6.3, 6.4 .-Q *
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ITEMS 6.3. & 6.4.
Wy of � MEMORANDUM
ElkRiver TO: Planning Commission
FROM: Scott Harlicker, Planning Assistant
DATE: November 26, 1996 If—
SUBJECT: American Portable Telecom Request
for Rezoning and Conditional Use
Permit, Public Hearing Case No.'s
ZC 96-20 and CU 96-26
Request
American Portable Telecom is requesting a zone change to rezone certain
property to Antenna Overlay District (AT) and conditional use permit for a
wireless communication antenna tower and equipment buildings.
Location
IIIThe property being utilized is located on the east side of County Road 13 that
currently contains Industrial Hardfacing's light manufacturing facility; PID #
75-135-2315
Zoning/Land Use
I1 (Light Industrial) / LI (Light Industrial)
Attachments
• Location map
• Zoning map
• Site plan
• Elevations
• Letter from Cellular Realty Advisors, Inc. dated October 29, 1996
Background
American Portable Telecom is proposing to lease an area approximately 50' by
50' in order to construct a 165 foot tall self supporting lattice tower on which
they will mount 9 directional antennas.
III
13065 Orono Parkway • P.O. Box 490 • Elk River, MN 55330 • (612) 441-7420 • Fax: (612) 441-7425
Memo to the Planning Commission Page 2
ZC 96-20 & CU 96-26
November 26, 1996
• The area the applicant plans on leasing is part of a 5 acre lot and is located 32
feet to the east of the existing building. The area is level and contains a 16"
diameter oak that will have to be removed in order to place the tower in the
proposed location.
The adjacent land uses include light industrial manufacturing, single family
residential and undeveloped residentially zoned land.
The site will be serviced by the existing 12' drive on the east side of the building.
There are 4 piles of scrap steel on the side of the drive between the drive and
the proposed location of the tower. These will have to be removed in order to
provide adequate access to the tower.
In order to better manage the potential proliferation of antennas in the city,
cellular towers should be capable of being used by other cellular providers. This
pole should be designed so that it can accommodate additional antennas for use
by other cellular companies.
Overview
• In order to construct the proposed tower and antennas, a rezoning of the
property to AT is required. This overlay district was established to manage the
proliferation of antenna towers and to insure their proper placement regarding
health, safety and welfare of the community. This overlay district does not
change the underlying I1 zoning district, all the uses allowed and the
dimensional regulations in the I1 zoning district will continue to be allowed on
land zoned AT.
In considering a rezoning request of this nature, consideration should be given
to the existing conditions within the area directly and indirectly affected by the
proposed rezoning as well as the compatibility with surrounding land uses.
The rezoning request should not adversely impact and would be compatible with
the zoning and current use of the property which is under consideration for
rezoning. However, the property is surrounded by single family homes and
properties that are zoned residential. The applicant should explain how the
proposed rezoning will be compatible with the adjacent land uses and zoning.
To address the issue of compatibility consideration should be given to
constructing a mono pole and painting it a color that will blend in with the
background.
•
s:\planning\scott\cu96-26.doc
Memo to the Planning Commission Page 3
ZC 96-20 & CU 96-26
November 26, 1996
• The applicant should provide information to support their assertion that an
antenna is needed in this location and how it will fit in with their long range
coverage plan for this area. They should also show why they could not colocate
on the recently approved AT&T tower to the south.
Recommendation
It is recommended that the Planning Commission have the applicant provide
additional information to support their assertion that the tower is necessary in
this location, how it will fit in with their long range plans, that it is compatible
with the adjacent single family residential zone, including color and design, and
is deigned so that it can accommodate additional antennas before making a
determination on this rezoning.
Conditional use Permit
The application was compared to the performance standards relating to the
Antenna Tower Overlay district.
1. The applicant should provide a letter from the manufacturer of the tower
explaining why there is no danger of the pole collapsing on to adjacent
property.
2. There is only one tower proposed for this lot and the lot exceeds the one
acre minimum lot size requirement.
3. The height of the proposed tower is 165 feet and does not exceed the 240
foot maximum height allowed in the zoning code. Because the proposed
height of the tower does not exceed 200 feet, the applicant is not required
to file with the F.A.A. for authorization. However, the tower requires
F.C.C. approval and the applicant should demonstrate that the tower has
met federal requirements prior to the issuance of a building permit.
