist along Poinsettia. 

 

Vertical Traffic Calming

Speed Humps - 5-6 feet long rather than the 1-2 foot speed bump

Speed Cushions - Similar to Speed Humps, but they are separated in the middle to allow emergency vehicles to avoid them  if needed

Speed Tables - Similar size to speed humps, however they rise sharply and level off instead of gradually rising and falling.  This allows it to be used as a pedestrian crossing.

Rumble Strips - small strips that make for an uncomfortable, noisy ride, and can help catch a driver’s attention

 

Horizontal Traffic Calming

Narrowing streets - This entails bringing the curb lines closer together and narrowing the drive lanes

Raised Medians - Instead of bringing curbs closer together, this application places a raised median in the middle of the street, which has the effect of narrowing without impact to the curb line

Choke points - Again similar to narrowing, however they are not continuous, but more sporadic

 

Traffic Control Options

Roundabouts - Similar to IRR and Ponce, but likely smaller

Diverters - This would include cutting streets off from one another and creating a more non-linear path

Stop Lights - Much like IRR and Melenbacher

Stop Signs - Much like IRR and Poinsettia.

 

Expenditure Challenges  N/A

Financial Implications:  N/A

Recommendation:  N/A

Proposed Motion  N/A