A.
Compliance with statutes. In laying out a subdivision, the owner shall conform to the provisions of Ch. 236, Wis. Stats., and all applicable City regulations. In all cases where the requirements of this chapter are different from the requirements of Ch. 236, Wis. Stats., the more restrictive provision shall apply.
B.
Dedication. The subdivider shall dedicate land and improve streets as provided in this article and § 472-26. Streets shall be located with due regard for topographical conditions, natural features, existing and proposed streets, utilities and land uses and public convenience and safety. Streets shall conform to Official Maps adopted by the Common Council. The subdivision, certified survey parcel or land division shall be so designed as to provide each lot with satisfactory access to a public street or road.
C.
Compliance with Comprehensive Plan and ordinances.
(1)
The arrangement, character, features and layout of land divisions
in the City of Colby shall be designed to comply with the standards
of this chapter, the Comprehensive Plan, the Official Map and/or any
comprehensive utility plans or other planning documents which may
pertain to the standards of design for land divisions and which have
been adopted by the Common Council. Where no such planning documents
have been adopted, subdivisions shall be designed according to engineering
and planning standards approved by the City Engineer and applied so
as to properly relate the proposed development with adjacent development,
the topography, natural features, public safety and convenience and
the most advantageous development of undeveloped adjacent lands. In
the absence of a street being shown on the Official Map, streets shall
be provided in locations determined necessary by the City Engineer
and to the right-of-way widths required in this article for the classification
of street required.
(2)
The arrangement, character, extent, width, grade and location of
all streets shall conform to City Master Plans, the Official Map,
and to this chapter and other City planning documents and shall be
considered in their relation to: existing and planned streets, reasonable
circulation of traffic, topographical conditions, runoff of stormwater,
public convenience and safety and in their appropriate relation to
the proposed uses of the land to be served by such streets.
(3)
The arrangement of streets in new subdivisions shall make provision
for the appropriate continuation at the same or greater width of the
existing streets in adjoining areas.
D.
Areas not covered by Official Map or plan. In areas not covered by
an Official Map or a City Comprehensive Plan, the layout of streets
shall conform to the plan for the most advantageous development of
adjoining areas of the neighborhood. Streets shall be designed and
located in relation to existing and officially planned streets, topography
and natural terrain, streams and lakes and existing tree growth, public
convenience and safety and in their appropriate relation to the proposed
use of the land to be served by such streets.
E.
Proposed streets. Proposed streets shall extend to the boundary lines
of the tract being subdivided unless prevented by topography or other
physical conditions or unless, in the opinion of the Common Council,
such extension is not necessary or desirable for the coordination
of the layout of the subdivision or land division or for the advantageous
development of the adjacent tracts.
F.
Streets classifications. Streets shall be required and classified
by the City Engineer in accordance with the City's Comprehensive Plan
and, where not identified in said plan, in accordance with sound engineering
standards, into the classifications indicated below:
(1)
Arterial streets. Arterial streets shall be arranged to provide through
traffic for a heavy volume of vehicles.
(2)
Collector streets. Collector streets shall be arranged so as to provide
ready collection of traffic from individual areas and conveyance of
this traffic to the major street and highway system and shall be properly
related to special traffic generators such as schools, churches and
shopping centers and other concentrations of population and to the
major streets into which they feed.
(3)
Local/Minor streets. Local streets shall be arranged to conform to
the topography, to discourage use by through traffic, to permit the
design of efficient storm and sanitary sewerage systems and to require
the minimum street area necessary to provide safe and convenient access
to abutting property.
(4)
Alleys. Alleys shall be located at rear property lines, shall discourage
through traffic, shall serve less than 50 vehicles/day and shall be
intended to provide access to off-street loading and service areas
and not primary access to parcels.
G.
Reserve strips. Reserve strips shall not be provided on any plat
to control access to streets or alleys, except where control of such
strips is placed with the City under conditions approved by the Common
Council.
H.
Extraterritorial streets. Streets located in the extraterritorial
plat jurisdiction of the City shall provide for the dedication of
the minimum widths of right-of-way in accordance with the standards
adopted by the pertinent town government in which the project is located.
Other streets within the extraterritorial plat jurisdiction of the
City shall meet or exceed the town road standards of § 82.50,
Wis. Stats.
I.
Alleys; cul-de-sac streets.
(1)
Commercial and industrial. Alleys may be provided in commercial and
industrial districts. The width of the right-of-way for residential
alleys shall be not less than 24 feet; and the width of the right-of-way
for commercial and industrial alleys shall be not less than 32 feet.
Alleys shall be constructed according to base and surfacing requirements
for streets.
(2)
Residential. Alleys shall not be approved in residential areas unless
necessary because of topography or other exceptional circumstances.
(3)
Dead ends. Dead-end alleys are prohibited except under very unusual
circumstances, and crooked and "T" alleys shall be discouraged. Temporary
dead-end streets shall not be over 600 feet in total length, shall
provide for an eventual intersection spacing meeting the requirements
of this chapter and shall provide for temporary culs-de-sac or turnarounds
as approved by the City Engineer.
(4)
Permanent dead-end streets; cul-de-sac streets. Permanent dead-end
streets or culs-de-sac shall not be longer than 600 feet, shall have
a minimum width of 60 feet and terminate with a turnaround having
minimum radii of 30 feet for roadway and 40 feet for a street line.
J.
