HomeMy WebLinkAboutA010 - Comments from David Oesper & Royce Bitzer on Chamber comments Date: , 1/31/99
To: Mayor and City Council Members
From: David Oesper & Royce Bitzer
Subject: Comments on Chamber Comments on a Possible Lighting Ordinance
Please note: in the following comments, the IESNA refers to the Illuminating Engineering
Society of North America.
We suggest the City develop guidelines rather than an ordinance. These guidelines can be used
as a tool by staff for new developments. We believe this course of action should be the first step
rather than adopting an ordinance.
Citizens and City staff need an effective way to deal with obtrusive lighting. They need
effective tools such as the lighting code to maintain Ames' unique quality of life and
environment. Promoting good lighting should go beyond merely making suggestions that
people are then free to follow or disregard at will. Companies' responses to Ames citizens'
complaints about their lighting have sometimes been less than what one might hope for.
Although some businesses have been responsive to public concern, unfortunately some others
have been rather unresponsive. On a more positive note, everyone benefits from lighting that is
more attractive and energy-efficient, allows people to see better at night, and enhances the
nightscape of Ames in a way that both residents and visitors can appreciate. This policy could
become another selling point to promote the quality of life in Ames. We feel the most effective
way to bring about these potential benefits is through an ordinance.
We believe that the lighting ordinance as currently proposed represents a good compromise and
will not cause undue hardship on any business or individual. In fact, the proposed ordinance is
more lenient than the lighting ordinances that are successfully being used in many communities
throughout the United States.
The term lighting source needs to be defined. Does a lighting source mean a single bulb or a
fixture? If it is a fixture, a multiple 45 watt incandescent light bulb would be covered by the
regulations. This means most homes in Ames would be covered. How will this be
administered?
A lighting source means a single bulb. Therefore, a fixture with multiple 45-watt incandescent
light bulbs would be exempt from the requirements of this ordinance.
It should be noted that implementing these guidelines for parking lots will require more poles
and more expensive fixtures.
This ordinance regulates the percentage of light reaching the ground at a distance greater than
four times the mounting height of the fixture. Normally, the reduction in glare provided by full-
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cutoff fixtures will more than compensate for any slight reduction in lighting uniformity caused
by the use of full-cutoff fixtures. If need be, higher poles can be used instead of increasing the
number of poles. While it is true that high efficiency full-cutoff light fixtures with good optical
control are sometimes a little more expensive than non-cutoff fixtures, the reduced energy and
maintenance costs of using the higher efficiency fixtures will quickly pay for any added initial
cost.
The development of lighting plans does contain a cost. The cost for these plans are built into
the cost of the fixtures. While these plans are commonly conducted for large projects, it could
be more difficult on small projects. With small lighting projects, it may be very difficult to get a
professional's assistance. If professionals are too busy on large projects, will a remodeling or
small expansion be delayed until a lighting report is done?
All lighting manufacturers that we know of have professional staff who will provide the needed
lighting design assistance for small projects in a very timely fashion and at no additional cost.
For small projects, professional services will not be needed beyond that normally provided by
your local electrical contractor.
The light trespass standards of 0.1 footcandles for non-exempt fixtures will be impossible to
enforce in residential areas. Studies have shown that lighting during a full moon is between
0.01 and 0.1 footcandles. Excluding light trespass at a figure slightly brighter than moonlight
seems too restrictive.
The light trespass standards in the proposed ordinance refer to illumination in the vertical plane,
and this is a way to quantitatively measure glare and light trespass with a simple illuminance
meter without the need for a more expensive and difficult-to-use luminance meter. The
maximum illumination in the horizontal plane provided by a full moon is no greater than 0.01
footcandles (IESNA Lighting Handbook, 8th Edition, 1993, p. 9). Enforcement in residential
areas will largely depend upon complaints from neighbors.
Who will be responsible for checking that all homes and businesses have shielding devices for
light fixtures near property lines?
The main focus of the lighting code will be to ensure that attractive, efficient, high-quality
lighting is installed in the first place, more so than to check on lighting after it is installed.
Shielding is often an integral part of high-quality lighting. We expect that for any new
installations, shielding as well as illuminance levels will be included in the lighting plans that
are submitted to the City Planning and Housing Department, making further checking
unnecessary.
After-installation enforcement will depend largely on complaints from residents. Like traveling
over the speed limit, only the worst offenders will be caught.
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Who determines if a light is nonessential? Most exterior lighting has the primary essential
purpose of providing security which is essential.
Sign lighting is generally not regarded as being security lighting. Thus it could be considered
"nonessential" in this sense. Some other types of lighting, such as lighting of apartment
buildings and parking lots, would be considered security lighting and could be left on all night.
