Memorandum
To:
From:
Date:
Re:
Jefferson County Planning
and Zoning Department
Long Range Planning Section
303-271-8700
Russ Clark
Dennis Dempsey
July 21, 2015
Case #15-113378RZ
Project Name: Wind Turbine Rezoning
Location: 8354 Armadillo Trail.
Proposal: Rezone from Suburban Residential-Two to possibly an Agricultural-One zone
district to allow for a 90 feet in height wind power turbine. The subject property
contains about 5.3 acres.
Community Plan Recommendations
The subject property is located within an area covered by the Evergreen Community
Plan. It is located outside of an activity center and recommended for residential
development for up to 1 dwelling unit per 10 to 35 acres. The goals and policies
pertaining to land use and utilities found in the County’s Comprehensive Master Plan
should also be considered.
General Comments
 The subject property is currently zoned Suburban-Residential-Two (SR-2). The
applicant proposes to rezone the subject property to a Planned Development zone
district.
 According to Section 8 in the County’s Zoning Resolution, an energy conversion
system (ECS) requires a permit from Planning and Zoning.
 An ECS is allowed as a permitted use in Agricultural-One and SR-2 zone district,
however the height would be limited to the height of the principle structure or 35’.
 If the applicant wishes to rezone to a PD, the height of the ECS would be limited to
the described in the ODP Written Restrictions.
 The subject property is a heavily treed, 5.29 acre lot, located at an elevation of
about 8,240’ above sea level. It appears that the property slopes from east to west
and it may contain slopes greater than 20 to 30%.
 The subject property is considered within a Highly Visible area from Jefferson County
Highway 73. As this site is highly visible and the equipment sits on a 20 to 30%
slope, special care should be given to minimizing the visual obtrusiveness of the
equipment by using stealth technology, burying lines, coloring equipment, and/or
screening to blend with the background. (CMP p. 54)
 Development within highly visible area should apply the following minimal
disturbance techniques:
a. Structures should be sited with sensitivity.
b. Access roads should be shared wherever possible.
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c. Grading for roads and structures should be kept to a minimum. Cut and fill
slopes should be sensitively designed to blend with the natural terrain, using
methods such as revegetation, berming, rock staining, etc.
d. Rock outcroppings, unique vegetation, historic structures, meadows, and
ridgelines should be conserved.
e. The mass, materials, and colors of buildings should complement the natural
landscape.
f. Signage and lighting should comply with the Plan’s Design Guidelines. (EP p. 54)
The ODP Written Restrictions should specify the details concerning the materials
used for the installation of the proposed wind turbine and accessory equipment
building. Equipment colors should be noted as well as the height and span of the
wind turbine. A visual simulation may be needed to get a sense of what a 90’ tall
wind turbine would look like from off-site and from Highway 73.
The County’s Comprehensive Master Plan does support and encourages the use of
alternative energy sources. (CMP p. 35) However, the visual impacts to the
neighboring community would be a major concern for the overall community’s
health, safety and welfare.
If possible, the wind turbine project should be integrated into the existing
community development pattern and prevailing topography. (CMP p. 37)
The Evergreen Community Plan’s Geologic Hazards map shows that the subject
property may be within a Moderate Risk Geologic Hazards area. This could be from
the soil being highly erodible or highly sensitive and may require further
investigation. The soil condition should be confirmed by the County Geologist in
order to determine if additional mitigation is needed.
The subject property is also considered within a Severe Wildfire Hazard area. A
defensible space should be created and maintained around each structure. (EP p.
15)
The subject property is within a High, Area 2, Wildlife Quality Area.
Access to the subject property is gained off of Armadillo Trail.
Public Facilities, Services and Utilities
 The CMP acknowledges that the technological, operational, maintenance and safety
constraints of utilities may impact the ability to mitigate impacts to the natural and
built environment.
 Utility lines should be places so they are sensitive to the environment.
 The utility provider should work with the neighborhood when planning for site
selection and facility design.
