Report to/Rapport au:

Transportation and Transit Committee/

Comité des transports et des services de transport en commun

 

and Council/et au Conseil

10 February 2003/ le 10 février 2003

 

Submitted by/Soumis par:  R.T. Leclair, General Manager/Directrice générale

Transportation, Utilities and Public Works/Transport, services et travaux publics

 

Contact/Personne-ressource:  Michael J. Flainek, P. Eng., Director/Directeur

Traffic and Parking Operations Branch/Circulation et Stationnement

Telephone : 580-2424, extension 26882, Michael.Flainek@ottawa.ca

 

 

Ref N°:  ACS2003-TUP-TRF-0003

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SUBJECT:     SPEED LIMIT REVIEW - NICHOLAS STREET

 

 

OBJET:          EXAMEN DE LA LIMITE DE VITESSE – RUE NICHOLAS

 

 

REPORT RECOMMENDATION

 

That the Transportation and Transit Committee recommend to Council that the 80 km/h speed limit on Nicholas Street be retained and that “No Engine Brakes” signs be installed on Nicholas Street facing northbound motorists approaching Laurier Avenue and southbound motorists approaching Highway 417.

 

 

RECOMMANDATIONS DU RAPPORT

 

Que le Comité des transports et des services de transport en commun recommande au Conseil de maintenir la vitesse à 80 km/h sur la rue Nicholas et d’y poser des panneaux interdisant l’utilisation des freins moteurs par compression, à l’intention des chauffeurs en direction nord approchant de l’avenue Laurier et des chauffeurs en direction sud approchant de l’autoroute 417.

 

 

BACKGROUND

 

At the Transportation and Transit Committee meeting of 20 November 2002, Councillor Doucet submitted a Notice of Motion to reduce the speed limit on Nicholas Street from 80 km/h to 60 km/h and install “No Engine Brakes” signs.  The report was considered at the following meeting and referred to staff for review.

 

Councillor Doucet noted that engine-brake noise has been a concern for a number of years in the community as truck traffic on the King Edward/Nicholas corridor has steadily increased.  Most recently, the matter was raised at the Ottawa East Community Association Annual General Meeting on 12 November 2002.  At issue is the use of engine braking (rapid gear-downs) as truckers decelerate to negotiate ramps at the Queensway/Nicholas interchange or to slow for the traffic control signal at Laurier Avenue.  A map of the area is shown in Annex 1.

 

The community felt that the noise problem would be reduced if the speed limit on Nicholas Street was lowered and "No Engine Brakes" signs were posted.   

 

DISCUSSION

 

During discussion of the report at the Transportation and Transit Committee meeting, it was suggested that as a means of mitigating noise levels along Nicholas Street, staff consider reducing the speed limit for trucks only.  However, the Highway Traffic Act does not permit reduced speed limits specifically for trucks, except on King’s Highways or roadways in territories without Municipal Authority.

 

Further, the issue of truck noise cannot be resolved solely by a speed reduction, whether applicable to heavy trucks only or to all traffic in general.  Reducing the speed limit to 60 km/h would only result in a reduction in the “steady state” operating noise produced by heavy trucks of approximately 3 dB(A) - an amount barely perceptible to the human ear.  Also, if a lower speed limit actually succeeded in reducing the operating speed of trucks on Nicholas Street, the duration of time that residents would be exposed to truck noise would increase, as it would then take longer for trucks to travel through a given distance. 

 

Resolution of the noise issue must therefore focus on reducing engine-brake noise, not “steady state” operating noise, and should be addressed separately from the speed limit.  To deal directly with that noise concern, a work order has been issued to install oversize “No Engine Brakes” signs on Nicholas Street approaching Highway 417 and Laurier Avenue, as shown in Annex 2.  In addition, a request has been sent to the Ministry of Transportation asking that they install similar signs on the entry ramps to Nicholas Street from Highway 417 (Annex 3 refers). 

 

Reducing the speed limit to 60 km/h will result in reduced driver compliance with the posted speed and, because some drivers will attempt to drive at the new lower limit, it will also increase the speed differential between the slower and faster vehicles.  Experience has repeatedly shown that collision rates on multi-lane roadways increase in direct proportion to the speed differential between the faster and slower vehicles - the more compact the range of operating speeds, the lower the collision rates.