Continuation. Streets shall be laid out to provide for possible continuation
wherever topographic and other physical conditions permit. The use
of culs-de-sac shall be held to a minimum, and permanently dead-ended
streets shall be prohibited. Provisions shall be made so that all
proposed streets shall have a direct connection with, or be continuous
and in line with, existing, planned or platted streets with which
they are to connect. Proposed streets shall be extended to the boundary
lines of the tract to be subdivided, unless prevented by topography
or other physical conditions, or unless in the opinion of the Common
Council, upon the recommendation of the Planning Committee, such extension
is not necessary or desirable for the coordination of the layout of
the subdivision with existing layout or the most advantageous future
development of adjacent tracts.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
K.
Minor streets. Minor streets shall be so laid out so as to discourage
their use by through traffic.
L.
Frontage roads. Where a land division abuts or contains an existing
or proposed arterial highway, or railroad right-of-way, the subdivider
shall provide a frontage road, platted access restriction along the
property contiguous to such highway or such other treatment as may
be determined necessary by the City Engineer to ensure safe, efficient
traffic flow and adequate protection of residential properties.
M.
Private streets. Private streets shall not be approved nor shall
public improvements be approved for any private street; all streets
shall be dedicated for public use.
N.
Width; radii of curvature; grades. All street right-of-way widths,
radii of curvature and grades shall conform to the following requirements:
|
Street Type
|
Right-of-Way Minimum Width
(feet)
|
Minimum Radius of Curvature
(feet)
|
Maximum Grade
|
|---|---|---|---|
|
Arterial or Highway
|
120
|
300
|
6%
|
|
Collector
|
80
|
200
|
7%
|
|
Minor
|
66
|
100
|
10%
|
O.
Visibility. Streets shall afford maximum visibility and safety for
motorist, bicycle and pedestrian use and shall intersect at right
angles, where practicable. A minimum sight distance with clear visibility,
measured along the center line, shall be provided of at least 500
feet on major thoroughfares, 200 feet on collector-distributor streets
and 150 feet on all other streets.
P.
Tangents. A tangent at least 100 feet long shall be required between
reverse curves on arterial and collector streets.
Q.
Vertical curves. All changes in street grades for arterials and changes
in street grades for collector and local streets where the algebraic
difference in the rate of grade exceeds 1% shall be connected by vertical
curves. The minimum length, in feet, of the vertical curve shall be
the product of the "K" value for the associated street design speed
times the algebraic difference in the rate of grade.
R.
Half streets. Half streets shall not be platted unless necessary
to provide the full width of an existing street platted to half width.
All newly platted streets shall be platted to the required full width.
Where a half street exists adjacent to a proposed land division, the
subdivider shall endeavor to acquire and dedicate the remaining half
street.
S.
Intersections.
(1)
Angle of intersect. Streets shall intersect each other at as nearly
right angles as topography and other limiting factors of good design
permit. The curved street shall intersect another street with not
less than 40 feet of tangent right-of-way between the end of curvature
and the right-of-way of the street being intersected.
(2)
Number of streets converging. The number of streets converging at
one intersection shall be reduced to a minimum, preferably not more
than two. Intersections of local streets shall be at least 125 feet
from each other.
(3)
Number of intersections along arterial streets. The number of intersections
along arterial streets shall be held to a minimum. Wherever practicable,
the distance between such intersections shall be not less than 1,200
feet, unless otherwise determined by the City Engineer to provide
better safety.
(4)
Local street spacing. Local streets and frontage roads intersecting
with other local streets shall be spaced no closer than 300 feet between
center lines and spaced no closer than 800 feet between center lines
on collector streets, unless otherwise approved by the Planning Committee.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
(5)
Property lines at street intersections. Property lines at street
intersections shall be rounded with a minimum radius of 15 feet; except
that with all intersections with arterial and collector streets the
radius shall be increased to 25 feet or of a greater radius when required
by the City Engineer.
(6)
Local streets. Local streets shall not necessarily continue across
arterial or collector streets, but if the center lines of such local
streets approach the major streets from opposite sides within 150
feet of each other, measured along the center line of the arterial
or collector streets, then the location shall be so adjusted that
the adjoinment across the major or collector street is continuous
and a jog is avoided.
(7)
Additional sight easements. At any intersection determined by the
City Engineer, restricted development easements or additional street
right-of-way shall be platted to provide for adequate sight distances
in every direction of travel. At a minimum, the subdivider shall grade,
clear or otherwise provide for an unobstructed sight triangle at all
intersections incorporating the area within a triangle formed by the
intersection of the street right-of-way lines and a point on each
right-of-way line being not less than 25 feet from the intersection
point.
T.
Street names.
(1)
Duplication of existing street names by similar word, spelling or
sound shall not be permitted.
(2)
Where a street maintains the same general direction except for curvilinear
changes for short distances, the same name shall continue for the
entire length of the street. House numbering difficulties shall be
considered the determining factor in considering whether a change
of name is necessary due to curvilinear changes.
(3)
A street name shall be changed when required to conform to the proposed
or existing house numbering base.
(4)
A name which is assigned to a street which is not presently a through
street, due to intervening land over which the street extension is
planned, shall be continued for the separate portions of the planned
through street.
(5)
The following designations shall be used only in the situations indicated:
(a)
"Boulevard": a street with a divided pavement, either existing
or planned. If the divided pavement ends but the street continues,
the same street name and suffix shall continue.
(b)
"Lane": to be limited to a street, one block long, not ending
in a cul-de-sac.
(c)
"Circle": to be limited to a cul-de-sac of nine lots or more.
(d)
"Court": to be limited to a cul-de-sac of eight lots or less.
(e)
"Parkway": to be limited to a street abutting a park or greenway
or creek.
(6)
The maximum number of street names at one intersection shall be three.