4. No portion of the tower, support or related equipment extends across any
right-of-way, property line, public street or sidewalk; the pole and the
equipment buildings comply with setback requirements.
5. The applicant should demonstrate that the tower will be designed to
comply with wind loading factor as prescribed in the Uniform Building
Code, will comply with local electrical regulations and be grounded
against lightning strikes.
•
s:\planning\scott\cu96-26.doc
Memo to the Planning Commission Page 4
ZC 96-20 & CU 96-26
November 26, 1996
• 6. In order to discourage climbing the applicant is proposing an 8 foot high
fence surround the site; the fence will be topped with barb wire.
7. The applicant should demonstrate that based on topography of the site,
surrounding structures and vegetation and the design of the tower, that
off-site impacts such as lighting, electrical interference, visual impacts
and safety issues will be minimal.
Recommendation
It is recommended that the Planning Commission have the applicant provide the
following additional information before making a determination:
1. A letter from the manufacturer of the tower explaining why there is no
danger of the pole collapsing on to adjacent property.
2. The applicant should demonstrate that the tower will be designed to
comply with wind loading factor as prescribed in the Uniform Building
Code, will comply with local electrical regulations and be grounded
against lightning strikes.
• 3. The applicant should demonstrate that based on topography of the site,
surrounding structures and vegetation and the design of the tower, that
off-site impacts such as lighting, electrical interference, visual impacts
and safety issues will be minimal.
•
s:\planning\scott\cu96-26.doc
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• AT&T WIRELESS SERVICES
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CELLULAR Bloomington,
"Street,Suite 19
Bloomington,MN 55425
(612) 858-0000
(612) 854-4105 Fax
• REALTY
ADVISORS, INC.
29 October 1996
Mr. Scott Harlicker, Planning Assistant
City of Elk River
13065 Orono Parkway
Elk River, MN 55330
RE: Application for Conditional Use Permit and Re-Zoning Application
Proposed PCS Wireless Telephone Tower Facility
by American Portable Telecom(APT)
for 18489 Twin Lakes Road
Dear Mr. Harlicker:
This letter accompanies an application for a Conditional Use Permit and a request for a re-zone of a
site which will allow the location of a PCS wireless telephone antenna and self support lattice tower
on the property owned by Mr. And Mrs. Deschenes. I have been authorized by APT to act as their
representative for planning and zoning matters.
APT is a subsidiary of Telephone and Data Systems, Inc. (TDS). TDS is a Chicago-based
telecommunications company which provides cellular telephone, local telephone and radio paging
• services to more than 1.9 million customers in 37 states and the District of Columbia through its
subsidiaries, United States Cellular Corporation, TDS Telecommunications Corporation and
American Paging, Inc. APT is the 581 largest PCS license holder in the United States in terms of
population equivalents. Last year APT was granted a license by the Federal Communications
Commission to operate a PCS Wireless Phone System in the Twin City market area and five other
major markets in the United States. PCS is one of the newest emerging low-power wireless
technologies that will compete with the cellular and local phone service. PCS will look, sound and
work better than traditional cellular and will also have the advantage of being able to provide
paging, fleet dispatch data and video transmission all with one portable handheld phone. PCS
wireless is digital and can handle more calls per channel than traditional cellular and transmits at
lower watts.
USE OF EXISITING SITE AND SURROUNDING AREAS
The site is currently known as Industrial Hardfacing, Inc.. The site is zoned residential but is
currently being utilized for an industrial use. The 165 foot tower is located near the building and is
no less than 150 from any property line. The code requires the tower to either be setback from the
property line for 100% of the tower height, or the code allows a letter from a qualified engineer
confirming the typical "fall zone" of the tower. Please see typical "fall zone" letter in application
package.
PROPOSED USE
APT is proposing to construct a 50 meter (approximately 165 foot) steel self supporting lattice
tower. There will be up to nine directional panel antennas (77" high x 6" wide x 1.5" deep) which
operates within the 1.9 GHz to 2.2 GHz radio frequency range. Unmanned prefabricated
equipment cabinets measuring approximately 5' high x 3' wide x 3' deep will be located near the
• base of the tower. Typically these weather-proof, self-contained equipment cabinets are connected
to the antennas by 1 5/8' cable (each antenna requires one cable run). The communication
equipment requires 100 amp, 220 volt, single phase electrical service.