 

Further, reducing the speed limit to 60 km/h for all traffic will not significantly reduce overall operating speeds.  This was conclusively demonstrated through extensive surveys conducted on Nicholas Street in the vicinity of Somerset Street between 1986 and 1992.  They consistently revealed 85th percentile* operating speeds of 90 km/h, whether the speed limit was posted at 50 km/h or 80 km/h.  A recent survey conducted at that location in January 2003 showed a similar result.

 

* The 85th percentile speed is the speed at or below which, 85% of the observed vehicles were traveling.

Information contained in both the “Geometric Design Guide for Canadian Roads” and “Managing Speed” by the Transportation Research Board in the United States, conclude that: “the 85th percentile speed is generally at the upper bound of a speed range within which crash involvement rates are lowest.”  The criterion most generally used and preferred in determining the specific maximum speed limit from speed studies is the 85th percentile speed.

 

The high degree of driver conformity with the currently posted speed limit and the compact range of operating speeds between faster and slower vehicles, no doubt contribute to the excellent collision record of this four-lane divided, 80 km/h portion of Nicholas Street.  It carries daily volumes of 37,000 vehicles, including 2,500 heavy trucks, yet during the three-year period ending 31 Dec 2002, only experienced 14 collisions.  While its difficult to draw meaningful comparisons to other roads within the City, simply because there are no other four-lane divided, 80 km/h roads that connect as directly to Highway 417 as does Nicholas Street, it is noteworthy that during the same three-year time span, 15 collisions were reported on West Hunt Club Road in the mid-block section west of Cleopatra Drive and 12 collisions were reported in the mid-block section between Knoxdale Road and Woodroffe Avenue.  Those sections of West Hunt Club Road are also four-lane divided, posted at 80 km/h and operate at 85th percentile speeds of 90 km/h; however, they only carry 75% of the traffic handled by Nicholas Street and only 55% of the truck volumes.  All three road sections are approximately the same length.

 

Accordingly, in view of the foregoing, it is recommended that the existing speed limit of 80 km/h not be reduced on Nicholas Street. 

 

 
FINANCIAL IMPLICATIONS

 

There are no financial implications.

 

 

ATTACHMENTS

 

Annex 1 - Key Plan

Annex 2 - Signing Changes

Annex 3 - E-Mail to Ministry of Transportation

Annex 1

Key Plan

Annex 2

Signing Changes

 

 

Annex 3

E-Mail to Ministry of Transportation

 

 

To:                        bill.brannen@mto.gov.on.ca

Cc:                        Buck, John F; Carmody, Tom W

Subject:                 Request for "NO ENGINE BRAKES" Signage

 

Dear Bill:

 

This e-mail is further to my telephone call last week requesting that Ministry of Transportation (MTO) consider installing  "NO ENGINE BRAKES" signs on the eastbound and westbound exit ramps from Highway 417 to Nicholas Street.

 

 The issue of engine brake noise has been an ongoing concern for a number of years in the community as the truck traffic on the King Edward/Nicholas Street corridor has steadily increased.  Most recently, the matter was raised at the Ottawa East Community Association Annual General Meeting on 12 November 2002.  The primary concerns are related to the use of engine braking (rapid gear-downs), as trucks negotiate the Nicholas Street/ Highway 417 interchange ramps.

 

On 5 March 2003 we will be presenting a report to the Transportation and Transit Committee regarding this matter.  In the report we have indicated that we will be installing oversized "NO ENGINE BRAKES" signs on Nicholas Street (illustrated in the attachment).  We also indicated in the report that we would be contacting MTO to formally request the installation of similar signs on the exit ramps from Highway 417 to Nicholas Street.

 

In light of the concerns and the background information provided in this e-mail could you please review this signing request and provide me with your written comments by 28 February 2003.

 

Thank you.

 

 

 

Douglas Bowron,  M.Eng., P.Eng.

Program Manager, Traffic Investigations and Surveys

Safety and Traffic Services Division

Transportation, Utilities and Public Works Department