However, such lighting would be required to meet the requirements of the Code regarding glare,
uplight, and light trespass.
Most businesses have signs on their buildings. The proposed regulations would prohibit
lighting these signs when a business is not open. A business, if it wants, should be able to
promote its location. Customers driving by the site, such as visitors, may return the following
day. Many Ames businesses leave signs attached to their building on after business hours. Why
is this change necessary? Have there been a number of complaints about these signs?
Illuminated signs are a significant contributor to urban skyglow, and light trespass when the
sign is near a residential area. Since there is little traffic after midnight, we would suggest that
the ordinance be changed to allow businesses that are closed to have their signs illuminated
until midnight.
The low level activity parking lot maximum lighting levels are too low according to local
electrical contractors. The 1.6 fc should be increased to 3.5 fc.
We see no reason to deviate from the IESNA recommended practice on this item. All average
initial horizontal illuminance levels in the proposed ordinance are twice the average maintained
horizontal illuminance levels recommended by the IESNA. We feel that allowing low activity
parking lots to be illuminated at over four times the IESNA recommended level is overkill,
particularly when one considers that many low activity level parking lots are located .in
residential neighborhoods (schools, churches, neighborhood shopping, etc.).
Nancy Clanton, a lighting engineer in Boulder, Colorado, sees little if any need for any parking
lot lighting to have an average horizontal illuminance level over 3 fc. Aside from that, there is
some flexibility in determining whether a particular parking lot might be considered to be a low
or medium activity level lot.
Requiring all outdoor advertising signs to be top mounted should be reconsidered. Off-premise
signs (billboards) are already required to be top mounted. On-premise signs should be allowed
latitude. Some establishments use smaller monument signs. Bottom lighting may be more
appropriate for these signs and it should be allowed.
We agree. However, it is important that with any approved monument sign lighting, monument
lighting, or building accent lighting that the light be efficiently directed so that at least 90% of
the light is directed at the monument sign, monument, or building facade.
Flag lighting is harder to control because the fixture is nearly always a considerable distance
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frbm-the flag, and the flag itself is a moving target. We would suggest that flag lighting should
be dealt with mainly by limiting total brightness of the lights directed toward the flag.
Shielding would also provide a small degree of control and could help eliminate sideways glare.
In grandfathering nonconforming lighting, businesses should be able to replace a fixture with
the same fixture. For example, if a light pole needs a new fixture in a parking lot, the
installation of a different fixture may cause an uneven lighting pattern.
We would suggest that the grandfathering clause would apply unless more than 50% of the light
fixtures of a like kind are replaced.
Personal safety is a subjective issue. A large, strong person may feel very safe in a low light
condition. That same situation for a small, frail individual could cause high anxiety. Light
translates into safety in the eye of beholder. Service providers with extended hours and
particularly those open 24 hours, know what level of light best serves their customers. The
convenience store industry does not support the maximum lighting guidelines as outlined in the
proposed ordinance. Their opposition is not related to advertising, rather it stems from a
desire to meet customer needs.
The IESNA is clear on this matter: no more than 20 footcandles are needed for service
station/convenience store pump islands in areas with dark surroundings, and no more than 30
footcandles are needed for pump islands with bright surroundings. These recommendations
fully take into account the safety and security issues mentioned above. The proposed ordinance
is allowing twice the IESNA recommended level. Furthermore, glare becomes a significant
issue with the very bright metal halide light sources that are employed in canopy lighting.
These light fixtures should be fully recessed into the canopy and/or a skirt around the edge of
canopy should block direct glare from reaching the roadway and adjacent properties.
As has been mentioned, a number of different convenience store chains have recently increased
their canopy light levels. It also seems that those that are raising light levels seem to have
chosen to do so to varying degrees. If there is clear understanding about the optimal levels of
lighting beneath canopies, then why is there so much variance in the new higher light levels?
Specifically, if one can agree that the light levels at Casey's at Lincoln Way & Walnut (55 — 60
fc) are high enough for security purposes, and if the lighting is not being used for advertising,
then what is the point of lighting the canopies at some other stores to levels as high as 90 — 100
fc?
A distinction also needs to be made between customers' feeling safe and actually being safe.
We have mentioned before that, in our view, excessive lighting beneath a canopy can reduce
customers' ability to see objects, people, etc. outside the canopy. This could make them more
vulnerable, despite their (perhaps) feeling safer under such bright lights.
Finally, concern about the brightness and intensity of convenience store lighting within Ames
was one of the main reasons why the City convened the Outdoor Lighting Task Force in the
first place. We need to deal with this issue somehow. Otherwise, the problems of glare, light
trespass, and overlighting will only get worse, as they have during the past few years.
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