• ZONING AND CONDITIONAL USE REQUIREMENTS
The City of Elk River requires that for any site to be used for a communication tower, it must be first
zoned for the tower overlay district. In addition,towers are required to go through the conditional
use process. Attached you will find the application for the re-zone and the conditional use along
with copies of a survey of the site, the legal description for the site, the site plan and elevations of
the proposed tower, the necessary check for the applications, and a list of neighbors within 350 feet
of the site.
Please review the application and call me with any questions or concerns you may have. We would
like to be placed on the November 26 Planning Commission meeting agenda. Thank you for your
time.
Sincerely,
CELLULAR�IREALTY ADVISORS, INC.
440014 D. 20 ,C lmaa
Linda D. Whitman, APA
Zoning Manager
•
1701 E. 79`h Street, Suite 19
CELLULAR Bloomington, MN 55425
• (612) 858-0000
REALTY (612) 854-4105 Fax
ADVISORS, INC.
19 November 1996
Scott Harlicker, Planning Assistant
City of Elk River
13065 Orono Parkway
Elk River, MN 55330
Dear Scott:
As we discussed, I have gathered some of the information you requested. Attached you will find a letter
from Microfiect Engineers that discusses the"fall area"for self supporting towers. You will also find a
memo from our Radio Frequency Engineer,Steve Ramberg which discusses the reasons we need the
particular location on which we have applied for a conditional use permit. Steve has also provided a color
graphic showing coverage if we were on the water tower,the AT&T tower,and the requested location.
As you can see,there is a coverage gap in the two scenarios where we would attach antennas on an
existing structure.
You mentioned a concern for the oak tree located in the compound for the tower. We do not intend to
damage the tree in any way to erect this tower, You also had a concern for the 12'wide drive and the
possibility of our constructing a monopole rather than a lattice structure. I am unsure of the 12'wide drive
• and would ask that you call me to discuss this further. The tower is planned to be a lattice structure for
several reasons: It takes less time to obtain a lattice structure than a monopole structure. We are often
forced to use monopole structures in urban areas, partly because of lease area requirements and
sometimes because of perceived aesthetics, but this has generated a backlog of tower orders. We would
like to continue to plan on construction of the lattice tower but we are happy to discuss this with you
further.
Should you have any questions, please do not hesitate to call me at 858-0022. Thank you.
Sincerely,
CELLULAR REALTY ADVISORS, INC.
Zeacea V. 2Mitmao
Linda D. Whitman,APA, RLA
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'QED 10: 16FAX 503 316 2040 )MICROFLECT
l002
Amtr--,sek.4‘1,
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SUBJECT: Failure Modes and Design Criteria Information for Self-
Supperting and Guyed Towers
Design Criteria
Communications cowers designed by Microflect are typically sized in
accordance with the latest revision of the EIA/TTA 222 Standard
entitled "Structural Standards for Steel Antenna Towers and Antenna
Supporting Structures. " This standard has been approved by ANSI,
who has generated the standard for ''Minimum Design Loads for
Buildings and Other Structures" . This standard, which is the basis
for design loading for practically every building code and standard
in the country, has dealt with the design of lattice type
structures for a large number of years .
This standard is based on provisions of this nationally kncwn
specification that has a long history of reliability. At it' s core
root is it's first and foremost priority is to safeguard and
maintain the health and welfare of the public.
The standard dictates minimum wind loading the predominant loading
on a tower structure) for each county in the United States. It is
Microflect' s policy to use the wind loading listed in the latest
• ETA standard as a minimum loading unless the customer specifies a
larger value. Statistically, the wind speed _fisted in EIA-E has
been determined to be that wind which has an average reoccurrence
of 50 years (ie. the magnitude has a 2% chance of occurring in any
one year; . This wind is also a "fastest mile" wind which, by
definition, is the average velocity of a mile of wind passing a
fixed point. This standard "fastest mile" wind is customized with
height , exposure, and gust factors that apply to the particular
Thstallations.
The loads generated by this wind, along with weight of the tower
members and any ice being considered, are used to size members of
the tower. There is a minimum of a 25% safety factor required
under these conditions (ie. each and every member has a reserve
capacity which is 25% higher than the maximum load it will
experience during the extreme 50-year wind) . Besides magnitude of
the wind, the orientation to the tower is also critical. Some
directions are worse than others, depending on placement of
antennas, appurtenances, etc. To fail tower members the wind must
exceed all of our estimates for magnitude, duration, be at worst
orientation and overcome the factor of safety.