(7)
Street names shall be assigned to avoid intersections which have
the same exact street names.
(8)
The name of any projection of a street shall remain unchanged even
if the projection terminates in a cul-de-sac.
(9)
The changing of a street name that does not duplicate an existing
street name shall only be approved where such change will eliminate
conflicts with other provisions of this subsection.
(10)
Service roads and highways served by them shall have the same
street name and designation.
(11)
Approval of street names on a preliminary plat will not reserve
the names, nor shall the City be required to accept such names at
the time of final platting.
(12)
A minimum number of letters is desirable in a street name. The
maximum number of letters, not including the prefix or suffix, shall
not exceed 12.
U.
Limited-access highway and railroad right-of-way treatment. Whenever
the proposed subdivision contains or is adjacent to a limited-access
highway, arterial street or railroad right-of-way, the design shall
provide the following treatment:
(1)
Subdivision lots. When lots within the proposed subdivision back
upon the right-of-way of an existing or proposed limited-access highway
or a railroad, a planting strip at least 30 feet in depth shall be
provided adjacent to the highway or railroad in addition to the normal
lot depth. This strip shall be part of the platted lots but shall
have the following restriction lettered on the face of the plat: "This
strip reserved for the planting of trees and shrubs; the building
of structures hereon prohibited."
(2)
Commercial and industrial districts. Commercial and industrial districts
shall have provided, on each side of the limited-access highway, arterial
street or railroad, streets approximately parallel to and at a suitable
distance from such highway or railroad for the appropriate use of
the land between such streets and highway or railroad, but not less
than 150 feet.
(3)
Streets parallel to a limited-access highway. Streets parallel to
a limited-access highway or railroad right-of-way, when intersecting
a major street and highway or collector street which crosses said
railroad or highway, shall be located at a minimum distance of 250
feet from said highway or railroad right-of-way. Such distance, where
desirable and practicable, shall be determined with due consideration
of the minimum distance required for the future separation of grades
by means of appropriate approach gradients.
(4)
Minor streets. Minor streets immediately adjacent and parallel to
railroad rights-of-way shall be avoided, and location of minor streets
immediately adjacent to arterial streets and highways and to railroad
rights-of-way shall be avoided in residential areas.
A.
General requirements.
(1)
Construction standards. All roadway construction and materials used shall be performed in accordance with the construction methods as listed in the appropriate sections of the State of Wisconsin Department of Transportation Standard Specifications for Road and Bridge Construction and its supplements and this chapter, whichever is more restrictive. The design requirements of this section and § 472-40 shall be applicable to all streets and roads that are to be dedicated to the City, regardless of whether such streets or roads are part of a new subdivision or land division. Design requirements for the pavement shall be adequate for the zoning classification of the area served by the subject street. A street which divides areas with different zoning classifications shall be constructed in accordance with the requirements of the area requiring the higher-quality pavement. Any variation of this must have prior approval of the City Engineer. Combination concrete curb and gutter is required on all streets when so directed by the City Engineer. (Refer to § 472-27, describing requirements for curbs and gutters.) A copy of all design assumptions and computations on which the proposed design is based shall be submitted to the City Engineer.
(2)
Project costs. All roadway surveys, dedications, plans and specifications
and construction will be at the expense of the applicant or applicants.
This includes any expense incurred by the City in the preparation
of plans and review and inspection of plans and construction.
(3)
Preliminary consultation. Prior to the design, preparation and construction
of any roadway to be dedicated to the City of Colby, the applicant
shall notify the City Engineer. An on-site meeting will then be arranged
to be attended by the City Engineer and the applicant. Plans must
be provided in order for the City Engineer to check the design and
the drainage.
(4)
Material slips. Copies of material slips for all materials furnished
for the road construction projects shall be delivered to the City
before the City approves the final construction.
(5)
Required inspections. Prior to the commencement of any street construction,
the subdivider shall notify the City Engineer, at least three workdays
in advance, as to the nature of the work being done. The City Engineer
shall be contacted for required inspections during the following phases
of construction: a) subbase grading; b) crushed aggregate base course;
and c) concrete gutter, curb and sidewalks (if being done at the time).
Any deficiencies found by the City Engineer shall be corrected before
proceeding to the next phase of construction.
(6)
Tests of materials. The City shall be provided with a sample of the
roadway base material prior to placement on the roadway. The City
shall also be provided with copies of test reports performed by an
independent testing lab indicating test results for material gradation
and soundness.
B.
Construction standards. All streets and highways constructed in the
City or to be dedicated to the City shall fully comply with the following
construction standards and shall be adequate for the zoning classification
or projected use of the area served by the street:
(1)
General. After completion of the underground utilities and approval
thereof, the streets shall be constructed. Unless excepted, building
permits shall not be issued prior to the installation of the street
improvements and the approval of an individual lot grading plan that
conforms to the guidelines of the master site grading plan, as determined
by the City Engineer, or his designee.
(2)
Temporary streets. Construction of temporary streets shall require
authorization of the Planning Committee.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
(3)
Standard street improvements.
(a)
Streets shall be constructed according to the standards prescribed
in the specifications appendix, incorporated herein by reference,
entitled "Typical Residential Street Cross Section."[1]
[1]
Editor's Note: The illustration is included as an attachment to this chapter.
(b)
The construction of standard street improvements can begin only
when the construction of underground utilities has been completed
and mechanical compaction test reports have been approved by the City
Engineer.
(c)
Upon obtaining the written approval of the City Engineer, the
subdivider can proceed with the construction of the standard street
improvements. Standard street improvements shall be installed to the
boundary line of the subdivision unless the street culminates in a
cul-de-sac, the topography or other physical conditions make it impossible
to do so, or unless this requirement is waived, in writing, by the
Common Council.