Visual Resources
 Development should be designed to integrate design techniques such as: color, line,
form, and texture, with the existing natural characteristics of the site.
 The sites natural screening capacity should be incorporated into the overall site
design.
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Techniques to reduce negative visual impacts should include:
a. The use of dark, receding colors;
b. Architecture which is low contrast and doesn’t dominate the site;
c. A low level of site disturbance and high level of natural screening; and
d. The use of shielded, downcast lighting to minimize glare and off-site light.
Design Guidelines
 Minimize visual intrusion of utility poles, towers and related structures.
a. Place utilities underground.
b. Locate in areas not prominent to public viewing.
c. Screen substations/pump-stations with:
- Intensive landscaping or earthforms; and /or other buildings.
 Minimize views of mechanical equipment (roof, wall, and ground mounted) from
residential uses, public rights-of way, or parks.
Non-commercial Energy Conversion Systems (ECS)
a. Intent: The purpose and intent of this Regulation is to establish guidelines for the
siting non-commercial ECS and associated equipment in an effort to allow for alternative
energy sources. The non-commercial ECS shall only provide power to the principal and
accessory uses of the property and shall not be for the generation of power for
commercial purposes. However, this provision shall not be interpreted to prohibit the
sale of excess power generated from the system back to the public utility. (orig. 4-20-10)
b. Wind Energy Conversion Systems (WECS) Performance standards: (orig. 4-20-10)
(1) Unless specifically permitted in Table AES-1, non-commercial WECS shall be building
mounted. (orig. 4-20-10;am. 3-26-13)
(2) The height of the building mounted WECS shall extend no further than 5 feet above
the structure to which it is mounted, or exceed the maximum height permitted in the
zone district, whichever is lower. (orig. 4-20-10)
(3) Free standing non-commercial WECS, where permitted, shall not exceed the
maximum height permitted in the zone district. (orig. 4-20-10) Building mounted noncommercial WECS shall be placed on a structure that either meets the minimum setback
requirements of the zone district, has gone through a process to legalize the existing
setbacks, or has been established as being legal non-conforming in regards to the
setbacks of the structure (orig. 4-20-10;am. 3-26-13)
(5) Free standing non-commercial WECS shall be constructed of a monopole or similar
design, and shall meet the minimum setback for the primary structure, or shall be
setback 1:1 times the height of the tower, whichever is greater. (orig. 4-20-10; am. 3-2613)
(6) Non-commercial WECS shall be painted a subdued earth-tone, white, or gray to mute
the visual impact of the system. (orig. 4-20-10)
(7) Applications for a non-commercial WECS shall include the make, model, picture and
manufacturer’s specification, including specifications of electromagnetic shielding,
filtering, or construction design so as to not cause electrical, radio frequency, television,
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and other communication signal interference, and noise decibels produced by the
system. (orig. 4-20-10)
ALTERNATIVE ENERGY SYSTEMS TABLE (Table AES-1)
Zone District
Non-commercial
WECS
Commercial
WECS
Non-commercial
SECS
1
P
1
P
P
P
P
P
P
1
P
P
P
P
P
Commercial
SECS
Residential
P
R-3 (Multifamily)
R-3A (Multifamily)
R-4 (Multifamily)
RC-1
C-1 (Convenience)
C-1 (Neighborhood)
P
1
P
1
P
1
P
1
P
1
P
C-1 (Community)
C-1 (Regional)
C-2
I-1
I-2
P
1
P
P
P
P
I-3
I-4
A-1
P
P
P
P
P
P
P
P
A-2
P
P
P
P
A-35
CD
M-C
P
P
P
P
P
P
P
P
P
P
PD*
P
P
P
1
P
P
1
P
P
P = Permitted (Use by Right – administrative review of alternative energy permit)
P1 = Non-commercial WECS shall be limited to building mounted facilities
PD*=WECS in Planned Developments will be reviewed and compared to the most similar standard zone district.
Blank = Rezoning Required
. 4-20-10
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