Failure Modes
Let us assume that a tower member force has exceeded all rational
design criteria and has becomed overloaded. The typical
•
PLANT ADDRESS TELECOMMUNICATIONS MAILING ADDRESS
35'5 25" Street SE Telephone (503) 363-9267 P.O. Box 12985
Colum ;'bonen R73C•2.1190 FAX (5C3) 353-4513 Sa em OR USA 97309-0985
FOLD 10: 1-_ FAX 503 316 2040 MICROFLcCT 4003
• consequence of the overloading is "local buckling" where a
relatively small portion of the member distorts and "kinks" the
steel . If this occurs, much of the loading is redistributed to
members with unused reserve capacity. The end result is a
localized distortion, but rarely a complete tower collapse. Of
course, any overstressed member should be replaced as soon as
possible.
Towers are made of many members . As stated, lead redistribution
enables the tower to sustain loads even in excess of extreme
magnitudes used in tower design. Also, towers are flexible
structures which react well to wind gust or earthquake shocks and
are typicality not damaged by intact loads. It takes some time for
the entire structure to "see" the effects of loading.
Microflect has no direct experience with tower failures . However,
from what evidence we have seen from other vendor' s experiences, I
can state that it is rare for a tower to fall in a radius larger
than it' s heicht, and that in most cases it will collapse in a
small confined area as it comes down upon itself . For guyed-cowers
this is especially true for structures with more than a single guy
radius circle.
Microflect communication towers have proven to be very reliable
products. In our 40 years of engineering and fabricating towers we
• have not had one tower fail due co overloading, even in the extreme
cases that wind speeds have exceeded design values. We use the
latest standards, wind speed =formation, and sophisticated
analytical tools to ensure that we maintain cur unblemished record
for quality. In good faith, I can confidently state that our
towers are the best engineered products available and the
probability of any type of failure is remote at best.
.r E Grassman, P.E.
chief Engineer
6/2/96
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APT
• AMERICAN PORTABLE TELECOM
A TDS COMPANY
1701 E.79th Street
Suite 19
Minneapolis,MN 55425
612-858-0000
Fax 612-851-9103 �
Date: 11/18/96
To: Chairperson,City of Elk River
From: Steve Ramberg,RF Engineer-American Portable Telecoh-,(
RE: Analysis of antenna sites within the city of Elk River
As the Radio Frequency engineer assigned to design and analyze a tower site for Elk River,I have performed
evaluations on several possible locations. The following is a list of those locations and subsequent analysis. Factors
weighed into each analysis include tower height,terrain,foliage and building density. Our objective is to provide
coverage within the City of Elk River and link with additional sites along Highway 10 and Highway 169 with a
• minimum number of towers. The frequency band which we have been granted license by the FCC limits our tower
height to 165' maximum and more towers than current cellular providers.With a tower under construction in the
town of Dayton tower placement in Elk River becpmes critical to insure contiguous coverage between cell sites.
Sufficient coverage can be defined as enough transmitted signal from a tower to initiate,sustain or receive a call to or
from a mobile telephone. Coverage holes can be defined as absence of transmitted signal within a given area,which
results in dropped calls or failure to initiate or receive a call from a mobile telephone.
1. AT&T Tower-Use of this tower will provide sufficient coverage along Highway 10 between Elk River and
Dayton,however analysis determined poor coverage in the city of Elk River and coverage holes on Highway 169
between Elk River and Zimmerman on account of terrain problems north of Elk River.Additional towers in Elk
River and along Highways 10 and 169 would be required to fill in coverage holes.
2. Elk River Water Towers-tower height is the primary difficulty. In order to minimize the number of towers 165
feet is required. Due to insufficient height on the water towers we are unable to overcome terrain height to the
north or link with our tower in Dayton. Additional towers in Elk River and along Highways 10 and 169 would
be required to fill in coverage holes.
The location we selected enables APT to provide high quality coverage in the city of Elk River,overcome terrain
issues north along Highway 169 and link with our tower in Dayton. Our expansion plan for the city of Elk River
involves addition of antennas on the existing tower. No plans exist to add additional towers.
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