A.
All preliminary plats shall include documentation of a four-step
design process in determining the layout of proposed conservation
areas, house sites, streets and lot lines, as described below.
B.
Step 1: Delineation of conservation areas.
(1)
Conservation areas shall include all wetlands, one-hundred-year floodplains,
and slopes exceeding 20%, plus those parts of the remaining buildable
areas with the highest resource significance. In conventional subdivisions,
conservation areas may be located within individual lots. In conservation
subdivisions, conservation areas shall be located outside individual
lots, in common areas owned and maintained by a homeowners' association,
on areas donated to land trusts or to a level of government, or in
non-common open space.
(2)
In conservation subdivisions, the minimum percentage and acreage of required conservation areas shall be calculated by the applicant and submitted as part of the sketch plan (overlay sheet) or preliminary plat in accordance with the provisions of Chapter 275, Zoning.
(3)
Proposed conservation areas shall be designated using the existing conditions and site analysis map as a base map and complying with the Conservation Design Review Standards listed in § 235-41 of this chapter. The City's Map of Potential Conservation areas shall also be referenced and considered. Conservation areas/unbuildable shall be delineated, comprising floodplains, wetlands and slopes over 20%.
(4)
In delineating conservation areas, the applicant shall prioritize natural and cultural resources on the tract in terms of their highest to least suitabilities for inclusion in the proposed conservation subdivision in consultation with staff and in accordance with the conservation design review standards listed in § 235-41 of this chapter.
(5)
On the basis of those priorities and practical considerations given
to the tract's configuration, its context in relation to resource
areas on adjoining and neighboring properties, and the applicant's
subdivision objectives, conservation areas shall be delineated in
a manner clearly indicating their boundaries as well as the types
of resources included within them. Conservation areas shall comprise
at least 50% of the land area not occupied by street, drainage, or
utility rights-of-way, one-hundred-year floodplains, wetlands, or
slopes of 20% or more. In subdivisions where septic systems are to
be located outside of the lot lines, the conservancy area shall be
drawn to include sufficient areas of soil suitable for POWTS in close
proximity to the lots being served.
C.
Step 2: Location of house sites. Potential building pads shall be
tentatively located using the proposed conservation areas as a base
map as well as other relevant data on the existing conditions and
site analysis map such as topography and soils. House sites should
generally be located not closer than 75 feet to navigable bodies of
water and not closer than 50 feet to conservation areas, taking into
consideration the potential negative impacts of residential development
on such areas as well as the potential positive benefits of such locations
to provide attractive views and visual settings for residences.
D.
Step 3: Alignment of streets and trails. Upon designating the house
sites, a street plan shall be designed to provide vehicular access
to each house and bearing a logical relationship to topographic conditions.
Impacts of the street plan on proposed conservation areas shall be
minimized, particularly with respect to crossing environmentally sensitive
areas such as wetlands and traversing slopes exceeding 12%. Street
connections shall generally be encouraged to minimize the number of
new culs-de-sac to be maintained by the City and to facilitate access
to and from homes in different parts of the tract (and adjoining parcels).
E.
Step 4: Drawing in the lot lines. Upon completion of the preceding
three steps, lot lines are drawn as required to delineate the boundaries
of individual residential lots. Applicants shall be prepared to submit
four separate sketch maps indicating the findings of each step of
the design process, if so requested by the City Department of Community
Development.
A.
Prioritized list of resources to be conserved. The design of conservation
areas in any conservation subdivision shall incorporate the following
resources if they occur on the tract (listed in order of significance):
(1)
Stream channels, floodplains, wet soils, swales, springs, vernal
pools, and other lowland areas. Adjacent buffer areas of at least
75 feet from structures, streets, and other major improvements are
strongly encouraged. However, alongside navigable bodies of water,
there shall be a minimum seventy-five-foot setback for structures
and roads to ensure the protection of these sensitive natural features.
(2)
Areas where precipitation is most likely to recharge local groundwater
resources because of topographic and soil conditions affording high
rates of infiltration and percolation.
(3)
Significant natural areas of species listed as endangered, threatened,
or of special concern, such as those listed in the WDNR's "The
Wisconsin Natural Heritage Working List."
(4)
Moderate to steep slopes, particularly those adjoining watercourses
and ponds, where disturbance and resulting soil erosion and sedimentation
could be detrimental to water quality.
(5)
Healthy woodlands, particularly those performing important ecological
functions such as soil stabilization and protection of streams, wetlands
and wildlife habitats.
(6)
Hedgerows, groups of trees, large individual trees of botanic significance,
and other vegetational features representing the site's rural
past.
(7)
Historic structures and sites such as buildings older than 100 years,
stone walls, cellar holes, abandoned public roads, family cemeteries,
etc.
(8)
Visually prominent topographic features such as knolls, hilltops
and ridges, and scenic viewsheds as seen from public roads (particularly
those with historic features).
(9)
Existing trails connecting the tract to other locations in the City.
(10)
Class I, II, and III agricultural soils, as defined by the USDA
Natural Resource Conservation Service.
B.
Other conservation area design guidelines. The configuration of proposed
conservation areas set aside for common use in residential subdivisions
shall, to the fullest extent possible, comply with the following guidelines:
(1)
They shall be free of all structures except historic buildings, stone
walls, and structures related to conservation uses. The City may grant
approval of structures and improvements required for storm drainage,
sewage treatment and water supply within the conservation areas, provided
that such facilities would not be detrimental to said conservation
areas (and that the acreage of areas required for such uses is not
credited towards minimum conservation acreage requirements for the
tract, unless the land they occupy is appropriate for passive recreational
use). The City may also grant permission to construct modest buildings
for recreational uses, such as shelters for the use of ice skaters,
etc., provided they are located within unconstrained parts of the
conservation areas (i.e., not wetland, floodprone, or slopes greater
than 20%).
(2)
They shall generally not include parcels smaller than three acres,
have a length-to-width ratio of less than 4:1, or be less than 75
feet in width, except for such areas specifically designed as neighborhood
greens, playing fields or trail links.
(3)
They shall be directly accessible to the largest practicable number
of lots within the subdivision. Nonadjoining lots shall be provided
with safe and convenient pedestrian access to the conservation area.
(4)
They shall be suitable for active recreational uses to the extent
deemed necessary by the City without interfering with adjacent dwelling
units, parking, driveways, and roads.
(5)
They shall be interconnected wherever possible to provide a continuous
network of conservation areas within and adjoining the subdivision.
(6)
They shall provide buffers to adjoining farmland, parks, preserves
or other protected areas where possible and as approved by the City.
(7)
Except in those cases where part of the conservation area is located
within private house lots, they shall provide for pedestrian pathways
for use by the residents of the subdivision. Consideration shall be
given to providing for public access on such trails if they are linked
to other publicly accessible pathway systems within the City. Provisions
should be made for access to the conservation areas, as required for
land management and emergency purposes.
(8)
They may be undivided by public or private streets, except where
necessary for proper traffic circulation.
(9)
They shall be suitably landscaped either by retaining existing natural
cover and wooded areas and/or according to a landscaping plan to protect
conservation resources. Such landscaping shall emphasize the planting
of native trees, shrubs and wildflowers.
(10)
They shall be made subject to such agreement with the City and
such conservation easements duly recorded in the office of the County
Register of Deeds as may be required by the City for the purpose of
preserving the common open space for such uses.
C.
The proposed conservation design shall be consistent with the City's
Comprehensive Plan.