(4)
Roadway base standards.
(a)
The subdivider must bring all streets and alleys to a grade
established by the Common Council. All site work by City employees
in determining grade shall be billed at the City rate and paid by
the owner.
(b)
Roadway subbase a minimum thickness of 13 inches of breaker-run
stone shall be provided. Residential streets shall have a minimum
eight inches thick, compacted in place, crushed stone roadway base.
A pavement drainage system consisting of six-inch perforated wrapped
underdrains shall be provided along both edges of the roadway excavation
which shall serve to drain the successive pavement structure layers
and adjacent native soils.
(c)
In the case of commercial, arterial or other heavy-use roads,
the Common Council may, in the alternative to these standards, have
the City Engineer provide specifications for such roads after researching
the site(s) and conducting a soil analysis for separate pavement design
analysis.
(d)
In any case, the Common Council shall have the sole discretion
in determining the use and construction classification to be adhered
to.
(e)
In all cases, the base course shall be compacted to the extent
necessary to produce a condition so that there will be no appreciable
displacement of material laterally and longitudinally under traffic
and shall conform to line, grades and shape shown on the approved
plans, profiles and cross-sections. Compaction shall be to 95% modified
Proctor ASTM D1557. Testing shall be conducted by nuclear density
meter or as otherwise approved by the City Engineer.
(f)
The subdivider shall furnish drawings which indicate the proposed
grades of streets shown on the plat and, after approval of those grades
by the City Engineer and adoption by the Common Council, the streets
shall be graded to full width of the right-of-way of the proposed
street to the subgrade elevations shown on the typical cross-section.
The grading is to be completed prior to installation of utilities.
All stumps and trees which cannot be saved, boulders and other similar
items shall be removed by the subdivider.
(5)
Roadway subgrade quality. All subgrade material shall have a minimum
California Bearing Ratio (CBR) of three. Subgrade material having
a CBR less than three shall be removed and replaced with a suitable
fill material, or the pavement must be designed to compensate for
the soil conditions. The soil support CBR values selected for use
by the designer should represent a minimum value for the soil to be
used.
(6)
Roadway subbase. Stable and nonorganic subbase material is required.
Unstable and organic material must be subcut, removed and replaced
with a suitable granular or breaker-run material approved by the City
Engineer.
(7)
Pavement thickness. The City shall install asphalt paving and pay
the cost thereof. The thickness of the pavement shall be as required
by the Typical Residential Street Cross Section[2] or as prescribed by the City Engineer in accordance with
the functional classification of the proposed street and soil subgrade
data available.
[2]
Editor's Note: The illustration is included as an attachment to this chapter.
(8)
Roadway culverts and bridges. Roadway culverts and bridges shall
be constructed as directed by the City Engineer and sized utilizing
the methods listed in Chapter 13, entitled "Drainage," of the Facilities
Development Manual of the Wisconsin Department of Transportation.
All roadway culverts shall be provided with concrete or metal apron
endwalls. All culverts shall be designed to pass a ten-year, twenty-four-hour
duration storm event.
(9)
Driveways.
(a)
Curbs shall not be interrupted by openings for driveways or
other accessways to private property unless the number and location
of such interruptions have been approved by the Planning Committee.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
(b)
The culverts shall be placed in the ditch line at elevations
that will assure proper drainage, and they shall be provided with
concrete or metal endwalls.
(10)
Topsoil, grass, seed, fertilizer and mulch. All disturbed areas
(ditches, backslopes) within the road right-of-way not provided with
pavement and shouldering material shall be restored utilizing four
inches of topsoil and good-quality grass seed, fertilizer and mulch.
Ditches along the roadway with greater than a 2% slope shall be protected
by erosion control materials such as hay bales, sod, erosion control
mats, etc.
(11)
Drainage improvements. All new roads and streets shall be provided
with stormwater retention areas, drain tiles and storm sewers in order
to provide for proper drainage.
(12)
Continuity and transitions.
(a)
All street pavement widths on streets continued from previously
developed or platted streets shall, wherever practical, provide for
the greater of either the existing or required pavement type, width,
grade and cross slope.
(b)
Where it is necessary to provide for a transition of pavement
width and/or type between new and existing streets, the transition
shall occur in a safe manner at an intersection. In width transitions,
the ratio of the transition length to width shall not be less than
40:1 unless the City Engineer determines that special circumstances
prevent use of such ratio, in which case the minimum transition ratio
shall be 20:1.
(13)
Curb and gutter. Combination concrete curb and gutter is required on all streets. Refer to § 472-27, describing requirements for curbs and gutters. The cost of curb and gutter shall be specially assessed to adjacent property owners.
(14)
Post-construction traffic limited. No vehicular traffic shall
be permitted on the pavement for a minimum period of between 24 hours
and 72 hours following paving, as determined necessary by the City
Engineer to protect the new pavement.
A.
Length; arrangement. The lengths, widths and shapes of blocks shall
be appropriate for the topography and the type of development contemplated,
but block length (measured in the long dimension from street center
line to street center line) shall not be less than 500 feet nor exceed
1,200 feet nor have less than sufficient width to provide for two
tiers of lots of appropriate depth between street lines. Blocks shall
be so designed as to provide two tiers of lots, unless the block adjoins
a railroad, major thoroughfare, river or park, where it may have a
single tier of lots. Culs-de-sac may be used where the interblock
spacing of adjacent streets exceeds the appropriate depth of two tiers
of lots.
B.
