PURPOSE:

To request Council approval of a resolution authorizing the installation of three-way stop signs at the intersection of Keystone Street and Lamer Street.

BACKGROUND:

Staff received requests from the Starlight Hills residents to investigate street improvements to help reduce speed on Lamer Street.  Staff met with a number of homeowners in the area, and made several site visits to discuss traffic conditions with the residents.  Staff developed a list of potential improvements to streets in the area, and the potential improvements were discussed with residents to gain concurrence.

The Lamer Street traffic issues were discussed at the regular July 2004 Traffic and Transportation Committee meeting, which was attended by a number of residents.  Staff developed recommended improvements in concert with residents of the area and the recommendations were presented to the Traffic and Transportation Committee on November 18, 2004.  The committee endorsed the following:

1. Install three-way stop controls at Lamer Street and Keystone Street � The traffic data at this intersection shows that a majority of the traffic flows between Lamer Street north of the intersection and Keystone Street south of the intersection (about 650 vehicles per day).  However, enough traffic also uses Lamer Street through the intersection to warrant an additional stop sign.

2. Install a STOP AHEAD sign for southbound Lamer Street � The stop sign at Keystone Street is not easily seen by motorists traveling southbound on Lamer Street. Staff recently installed the �Stop Ahead� sign with the intent of reducing the speed of vehicles traveling down the hill.

3. Install a double yellow centerline around the curve on Lamer Street north of Keystone Street � The double yellow centerline will provide increased guidance for drivers around the curve. Staff recently installed the double yellow lines on Lamer Street from Keystone Street to Whitney Lane.

4. Install speed advisory (25 MPH) signs on Lamer and on other streets near Brace Canyon Park � These signs are intended to remind drivers of the residential neighborhood.  We have installed similar signs on streets near the De Bell golf course and Stough Park with some success. The installation of these signs is combined with the city-wide speed limit signs that are currently being installed.

ANALYSIS:

Keystone Street and Lamer Street are both residential collector streets. Presently Lamer Street has a stop sign at Keystone Street. The average daily traffic on these roads is as follows:

Lamer Street north of Keystone Street = 1,755 vehicles per day

Lamer Street east of Keystone Street =    550 vehicles per day

Keystone Street west of Lamer Street = 1,350 vehicles per day

As shown above, the current traffic on Lamer Street (north of Keystone Street) has a higher traffic volume than Keystone Street, but traffic stops for the other two traffic movements. Standard traffic engineering practice is to stop the lower traffic volume street for the higher volume street.  Thus, Lamer Street east of Keystone Street should stop for the other approaches.  The accident experience at the intersection is very good, with no reported accidents within the last three years.

A speed survey was taken on the three approaches and the 85^th percentile speeds are as follows:

Lamer Street north of Keystone Street = 31 MPH

Lamer Street east of Keystone Street = 30 MPH

Keystone Street west of Lamer Street = 38 MPH

This is a wide 3 legged intersection in a hillside area.  The latest guidelines established by the State of California, as well as the Manual of Unified Traffic Control Devices (MUTCD) indicate that a multi-way stop is appropriate for the intersection.  The intersection does not meet the accident or volume criteria, but it meets general criteria for installation of a multi stop. The criteria allows the engineer to install a multi stop if �an intersection of two residential neighborhood collector (through) streets of similar design and operating characteristics where multiway stop control would improve traffic operation characteristics of the intersection�.

Therefore, Staff recommends that the Council approve the installation of the three way stop at the intersection of Keystone Street and Lamer Street.

FISCAL IMPACT:

The installation and maintenance costs of the signs are budgeted in the Signs and Markings Section of the Traffic Engineering Division.  The estimated cost is $150.

RECOMMENDATION:

It is recommended that the Council adopt a resolution approving the installation of multi stop signs at intersection of Keystone Street and Lamer Street.

Attachment:          Traffic and Transportation Committee Report

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