Public Works Staff Report on
Downtown Lighting in Chapel Hill
The purpose of this report, the attached downtown lighting study, and the staff response to recent lighting issues presented to the Town Council, is to assist the Council when considering the recommendations made by the Streetscape Master Plan Review Committee and the Town Manager to revise the Streetscape lighting plan.
On May 23, 2005, the Chapel Hill Town Council directed the Manager to undertake a study of the custom street and pedestrian lighting installed downtown to determine its effectiveness in terms of the evenness, quality and intensity of the light produced by the new fixtures. In June the Town contracted with Cliff C. Parks, Jr., a professional lighting engineer, to evaluate the custom street and pedestrian lighting and prepare the attached report (Attachment 1).
This staff report also responds to a presentation on downtown lighting by Mr. Joe Capowski made to the Town Council on March 27, 2006, and a subsequent responding letter from Ms. Lynne Kane.
Design of the Existing System
The design of the current downtown lighting plan was developed by Edward Stone and Associates, a national landscape architecture firm, in coordination with Duke Power Company and lighting manufacturers in consultation with the Department of Transportation over a period of more than two years during which time custom light fixtures and poles were selected and the appropriate spacing of the lights was determined. The cut-off cobra head streetlight fixture and the Lumec Domus pedestrian light fixture were chosen in order to minimize light pollution, or excessive light spillage being directed up toward the sky or well out beyond the edge of the right-of-way.
The targeted lighting levels of the street and sidewalk meet the guidelines for commercial areas as recommended by the Illuminating Engineering Society of North America, which NCDOT utilizes for its roadway lighting standards. The average 80-foot staggered spacing of the cut-off cobra head streetlights mounted at 30 feet was planned to provide an average lighting level of 1.99 footcandles with a uniformity of 2.80:1 measured on Franklin Street. The pedestrian level lights were planned to be an average of 80 feet apart and mounted 15 feet over the same side of the sidewalk so as to provide a minimum of 0.71 footcandles and a uniformity of 2.97:1 on pedestrian areas.
Existing Downtown Lighting Study
As part of Mr. Parks’ lighting study, photometric measurements were taken downtown to determine the light levels at the sidewalk and roadway levels after dark on the evening of June 15, 2005, concentrating on the 100 blocks of East Franklin and North Columbia Streets where custom lighting was installed in 2003 and 2004. The photometric readings taken at that time indicated a range of sidewalk light levels from 0.2 to 4.0 footcandles, consistent with the average level of 1.99 footcandles that was the criterion when the system of lighting was designed in the 1990’s.
According to the study, the overall quality of lighting on the streets and sidewalks in the study area was generally consistent with the design parameters established by the Town in the early 1990’s in consultation with NCDOT and Duke Power Company. Darker areas were evident where pedestrian lights were not functioning at full capacity and where light was blocked by awnings and tree canopies along the sidewalk, such as at the former Gap store location where the sidewalk is covered by a structure extending from the building.
The summary of the study states that
“The quality of the existing lighting on the streets and sidewalks meets expected levels. Lighting consistency can be improved by eliminating obstructions, adding directional lights, and working with merchants and building owners to enhance ambient lighting from adjacent buildings.”
The study also provided suggestions for increasing the effectiveness of the existing light fixtures by changing the wattage, the color of the light, and/or replacing cut-off lenses with drop lenses.
Response to March 27, 2006 Council Streetscape Lighting Presentation
and Subsequent Petition
On March 27, 2006, the Council received a petition in the form of a PowerPoint presentation from Mr. Joe Capowski for “more creative street lighting downtown” along with a subsequent petition from Ms. Lynne Kane in response to this presentation (Attachment 2). The primary question raised by this presentation and petition involves the Town’s selection of its current lighting fixtures.
When the Streetscape Lighting Plan was originally done, a number of possible light fixtures were selected for use downtown and these fixtures were then considered in discussions with the Town’s Appearance and Historic District Commissions. During these discussions the Lumec pedestrian level fixture currently utilized downtown was selected based on a number of design objectives identified by those reviewing the possible fixture selections. These design objectives included durability and vandal resistance; minimization of light spillage/pollution by utilizing cut-off lenses and covers that direct light down at the sidewalk; and an appearance that was decorative while remaining relatively unobtrusive and unrestricted to a particular architectural period or style.
The fixture used in Lewisburg, Pennsylvania shown by Mr. Capowski in his presentation is Victorian in style and is a much more visually prominent streetscape element than what was desired by those considering the original pedestrian light fixture selections for downtown. The three uncovered globes mounted approximately ten to twelve feet above the sidewalk cast light skywards as well as on to the sidewalk. The fixture also appears more vulnerable to vandalism than what Mr. Stanziale recommended for use in Chapel Hill.
Ms Kane’s concerns expressed in her response to Mr. Capowski’s petition included a desire for town-wide safety through better lighting and that solutions should be economical and energy-efficient without trying to appear “historical.” Ms. Kane suggested “streamlined-classic items” and “a clean design line eclectically mixed with traditional design” as being desirable. We believe that the Town’s custom Lumec pedestrian light fixtures installed in recent years are generally consistent with this description, having a decorative fluted pole with simply styled arms and fixtures. Modifications to the Town’s Lumec fixtures, including modified covers with clear bands and/or lowered lenses are available that make the fixtures more visually prominent, and we believe that in the review of the Streetscape lighting plan these alternative fixture styles may well be considered.
Consideration of Lighting by the Streetscape Master Plan Review Committee
October 2005 – May 2006
The issue of sidewalk lighting generated significant discussion by the Streetscape Master Plan Review Committee; it was considered the single most important Streetscape issue by several Committee members. The results of the lighting study were presented to the Committee in November 2005 using a PowerPoint presentation. Following the presentation, staff conducted an evening tour downtown where custom lighting improvements have been completed so that the Committee members could experience and evaluate the perceived quality of lighting on the sidewalk.
During the subsequent discussion some Committee members indicated that the issue was primarily a need to complete the installation of custom lighting as currently designed and work with private property owners to activate or increase lighting under awnings and on private property. Others in the group saw a need to review the current lighting plan prior to proceeding with future lighting improvements.
Given the lack of full consensus on this issue, and the additional interest the issue of Streetscape lighting has received from other residents in recent petitions to the Council, we believe that hiring an urban lighting specialist to review and revise the current Streetscape lighting plan could be merited. We believe that this work would involve significant coordination with Duke Power Company, the North Carolina Department of Transportation, affected property owners and various Town boards and commissions.
In response to immediate concerns for pedestrian security and safety, staff has obtained approval from the North Carolina Department of Transportation for a proposal to replace the existing cobra head street light fixtures (most of which are 250-watt cut-off fixtures) along the downtown portion of Franklin Street with 400-watt drop lens fixtures. This will increase the overall light level downtown. At this time we are working with Duke Power Company to determine the incremental costs of interim changes to the existing cobra head street light fixtures on existing poles to increase overall lighting levels downtown.