Pedestrian pathways. Pedestrian pathway easements not less than 10
feet wide, with a five-foot sidewalk, may be required by the Common
Council through the center of a block more than 900 feet long, where
deemed essential to provide circulation or access to schools, playgrounds,
shopping centers, transportation and other community facilities.
C.
Street tree planting strip easements. Tree planting strip easements
shall be provided for on both sides of all streets when the street
terrace is insufficient. The minimum easement width shall be 10 feet
and shall be adjacent to the front property line. Street trees shall
be maintained by the adjacent property owner in accordance with City
ordinances.
A.
Size.
(1)
The size, shape and orientation of lots shall be appropriate for the location of topography of the land division and for the type of development contemplated, provided that no lot shall be smaller in area than the minimum lot size for the appropriate zone as established by Chapter 480, Zoning, of the City Code.
(2)
Lot dimensions, shape and size shall provide for conformance to the requirements of Chapter 480, Zoning, of the City Code for the permitted land use(s) without the need for the granting of Zoning Code variances by the Zoning Board of Appeals. Excessive depth in relation to width shall be avoided.
B.
Commercial or industrial lots. Depth and width of properties reserved or laid out for commercial or industrial purposes shall be adequate to provide for the off-street service and parking facilities required by the type of use and development contemplated, as required by Chapter 480, Zoning, of the City Code.
C.
Minimum lot frontage. All lots on curved streets and culs-de-sac shall have a minimum of 50 feet of platted frontage on a public street to allow access by emergency and service motor vehicles unless part of a planned unit development approved by the Common Council. In any case, minimum lot width at building setback line shall be in conformance with the requirements of Chapter 480, Zoning, of the City Code. Alley frontage (public or private) shall not constitute meeting this minimum frontage requirement.
D.
Corner lots. Corner lots for residential use shall have extra width
to permit full building setback from both streets, or as required
by applicable zoning regulations.
E.
Access to public streets. Every lot shall front or abut on a public
street.
F.
Side lots. Side lot lines shall be substantially at right angles
to straight street lines or radial to curved street lines. Lot lines
shall follow City boundary lines.
G.
Double- and reversed-frontage lots. Double-frontage and reversed-frontage
lots shall be avoided except where necessary to provide separation
of residential development from traffic arteries or to overcome specific
disadvantages of topography and orientation.
H.
Natural features. In the dividing of any land, regard shall be shown
for all natural features, such as tree growth, watercourses, historic
spots or similar conditions which, if preserved, will add attractiveness
and stability to the proposed development.
I.
Land remnants. All remnants of lots below minimum size left over
after dividing of a larger tract must be added to adjacent lots, or
a plan shown as to future use, rather than allowed to remain as unusable
parcels.
J.
Large lots. In case a tract is divided and results in parcels of more than twice the minimum lot size provided for by Chapter 480, Zoning, of the City Code for the zoning district in which the land is located, such parcels shall be so arranged as to permit redividing into parcels in accordance with this chapter and with Chapter 480, Zoning, of the City Code.
K.
Trunk highway proximity. All lots adjacent to state trunk and federal
highways shall be platted with additional depth necessary to provide
for a building setback line not less than 50 feet from the nearer
right-of-way line or 110 feet from the center line, whichever is more
restrictive (Ch. Trans 233, Wis. Adm. Code). The subdivider may appeal
this requirement to the City Engineer. Upon written request of the
City Engineer, the Wisconsin Department of Transportation is hereby
authorized to then determine building setback requirements equal to
or less than those required above in all land divisions (including
certified surveys) adjacent to state and federal highways in accordance
with the authority granted in the Wisconsin Administrative Code. The
required building setback line and additional lot depth shall be platted
so as to accommodate such required building setbacks.
L.
Easement allowance. Lots containing pedestrian or drainage easements
shall be platted to include additional width in allowance for the
easement.
M.
Drainageways and watercourses. Lots abutting upon a watercourse,
drainageway, channel or stream shall have such additional depth or
width as required by the City Engineer to obtain building sites that
are not subject to flooding from a post-development, 100-year, 24-hour
duration storm event.
A.
Purpose. The following provisions in this section are established
to preserve and provide properly located public sites and facilities
for drainage and stormwater management as the community develops,
and to ensure that the costs of providing and developing such public
sites are equitably apportioned on the basis of serving the need for
the management of increased stormwater quantities resulting from land
development.
B.
Drainage system required.
(1)
As required by § 472-31, a drainage system shall be designed and constructed by the subdivider to provide for the proper drainage of the surface water of the land division and the drainage area of which it is a part. A final plat shall not be approved until the subdivider shall submit plans, profiles and specifications as specified in this section, which have been prepared by a registered professional engineer and approved or modified by the Common Council, upon the recommendations of the Planning Committee and City Engineer. Drainage systems shall be designed to accommodate a ten-year storm event.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
(2)
Lots shall be laid out so as to provide positive drainage away from
all buildings, and individual lot drainage shall be coordinated with
the general storm drainage pattern for the area. Drainage shall be
designed so as to avoid concentration of storm drainage water from
each lot to adjacent lots.
(3)
The Planning Committee shall not recommend for approval any subdivision
plat which does not provide adequate means for stormwater or floodwater
runoff. Any stormwater drainage system will be separate and independent
of any sanitary sewer system. Storm sewers, where necessary, shall
be designed in accordance with all governmental regulations, and a
copy of design computations for engineering capacities shall accompany
plans submitted by the planning engineer for the final plat. When
calculations indicate that curb capacities are exceeded at a point,
or that stormwater will extend more than 10 feet beyond the face of
the curb, no further allowance shall be made for flow beyond that
point, and basins shall be used to intercept flow at that point.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
C.
Drainage system plans.
(1)
The subdivider shall submit to the City at the time of filing a preliminary
plat a preliminary drainage plan or engineering report on the ability
of existing watercourse channels, storm sewers, culverts and other
improvements pertaining to drainage or flood control within the subdivision
to handle the additional runoff which would be generated by the development
of the land within the subdivision. Additional information shall be
submitted to adequately indicate that provision has been made for
disposal of surface water without any damage to the developed or undeveloped
land downstream or below the proposed subdivision. The report shall
also include:
(2)
A grading plan for the streets, blocks and lots shall be submitted
by the subdivider for the area within the subdivision.
(3)
The design criteria for storm drainage systems shall be based upon
information provided by the City Engineer.
(4)
Material and construction specifications for all drainage projects
(i.e., pipe, culverts, seed, sod, etc.) shall be in compliance with
specifications provided by the City Engineer.
D.
Drainage system requirements. The subdivider shall install all the storm drainage facilities indicated on the plans required in Subsection A of this section necessary to serve, and resulting from, the phase of the land division under development.
(1)
Street drainage. All streets shall be provided with an adequate storm
drainage system. The street storm system shall serve as the minor
drainage system and shall be designed to carry street, adjacent land
and building stormwater drainage. Stormwater shall not be permitted
to be run into the sanitary sewer system within the proposed subdivision
or to run across street intersections.
(2)
Off-street drainage. The design of the off-street major drainage system shall include the entire watershed affecting the land division and shall be extended to a watercourse or ditch adequate to receive the storm drainage. When the drainage system is outside of the street right-of-way, the subdivider shall make provisions for dedicating an easement pursuant to Subsection F to provide for the future maintenance of said system.
E.
Protection of drainage systems. The subdivider shall adequately protect
all ditches to the satisfaction of the City Engineer. Ditches and
open channels shall be seeded, sodded or paved depending upon grades
and soil types. (Generally, ditches or channels with grades up to
1% shall be seeded; those with grades up to 4% shall be sodded; and
those with grades over 4% shall be paved or lined with rip-rap.)
F.
Drainage easements. Where a land division is traversed by a watercourse,
drainageway, channel or stream:
(1)
There shall be provided a stormwater easement or drainage right-of-way
conforming substantially to the lines of such watercourse and such
further width or construction, or both, as will be adequate for the
purpose and as may be necessary to comply with this section; or
(2)
The watercourse or drainageway may be relocated in such a manner
that the maintenance of adequate drainage will be assured and the
same provided with a stormwater easement or drainage right-of-way
conforming to the lines of the relocated watercourse, and such further
width or construction, or both, as will be adequate for the purpose
and may be necessary to comply with this section; or
(3)
Wherever possible, drainage shall be maintained in an easement by
an open channel with landscaped banks and adequate width for maximum
potential volume flow. In all cases, such easements shall be of a
minimum width established at the high-water mark plus 10 feet.
G.
Dedication of drainageways. Whenever a parcel is to be subdivided
or consolidated and embraces any part of a drainageway identified
on a City Comprehensive Stormwater Management Plan, Master Plan and/or
Official Map, or any portion thereof, such part of said existing or
proposed public drainageway shall be platted and dedicated by the
subdivider as an easement or right-of-way in the location and at the
size indicated, along with all other streets and public ways in the
land division. Whenever any parcel is to be subdivided or consolidated
and is part of a drainage district established under the authority
of Ch. 88, Wis. Stats., the subdivider shall petition the Circuit
Court to transfer the jurisdiction of that portion of the drainage
district being subdivided or consolidated to the City in accordance
with § 88.83, Wis. Stats.
H.
Dedication/Preservation of stormwater management facilities.
(1)
The subdivider is responsible for the entire cost of the drainage
basin at the time of construction. The drainage basin requirements
for the area needed for this project and future other developments
would be determined at this time. If a future developer seeks to develop
included property, such developer would be responsible for a percentage
of the original cost of the drainage basin, payable to the original
developer.
(2)
The subdivider shall dedicate sufficient land area for the storage
of stormwater to meet the needs to be created by the proposed land
development and in accordance with the standards for on-site detention
and as determined by the City Engineer. Whenever a proposed stormwater
management facility (e.g., detention or retention basin) shown on
the Comprehensive Stormwater Management Plan (if applicable), Master
Plan and/or Official Map is located, in whole or in part, within the
proposed land division, ground areas for providing the required storage
capacity in such proposed public facility shall be dedicated to the
public to the requirements of the Master Plan and/or Official Map.
I.
Storm drainage facilities.
(1)
The subdivider, at his cost, shall install all drainage facilities
identified in the erosion control plan or determined by the City Engineer
as being necessary for the management of all lands and roadways within
the development. In addition, drainage capacity through the development
from other areas shall be provided in accordance with a comprehensive
surface water management study, if applicable. All required storm
drainage facilities shall be constructed and operational prior to
acceptance of any dedications and/or public improvements served by
the storm drainage facilities.
(2)
The subdivider shall submit to the City Engineer for his review and
approval a report on the ability of existing watercourse channels,
storm sewers, culverts and other improvements pertaining to drainage
or flood control within the land division to handle the additional
runoff which would be generated by the development of the land within
the land division. Additional information shall be submitted to adequately
indicate that provision has been made for disposal of surface water
without any damage to the developed or undeveloped land downstream
or below the proposed land division. The report shall also include:
(3)
A grading plan for the streets, blocks and lots shall be submitted
by the subdivider for the area within the land division.
(4)
The design criteria for storm drainage systems shall be reviewed
by the City Engineer and approved or modified.
(5)
Material and construction specifications for all drainage projects
(i.e., pipe, culverts, seed, code, etc.) shall be in compliance with
standards and specifications provided by City ordinance and/or the
City Engineer.
J.
Minor drainage system. The subdivider shall install all minor drainage
system components necessary to reduce inconvenience and damages from
frequent storms. Minor drainage components shall include all inlets,
piping, gutters, channels, ditching, pumping and other facilities
designed to accommodate the post-development runoff resulting from
a ten-year, twenty-four-hour rainfall event as determined in the most
current edition of the Natural Resources Conservation Service Technical
Release 55 (TR 55). Temporary accumulations of storm runoff from ponding
or flowing water, in or near minor system components, shall be permitted,
provided such accumulations do not encroach on any traffic lane of
any collector or arterial street, nor on the center 16 feet of any
local street, except on cul-de-sac or permanently dead-end streets
serving less than 10 dwelling units, where such accumulations may
not overtop the curb. In drainageways and drainageway easements, accumulations
of water shall not inundate beyond the limits of the drainageway or
drainageway easement. Cross-street drainage channels (valley gutters)
shall not be permitted.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
K.
Major drainage system. The subdivider shall install all major drainage
system components necessary to reduce inconvenience and damages from
infrequent storms. Major system components shall include large channels
and drainageways, streets, easements and other paths and shall be
capable of accommodating post-development runoff in excess of that
accommodated by minor system components resulting from twenty-four-hour
rainfall events for storms with return frequencies greater than 10
years, up to and including the 100-year return event (as identified
in TR 55). On local and collector streets and drainageways and drainage
easements, accumulations of water shall not inundate any buildings
at the ground line, unless such buildings are floodproofed. On arterial
streets and in commercial zoning districts, accumulations of water
shall not inundate any buildings at the ground line, unless such buildings
are floodproofed and the depth of water at the street crown shall
not exceed six inches to permit operation of emergency vehicles.
L.
Drainage piping systems.
(1)
Unless otherwise approved by the City Engineer, all drainage piping
of 12 inches diameter and greater shall be constructed of reinforced
concrete pipe class adequate for proposed street loading. Open drainage
inlet pipes or culverts with any opening dimension in excess of 18
inches shall be equipped with debris grates having an exposed area
at least seven times the pipe opening area to avoid backwater accumulations
from trash buildup and unsafe stream velocities and a maximum opening
size of six inches. Drainage piping outfalls with any opening dimension
in excess of 36 inches shall be protected from unauthorized entry
by fencing, partial or total submergence of the outlet, debris grates
or other methods approved by the City Engineer unless in such a location
as to render routine maintenance operations impossible. Outfalls and
their channels shall be protected from damages due to scour and erosion
to the satisfaction of the City Engineer.
(2)
Agricultural drain tiles which are disturbed during construction
shall be restored, reconnected or connected to public storm drainage
facilities.
M.
Open channel systems.
(1)
Where open channels are utilized in either the minor or major drainage
system, they shall be designed so as to minimize maintenance requirements
and maximize safety. Drainage easements (in lieu of dedications) shall
be utilized to accommodate open channels provided adequate access
by the City for maintenance of drainage capacity. Side slopes shall
not exceed a four-to-one slope. Drainageways with grades of 0.75%
or less, or where subject to high groundwater, continuous flows or
other conditions as determined by the City Engineer that would hamper
maintenance operations due to consistently wet conditions, shall have
a paved concrete invert of not less than eight feet wide and side
slopes to a point one foot above the channel invert.
(2)
In areas where invert paving is not required, the drainageway bottom
shall be grass. If the drainageway has a bare soil bottom or the natural
grasses in the drainageway are disturbed due to development operations,
the drainageway bottom shall be sodded and securely staked to one
foot above the elevation of inundation resulting from a pre-development
ten-year, twenty-four-hour storm event. Other disturbed areas shall
be seeded and prepared in accordance with the City's erosion control
requirements. Velocities for grass-lined channels shall not exceed
those presented in the City's Surface Water Management Study, if one
is adopted.
N.
Standards for on-site detention storage. The subdivider shall employ
on-site detention to control erosion and sedimentation, reduce the
post-development peak runoff rate or temporarily store stormwater
runoff due to inadequate downstream drainage facilities. The detention
(storage) facilities shall be subject to regulation in accordance
with the following standards:
(1)
Where on-site detention is temporarily employed for erosion and sedimentation
control, the detention facilities shall safely contain the pre-development
runoff from a twenty-five-year storm event of twenty-four-hour duration
within the limits of the facility.
(2)
Where on-site detention is permanently employed to reduce the post-development
peak runoff, the detention facility shall safety contain the post-development
runoff from a twenty-five-year storm event of twenty-four-hour duration
within the limits of the facility.
(3)
Detention facility peak discharge rates for the maximum storm required
to be contained shall not exceed the pre-development peak discharge
rate from a ten-year storm event of twenty-four-hour duration or the
capacity of the downstream drainage facilities, whichever is less.
(4)
All temporary detention facilities shall safety contain or pass the
runoff from any storm of any duration which exceeds the maximum storm
required to be contained up to the 100-year storm event of twenty-four-hour
duration.
(5)
All permanent detention facilities shall safely contain or pass the
runoff from any storm of any duration which exceeds the maximum storm
required to be contained up to the 100-year storm event of twenty-four-hour
duration on both public and, if necessary, private properties without
inundating any building at the ground elevation, the travel lanes
of any arterial street, the center 10 feet of any collector street
or the top of the curb on any local street.
(6)
Determination of on-site detention volumes shall be computed by procedures
established by the United States Natural Resources Conservation Service
in the most current edition of its technical publication entitled
"Urban Hydrology for Small Watersheds, TR-55," and as accepted and
approved by the City Engineer.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
(7)
The storage of stormwater runoff shall not encroach on any public
park (except parks designed with detention facilities) or any private
lands outside the land division unless an easement providing for such
storage has been approved and recorded for said lands.
(8)
All detention facilities shall be designed with the safety of the
general public and any considerations for ease of maintenance as top
proprieties.
(9)
Any wet detention facilities shall include riprap to not less than
two feet above the normal pool elevation for protection from wave
action.
(10)
The sides of all detention facilities shall have a maximum slope
ratio of four to one (horizontal to vertical), with flatter slopes
being required where determined practical by the City Engineer.
(11)
The Common Council, upon recommendation by the City Engineer,
may require the installation of fencing or other such security measures
in detention facilities with excessively long down times or permanent
water features, or other features requiring additional security for
safety reasons.
A.
General.
(1)
If a proposed subdivision includes land that is zoned for commercial
or industrial purposes, the layout of the subdivision with respect
to such land shall make such provisions as the City may require.
(2)
A nonresidential subdivision shall also be subject to all the requirements of site plan approval set forth in the City Building Code. A nonresidential subdivision shall be subject to all the requirements of this chapter, as well as such additional standards required by the City, and shall conform to the proposed land use standards established by any City Comprehensive Plan or Official Map and Chapter 480, Zoning, of the City Code.
B.
Standards. In addition to the principles and standards in this chapter,
which are appropriate to the planning of all subdivisions, the applicant
shall demonstrate to the satisfaction of the Common Council that the
street, parcel and block pattern proposed is specifically adapted
to the uses anticipated and takes into account other uses in the vicinity.
The following principles and standards shall be observed:
(1)
Proposed industrial parcels shall be suitable in area and dimensions
to the types of industrial development anticipated.
(2)
Street rights-of-way and pavement shall be adequate to accommodate
the type and volume of traffic anticipated to be generated thereupon.
(3)
Special requirements may be imposed by the Common Council, upon the
recommendation of the City Engineer, with respect to street, curb,
gutter and sidewalk design and construction.
(4)
Special requirements may be imposed by the Common Council, upon the
recommendation of the City Engineer, with respect to the installation
of public utilities, including water, sewer and stormwater drainage.
(5)
Every effort shall be made to protect adjacent residential areas
from potential nuisance from a proposed commercial or industrial subdivision,
including the provision of extra depth in parcels backing up on existing
or potential residential development and provisions for permanently
landscaped buffer strips when necessary.
(6)
Streets carrying nonresidential traffic, especially truck traffic,
shall not normally be extended to the boundaries of adjacent existing
or potential residential areas.
The subdivider shall grade each land division in order to establish
street, block and lot grades in proper relation to each other and
to topography as follows:
A.
Master site-grading plan.
(1)
A master site-grading plan shall be prepared by the subdivider for
all new subdivisions. This plan shall be prepared in accordance with
the requirements and standards of the City.
(2)
The master site-grading plan shall show existing and proposed elevations
of all lot corners, control points and building locations. The plan
shall also indicate all overland storm drainage in and adjacent to
the subdivision. The cost of the preparation of such a plan shall
be paid for by the subdivider.
(3)
After approval or modification of these plans by the City Engineer,
the full width of the right-of-way of the proposed streets within
the subdivision and the entire subdivision lot area shall be graded
in accordance with the master site-grading plan. The owners of the
subdivision lots shall adhere to those plans.
(4)
Upon completion of all street and subdivision grading, the grades
shall be checked and inspected by the Building Inspector to determine
that the completed grading work is in accordance with the master site-grading
plan. All grades shall be within 0.4 of a foot of the elevations shown
on the master site-grading plan.
(5)
The cost of all required grading work, supervision, certification,
inspection and engineering fees shall be paid for by the subdivider.
B.
Right-of-way grading. The subdivider shall grade the full width of
the right-of-way of all proposed streets in accordance with the approved
plans, including the grading of sight triangles at each intersection.
C.
Block grading. Block grading shall be completed by one or more of
the following methods prior to the installation of utilities:
(1)
Regrading along the side or rear lot lines which provides for drainage
to the public drainage facilities.
(2)
Parts of all lots may be graded to provide for drainage to a ditch
or to a swale, provided any ditches or swales are in public drainage
easements.
(3)
Draining across rear or side lot lines may be permitted, provided
that the course of drainage is within a public drainage easement and
is toward public drainage facilities.
D.
Miscellaneous grading requirements.
(1)
Lot grading shall be completed so that water drains away from each
building site toward public drainage facilities at a minimum grade
of 1%, and provisions shall be made to prevent drainage onto properties
adjacent to the land division unless to a public drainage facility.
(2)
Grading activities shall not result in slopes greater than three
to one on public lands or lands subject to public access.
(3)
The topsoil stripped for grading shall not be removed from the site
unless identified in the erosion control plan approved by the City
Engineer as not being necessary for erosion control or site landscaping
purposes. Topsoil shall be uniformly returned to the lots when rough
grading is finished. Topsoil piles shall be leveled and seeded for
erosion control prior to the City releasing the one-year guarantee
provision on public improvements in the streets adjacent to the lots
on which the topsoil is stockpiled.
(4)
Such grading shall not result in detriment to any existing developed
lands, either within or outside of the corporate limits.
