Memorandum

City of Lawrence

Department of Public Works

TO:	Mike Wildgen
FROM:	Chuck Soules
CC:	Dave Corliss, Debbie Van Saun, Terese Gorman, Linda Finger
Date:	September 29, 2004
RE:	Street Design/Widths

The City Commission has requested information on development standards and street designs (specifically street widths). There are a number of studies, papers, reports, documents, etc…. that one can find providing several different street widths, typically with respect to residential streets.

Several factors should be considered in the determination of street widths:

- Type of facility/functional classification – residential, collector, arterial

- Parking accommodations

- Bicycle facilities

- Speed – as street widths increase, motorists feel more comfortable and speeds may increase

- Services provided – sanitation, school, emergency, and snow removal operations.

- Impact on neighborhoods

- Costs of right-or-way (property) and the improvements (street)

- Long term maintenance

Following is a list of widths needed/required by various organizations and services:

- The uniform fire code requires a 20’ wide travel lane for emergency vehicles. Additionally, on cul-de-sacs longer than 500’ the bulb radius needs to be a minimum of 50’ per Lawrence Fire Department policy.

- Our snowplows measure 11’ from edge to edge; require a minimum 11’ area to operate. On local (residential) streets where parking is allowed on one side, a minimum street width of 20’ (back of curb to back of curb) would be necessary to have safe snow removal operations.

- Parking lanes (parallel) 7’ to 8’ recommended by AASHTO (American Association of State Highway and Transportation Officials).

- Bike lanes are placed on identified (on bike plan/map) collector streets and, according to AASHTO, should be 4’ (not including the gutter pan).

The City of Lawrence street standards have a long history and have not changed since around 1960. Prior to 1960 a 26’ width for residential streets was common, except in the original town where 30’ and 31’ wide brick and stone streets were constructed in 80’ to 100’ wide rights-of-way. Most of the remaining chip sealed streets were constructed in the 1950’s and are 18’ to 20’ in width. Chip sealed streets typically do not have curb and gutter and have an open ditch for drainage.

In the mid to late 1980’s the Public Works staff evaluated street widths. At that time the trend was to increase the widths; however, Lawrence did not increase/change their standard. The City’s typical section for a residential street is 27’ from back of curb to the back of curb. This provides an 8’ parking area and two 9’ lanes (each curb measures 6” wide and accounts for the additional foot).

There are several neighborhoods (North Lawrence, East Lawrence, Western Hills …) that have chip seal streets. Chip seal streets were acceptable when these streets were constructed. It is not the City’s intent to bring these streets up to today’s standards unless requested by the adjacent property owners and neighborhood. If this request was made the street would be paid for through a benefit district.

The City does not restrict parking on residential streets (unless a problem is identified and the Commission approves a “no parking” zone); therefore, if parking occurred on each side that would leave one 10’ lane available for use by both directions of traffic. This past year the City Commission has made two exceptions to our standard collector street width. On both Folks Road and Harvard Road, from Stonecreek Drive to approximately George Williams Way in Fox Chase South, the Commission decided the street width of 31’ would be acceptable, including bike lanes; this provides a 2’ curb and gutter, 3’ bike lane, and a 10.5’ travel lane in each direction.

The City’s typical section for a collector street is 31’ from back of curb to the back of curb. This provides two 11’ wide lanes and 8’ for parking on one side, if necessary (again the curb is 6” wide and accounts for the additional foot width). If bicycle lanes are required, the width is increased to 36’. This width provides 2’ curb and gutter on each side, 4’ bicycle lane in each direction, and two 12’ driving lanes. The curb and gutter width is not included in the bike lane width. If turning lanes are required typically they would be 12’ wide.

Arterial Streets are sized based on volume, turning movements, and speeds. Arterial streets are typically multiple lanes of a 12’ width, turning lanes, signalized intersections, and sidewalks on both sides.

The City Street Standards are approved through the City’s Administrative Policies, adopted by Resolution 5614. Changes to street widths would be approved with the adoption of a new resolution.

Attached are: