[R.O. 2008 § 405.130; Ord. No. 6496, 9-13-2018]
In the City Council's consideration
of applications for plat approval, the standards set forth in this
Article shall be considered minimum requirements.
[R.O. 2008 § 405.180; Ord. No. 6496, 9-13-2018; Ord. No. 7056, 10-26-2023]
A.
Utility Easement Requirements.
1.
Utility Easements. Utility easements shall be provided and be
at least ten (10) feet wide [five (5) feet on each side of the lot
line] along rear, front and side lot lines. Easements of adequate
width shall be provided for open drainage channels and rear yard swales,
where required. Easements five (5) feet in width may be allowed for
underground cable installations. Telephone and electric power lines
shall be located underground, except in large lot subdivisions where
all of the lots are twenty-two thousand (22,000) square feet or larger
in size, and then the developer will have the option of underground
or overhead utility lines.
2.
Utility/Roadway Easements. A minimum of a ten-foot utility/roadway
easement shall be required adjacent to all City, County and State
rights-of-way. Such utility/roadway easements shall also include working
space to work on such utility and/or roadway.
3.
All underground public utility installations, including lines
for streetlighting systems, which traverse privately owned property,
shall be protected by easements granted by the developer to the appropriate
public utility and reasonably approved by the public utility. Such
easements shall be so located as to not interfere with the use of
any lot or other part of the subdivision. The size of, and restrictions
pertaining to, such easements shall be in accordance with the legally
adopted or reasonable standards and the specifications of the agency
having jurisdiction over the utility lines and subdivision and shall
be indicated on the record plat submitted for approval.
4.
Where a cut or fill for a street extends beyond the limits of
the right-of-way, the developer shall provide a slope easement as
determined by the City Engineer and/or his/her designee to be of sufficient
area and limits to permit the construction and maintenance of the
slope.
5.
Stormwater easements and drainage rights-of-way may be required
by the City of O'Fallon if necessary for proper drainage within
or through a subdivision. Whenever a stream or surface drainage course
conveying a minimum of one and one-half (1.5) cfs in a fifteen-year,
twenty-minute storm is located in or planned for an area proposed
for a subdivision, the developer shall provide a minimum ten-foot-wide
easement or wider as determined by the City Engineer and/or his/her
designee to be adequate in area to contain facilities, to control
flooding or erosion along said stream or surface drainage course and
protect the facility from blockages. Said easements shall be shown
on the record plat with the following language: This easement is for
emergency or access purposes; however, regular yard maintenance would
fall on the property owner.
B.
Off-Site Utility Easement.
1.
For any existing off-site utility easements that are dedicated
to the City of O'Fallon but are desired to be utilized by a new
development, the following are required:
a.
Only public-type facilities (mains that will be maintained by
the public utility) can be placed within these easements. No private
service lines or laterals can utilize these easements, unless otherwise
approved by the City Engineer or their designee.
b.
The owners of the property where the existing off-site easements
reside should be notified in writing and at a minimum of forty-eight
(48) hours in advance of the anticipated work, of any impacts to that
property (either physical alterations of the property or losses of
some service of the property). Any concerns shall be addressed with
the property owner. Failure to reasonably restore the property to
its prior condition may result in withholding of escrow releases or
issuances of related permits until these issues are addressed. The
Engineering Department shall be provided copies of any and all agreements,
notifications and correspondences with the property owner prior to
construction plan approval.
c.
If the adjacent property owner is a common ground or private
property (with no apparent off-site easements providing rights), then
the developer of the project shall be required to obtain new off-site
easements prior to plan and/or permit approval.
d.
The City is not responsible for the acquisition of these off-site
easements.
[Ord. No. 7056, 10-26-2023]
A.
Side Yard Easement Requirements.
1.
Side Yard Easements For Utilities. Wider side yard easements,
beyond the minimum typical lot side yard easements, shall be provided
when certain utilities are to be installed along side yards. Utilities
shall be limited to any public sanitary sewer main, water main, or
storm sewer. Easements totaling fifteen (15) feet in total width shall
be placed between houses, in lieu of the default side yard easements.
a.
Extended Foundation. An extended foundation will be required
when any of the said utilities are installed along the side yard.
Foundations will be extended such that the foundation is outside of
the 1:1 shear plan along the utility.
2.
Side Yard Easements for Emergency Relief Swales. Wider side
yard easements, beyond the minimum typical lot side yard easements,
shall be provided when emergency relief swales are to be installed
along side yards. Easements shall commence at the right-of-way line
and continue until another swale takes over or a storm structure intercepts
the swale. Easements totaling fifteen (15) feet in total width shall
be placed between houses, in lieu of the default side yard easements.
[R.O. 2008 § 405.200; Ord. No. 6496, 9-13-2018]
A.
Street name signs meeting the requirements
of the City of O'Fallon shall be erected by the subdivider at all
intersections.
B.
Stop signs, yield signs, etc., non-illuminated,
non-electric, reflectorized shall conform to the current Manual on
Uniform Traffic Control Devices and be provided by the developer as
determined by the City of O'Fallon.
C.
Whenever a new street is constructed along
the approximate alignment or extension of an existing street, its
name shall be the same as that of the existing one.
D.
Whenever a cul-de-sac street serves not
more than three (3) lots, the name of the intersecting street shall
apply to the cul-de-sac.
E.
To avoid duplication and confusion, the
proposed names of all streets shall be approved by St. Charles County
prior to preliminary plat approval and such names being assigned or
used.
[R.O. 2008 § 405.210; Ord. No. 6496, 9-13-2018; Ord. No. 6855, 12-16-2021; Ord. No. 7056, 10-26-2023]
A.
Public Street Construction. Streets shall be graded to full width
of the right-of-way and fully constructed of asphaltic concrete or
Portland cement concrete pavements in accordance with the St. Louis
County Department of Transportation Standard Drawings, latest revision,
and the St. Louis County Standard Specifications for Highway Construction,
Divisions 200 through 1000, latest revision, except as modified by
the City of O'Fallon's codes or ordinances.
1.
Those publications listed above shall be adopted in whole with
the following exceptions:
a.
Standard drawing numbers: C203.66-C203.70, C604, C614, and C725-C732
drawings are not adopted.
b.
All references to "St. Louis County" in any form shall be replaced
with "City of O'Fallon" where appropriate.
c.
All references to "department" shall mean the "Department of
Engineering of the City of O'Fallon" where appropriate.
d.
The standard details for construction of pavements shall follow
those standards established by the ordinances of the City. The ordinances
of the City of O'Fallon supersede and take precedence over the
St. Louis County Standard Specifications for Highway Construction
and standard details.
e.
Construction Staking. All construction staking shall be provided
by the contractor unless otherwise indicated by the City Engineer.
2.
The following additional modifications shall be included and
prevail over the adopted publications:
a.
All concrete used for public infrastructure (streets, sidewalks,
trails and curbs) in the City of O'Fallon shall be approved by
the Eastern Missouri Pavement Consortium (EMPC) and meet requirements
specified in City Ordinance No. 6335[1] approved on April 13, 2017. This includes roadways that
are being developed and intended to become public roadways upon dedication
and acceptance by the City.
[1]
Editor's Note: Ord. No. 6335 was repealed and replaced
September 13, 2018, by Ord. No. 6496.
b.
Per City Ordinance No. 6335[2] approved on April 13, 2017, underdrains shall be required
and installed per Exhibit A in Appendix D[3] of the O'Fallon City Municipal Code [Section 405.390(A)(5)]. Underdrains are required to be installed at all inlets. If a roadway has an open-type drainage system, underdrains are to be installed every five hundred (500) feet.
c.
A representative sample of proposed limestone, calcitic dolomite
or other mineral referred to as "limestone" that is used for coarse
aggregate for concrete shall undergo appropriate testing, by an independent
third-party testing agency to determine and verify that the coarse
aggregate to be utilized does not exhibit, and is not susceptible
to, alkali-carbonate reaction (ACR). Said third-party testing agency
or agencies will need to be a City-approved agency that is experienced
in performing the necessary tests.
d.
For ACR testing, the testing performed shall include ASTM C295,
ASTM C586 and ASTM C1105. The agency performing these tests must be
informed prior to testing to look specifically for the potential of
ACR, and the reports generated from the testing shall specifically
address the potential of ACR in the text. This testing shall be performed
for each ledge within a quarry that is planned to be used for concrete
pavement within the City of O'Fallon.
e.
The following requirements pertain to the ASTM C295 test. For
the first two (2) years of this requirement, the tests shall be made
within six (6) months of the planned use in concrete. After the first
two (2) years of testing within a quarry, the City Engineer may allow
the interval between tests to go up to one (1) year if there is convincing
evidence to show this is warranted. The petrograph test shall be performed
by a petrographer experienced in identifying ACR-prone dolomitic limestone
or calcitic dolomite. The reports of the testing noted herein shall
be submitted to the City with the concrete mix design submittal.
f.
The following requirements pertain to the ASTM C586 and ASTM
C1105 tests. These test reports shall be required to be submitted
to the City beginning on August 1, 2017. The period of time from approval
of this Chapter to when the reporting is required to be submitted
allows time for the tests to be completed. For the first two (2) years
of this requirement being in place, these tests shall be made within
twelve (12) months of the planned use in concrete pavement. After
the first three (3) years of testing within a quarry, the City Engineer
may allow the interval between tests to go up to two (2) years if
there is convincing evidence to show this is warranted.
g.
In lieu of performing the above testing, Meramec gravel can
be utilized for coarse aggregate in Portland cement concrete pavement.
The coarse aggregate shall be Meramec gravel meeting Missouri Department
of Transportation current "Missouri Standard Specifications for Highway
Construction," Section 100.5.1.5, Gradation "D."
h.
All coarse and fine aggregate material utilized for Portland
cement concrete pavement shall have been inspected and approved by
the Missouri Department of Transportation (MoDOT) for said use. If
MoDOT inspection is not available, a third-party testing agency that
is experienced in performing the necessary test will need to be approved
by the City. The delivery ticket shall be marked to indicate that
the rock has been tested and meets MoDOT specifications.
i.
Coarse aggregate utilized for Portland cement concrete pavement
shall only be used from rock ledges that have been inspected and accepted
by MoDOT for said use. If MoDOT inspection is not available, a third-party
testing agency that is experienced in performing the necessary test
will need to be approved by the City.
j.
A complete copy of the results of the above-referenced testing,
as well as mix design submittal information, MoDOT certifications
and other associated certifications required per this Chapter and
per the St. Louis County Standard Specifications for Road and Bridge
Construction shall be submitted to the City a minimum of seven (7)
days prior to the placement of the concrete. The City must be in agreement
with said test results, mix designs and certifications prior to the
placement of any concrete.
k.
For all granular base material deliveries, the delivery ticket
must be annotated or signed by the rock supplier to indicate that
the granular base material meets the Missouri Department of Transportation
(MoDOT) requirements for Type 5 aggregate for base. This ticket must
be submitted to the City for recordkeeping purposes at the time of
delivery. Any deliveries made without the proper delivery tickets,
including signature, will not be accepted for use. In lieu of a signature
on the delivery ticket a separate product certification sheet with
a signature of the company's quality control manager may be provided
to go with the delivery tickets. The product certification sheet must
be current, dated to within four (4) weeks of the date of delivery
and also list the project name or job site location.
3.
The minimum concrete pavement thickness shall be seven (7) inches
thick. On minor residential streets, the transverse joints are not
required to have load transfer devices. All other higher classifications
of streets will be required to have load transfer devices in the transverse
joints.
4.
The following is a list of deficiencies that shall require concrete
removal and replacement:
a.
More than one (1) crack in a slab shall require a full slab
replacement. However, if there is one (1) crack in the slab and there
is deflection in the crack or other structural concern, then the full
slab shall be replaced.
B.
Approval Of Subgrade And Base (Subbase). The City Engineer and/or
his/her designee shall approve the subgrade before any base is placed
thereon and shall approve the base before concrete or surface course
is placed. The subgrade and base shall be so constructed that it will
be uniform in density throughout.
1.
All subbase shall conform to a modified MoDOT Type 5 base [five
(5) inches thick] and/or as approved by the EMPC. The modified MoDOT
Type 5 rock shall meet all the requirements of MoDOT Type 5 rock and
also be required to have no more than ten percent (10%) fines passing
a No. 200 sieve. All gradations for this type of rock shall be submitted
to the City and/or the EMPC for approval prior to use.
2.
In all fill areas in the roadways, soil tests shall be submitted
and approved by the City Engineer for each foot of fill and at least
one (1) test and an average of one (1) test within every two hundred
fifty (250) feet.
3.
No traffic will be allowed on new concrete pavement until it
has cured for seven (7) days and it reaches three thousand five hundred
(3,500) psi. Concrete pavement shall not be approved unless it reaches
required strength within twenty-eight (28) days.
4.
Prior to placement of aggregate base material on subgrade and
prior to placement of pavement on base material, the subgrade and
base must be proof-rolled with a fully loaded (ten-ton load) tandem
truck or equivalent tire vehicle with one (1) pass down each driving
lane no faster than three (3) miles per hour. If soft spots are detected,
or pumping, rutting or heaving occurs greater than one (1) inch at
the subgrade, the roadbed shall be considered unsatisfactory, and
the soil in these areas shall be remediated to the depth indicated
by the contractor's testing firm and approved by a representative
of the City Engineer.
5.
Subgrade and base beneath pavements shall be compacted to St.
Louis County Standard Specifications for Road and Bridge Construction.
The moisture range shall be determined by the Standard or Modified
Proctor Density Method AASHTO T-99 and within -2)/+4 percentage points
of the optimum moisture content.
6.
The entire width and length will conform to line, grade and
cross section shown on the plans or as established by the engineer.
If any settling or washing occurs, or where hauling results in ruts
or other objectionable irregularities, the contractor shall improve
the subgrade or base to the satisfaction of the City before the pavement
is placed. Additional rolling or methods to verify compaction shall
be at the discretion of the City Engineer. Tolerance allowed on all
lines, grades and cross sections shall be plus or minus four-one-hundredths
(+ 0.04) feet.
C.
Utility Work Prior To Base Construction. No base course work may
proceed on any street until all utility excavations (storm and sanitary
sewers, water, gas, electric, etc.) have been properly backfilled
with granular material, crushed stone or gravel mechanically tamped
in ten-inch lifts. Utilities installed after subgrade preparation
shall be bored. Compaction requirements shall follow St. Louis County
standards.
D.
Outside (beyond) the pavement limits, excavations shall be jetted
with water and allowed to set for a length of time satisfactory to
the City Engineer.
1.
Jetting. Granular materials and earth materials associated with
new construction beyond the pavement may be jetted, taking care to
avoid damage to newly laid sewers. The jetting shall be performed
with a probe route on not greater than seven-and-one-half-foot centers
with the jetting probe centered over and parallel with the direction
of the pipe. Trench widths greater than ten (10) feet will require
multiple probes every seven-and-one-half-foot centers.
a.
Depth. Trench backfill less than eight (8) feet in depth shall
be probed to a depth extending to half the depth of the trench backfill,
but not less than three (3) feet. Trench backfill greater than eight
(8) feet in depth shall be probed to half the depth of the trench
backfill but not greater than eight (8) feet.
b.
Equipment. The jetting probe shall be a metal pipe with an exterior
diameter of one and one-half (1.5) to two (2) inches.
c.
Method. Jetting shall be performed from the low surface topographic
point and proceed toward the high point, and from the bottom of the
trench backfill towards the surface. The flooding of each jetting
probe shall be started slowly allowing slow saturation of the soil.
Water is not allowed to flow away from the ditch without first saturating
the trench.
d.
Surface Bridging. The contractor shall identify the locations
of the surface bridging (the tendency for the upper backfill crust
to arch over the trench rather than collapse and consolidate during
the jetting process). The contractor shall break down the bridged
areas using an appropriate method such as wheels or bucket of a backhoe.
When the surface crust is collapsed, the void shall be backfilled
with the same material used as trench backfill and rejetted. Compaction
of the materials within the sunken/jetted area shall be compacted
such that no further surface subsidence occurs.
E.
Required Joint Details In Concrete Streets. Construction joints shall
be required in all concrete roadways as a normal requirement. St.
Louis County Department of Transportation standards shall apply. Additionally:
1.
The developer's engineer shall identify on the record plat
any lot for which special precautions should be taken to prevent damage
to any structure caused by the forces commonly known as "street creep."
The developer's engineer shall also recommend any special construction
technique required to counter the forces.
F.
Material Testing And Frequency. Materials for construction shall
be tested and inspected per the appropriate ASTM code or at the City
Engineer's discretion. The developer's engineer shall perform
the following quality control guidelines:
1.
Concrete.
a.
Cylinders/Compressive Strength. One (1) set of four (4) cylinders
within the first fifty (50) cubic yards and one (1) set per one hundred
(100) cubic yards thereafter. One (1) cylinder must be tested at seven
(7) days, one (1) at fourteen (14) days and two (2) at twenty-eight
(28) days. If the first cylinder does not meet specifications at twenty-eight
(28) days, then the second cylinder must be held and tested at day
fifty-six (56).
b.
Percent Air And Temperature. First truck batch each day and
two (2) thereafter until a consistency is encountered. Once a consistency
is encountered, then tests will be performed in conjunction with the
concrete cylinders.
c.
Slump. First truck batch each day and two (2) thereafter until
a consistency is encountered. Once a consistency is encountered, then
tests will be performed in conjunction with the concrete cylinders.
d.
If concrete is batched from more than one (1) plant, then the
aforementioned guidelines will be applicable to each plant.
2.
Subgrade And Base.
a.
Proof roll as described in Section 405.210(B).
b.
One (1) compaction test per two hundred fifty (250) feet of
mainline paving, three (3) tests per intersection, five (5) tests
within culs-de-sac and one (1) test per repair slab.
c.
Gradation test for subbase material.
4.
Site Grading.
a.
Within City Right-Of-Way. Material is to be placed in eight-inch
to twelve-inch loose lifts and compacted per the approved compaction
requirements. One (1) compaction test will be performed every two
hundred fifty (250) feet along the center line for each lift.
b.
Outside Of City Right-Of-Way. Material is to be placed in eight-inch
to twelve-inch loose lifts and compacted per the approved compaction
requirements. One (1) compaction test will be performed at two-foot
vertical intervals and approximately every one thousand (1,000) cubic
yards.
5.
Quality Control Reports.
a.
Daily. Descriptive daily reports are required for each day a
representative is present on-site from the quality control company
(soil testing firm). At a minimum, the daily report should include
representative on-site, date, materials observed, activities performed,
weather, recommendations or concerns made and to whom.
b.
Proctor Reports. Must have a valid Proctor value prior to testing
on-site. At a minimum, the Proctor curve provided must include sample
location and must have five (5) density points (values) and moisture
(values) listed on the document, optimum moisture content, maximum
dry density, zero air voids curve and assumed specific gravity, natural
moisture content, Proctor type and procedure, liquid limit, plastic
limit.
c.
Compaction Report. At a minimum, the compaction reports will
include elevation of test and rod depth, station/specific location,
Proctor type, optimum moisture content, maximum lab dry density, in
place moisture content, in place dry density, percent compaction,
does/does not comply with specification requirements, specification
requirements, material type, weather, date. If a drawing is needed
to show location of the tests, the drawing must be professionally
done or at least on sheet copy of the plans. No hand drawings will
be accepted.
d.
Concrete Report. At a minimum, the field concrete report will
include location of concrete placed, representative on-site, date,
weather, concrete supplier, ticket and truck number, time truck arrived
on-site, time concrete poured, air temperature, concrete temperature,
mix type, strength requirement, water added, slump (actual and required),
air content (actual and required), number of cylinders cast, overnight
temperature, overnight storage temperature, date received at lab.
At a minimum, the laboratory concrete field report will include age
(days) of test, test date, cylinder diameter, cylinder area, load
(pounds), compressive strength (psi), does/does not comply with specification
requirements.
6.
Equipment Calibration. The developer's contractors and
subcontractors must have their equipment calibrated by the following
minimum standards:
G.
Specifications For Construction Of Driveway Entrances. All driveway
entrances constructed within the public right-of-way in the City of
O'Fallon shall meet the following specifications and conform
to site plan requirements. A permit shall be obtained through the
Engineering Department, for any driveway widening and/or modifications
to the driveway apron, within the City street right-of-way. A permit
will not be needed if the construction is part of another City-permitted
development:
1.
All driveway entrances shall be built to grade;
2.
The maximum grade of the driveway, behind the sidewalk, shall
be fifteen percent (15%). No portion of the driveway may exceed fifteen
percent (15%) in slope.
3.
If a culvert is necessary in the opinion of the Engineering
Department, no culvert smaller than twelve (12) inches in diameter
shall be installed, and no culvert shorter than sixteen (16) feet
shall be installed; a larger culvert shall be installed wherever,
in the opinion of the Engineering Department, it is necessary.
4.
No driveway entrances shall be constructed or built or partially
constructed or built within two (2) feet from the side or rear property
lines. No driveway shall be closer than six (6) feet from the edge
of a curb inlet.
Exceptions:
5.
All driveway entrances shall be six (6) inches in depth for
residential driveways and a minimum of seven (7) inches in depth for
commercial driveways from the edge of the road pavement to the property
line.
a.
For commercial driveways, for new concrete entrances at existing
pavement and curbing, saw cut at one (1) foot and install tie bars,
five-eighths-inch diameter, eighteen (18) inches long, at twelve-inch
centers along all saw-cut edges. New tie bars shall be placed in drilled
holes with non-shrink grout or epoxy. The bars, where existing, shall
be cleaned and straightened for incorporation in the new concrete.
b.
For commercial driveways, the new driveway edge up against existing
street pavement shall match the street pavement thickness. All street
pavement removed and replaced shall be the same thickness. After the
gutter line or the edge of street pavement line, it shall then flare
back to the seven-inch minimum depth within a two-foot length.
6.
All driveway approaches constructed in conjunction with a sidewalk
shall give the appearance that the sidewalk is continuous. That portion
of the driveway approach that doubles as a sidewalk shall have a one-and-one-half
percent (1.5%) maximum cross slope the same as the abutting sidewalk,
meeting ADA requirements.
a.
If the existing sidewalk adjacent to the driveway is over one
and one-half percent (1.5%) in cross slope, then the first panel of
sidewalk immediately adjacent to the driveway shall be removed and
replaced as a transition section.
b.
An exception to this requirement is when a sidewalk does not
exist nor is not planned to be built.
7.
Expansion joints in the driveway approach area shall be two
(2) inches wide and full depth at the back of curb. In all cases if
the driveway approach depth exceeds the minimum six-inch thickness,
the joint material shall extend the full depth of pavement, no concrete
to concrete interface.
8.
The expansion joint between the driveway and garage floor shall
be a minimum of two (2) inches and full depth of slab.
H.
Guardrail. The following additional modifications shall be included
and prevail over the adopted publications:
1.
Guardrail shall be required to protect traffic from hazardous
features, or to restrict or prohibit traffic movements. Guardrail
will be required for roadway heights (including fill) of ten (10)
feet or more adjacent to the roadway, or heights of seven (7) feet
or more at pavement terminations. Terminal sections will be required
for both directions of traffic flow on two-way pavement. Where the
distance between terminal sections of two sections of guardrail will
be one hundred (100) feet or less, one (1) continuous length of guardrail
shall be installed.
a.
Guardrail shall be provided for protection of traffic adjacent
to creeks and lakes, at bridge ends, piers, large signs (with no breakaway
base) and headwalls, and as street barricades, as directed by the
Engineering Department. Refer to the St. Louis County Standard Drawings
C606.01 through C606.23.
2.
Roadway Berms. The grading and placement of berms within the
road right-of-way as an alternate to guardrail may be permitted with
special approval by the Engineering Department where such installations
are considered compatible with the roadway typical section. Berms
shall be constructed to a height of three (3) feet above the adjacent
edge of pavement or curbs with 3:1 side slopes.
3.
Escape Area. The grading of an escape area as an alternate to
guardrail or roadway berms will have a slope no steeper than 6:1 and
will be permitted by the Engineering Department in accordance with
the following:
|
Minimum Escape Area Distance
| |
|---|---|
|
Design Speed
(MPH)
|
From Edge of Pavement to Breakpoint
(feet)
|
|
25
|
20
|
|
30 to 35
|
25
|
|
40
|
30
|
[R.O. 2008 § 405.220; Ord. No. 6496, 9-13-2018]
A.
As part of public street construction,
sufficient permanent and distinguished monuments shall be accurately
placed throughout the subdivision so that street alignment may be
traced with accuracy. Such monuments shall be in the form of iron
pins not less than one-half (1/2) inch in diameter and three (3) feet
long driven into the earth, or spikes not less than six (6) inches
long driven into the pavement, or of something equal. Such monuments
shall be installed by the subdivider as soon as reasonably possible.
The location of such monuments shall be indicated on the final plat
and shall be placed in accordance with the following requirements:
[R.O. 2008 § 405.230; Ord. No. 6496, 9-13-2018; Ord. No. 7056, 10-26-2023]
A.
In addition to the installation of curbs or gutters along the streets
as required by this Chapter, storm sewers shall be required. Such
systems will be equipped with adequate basins, inlets and outlets
and shall be constructed in accordance with the applicable provisions
in the specifications. The stormwater drainage system shall be separate
and independent of the sanitary sewer system. The plans and specifications
for the disposing of stormwater shall be approved by the City Engineer
and/or his/her designee.
B.
General. All construction details and specifications pertaining to
stormwater drainage shall be in accordance with the Metropolitan St.
Louis Sewer District (MSD) Standard Construction Specifications for
Sewers and Drainage Facilities, latest version, and the City of O'Fallon's
requirements, unless otherwise noted herein. A registered engineer's
seal is required on all drainage plans submitted for approval.
C.
Design Criteria. Unless otherwise specified below or in other City
of O'Fallon requirements, all engineering design shall adhere
to the Metropolitan St. Louis Sewer District (MSD) Rules and Regulations
and Engineering Design Requirements for Sanitary Sewer and Stormwater
Drainage Facilities, latest revision.
2.
All references to "District" in any form shall be replaced with
"City of O'Fallon" where appropriate.
3.
All stormwater design is to be by the Rational Method, except
that in certain large developments, the use of other methods of analysis
such as the Unit Hydrograph will be considered for stormwater design.
However, prior approval must be obtained from the City Engineer and/or
his/her designee at the preliminary design stage, where use of the
Unit Hydrograph or other methods of analysis are requested.
4.
Runoff factors shall be per the MSD requirements.
D.
Drainage Structures. All structures shall be designed for HS20-44
loading.
1.
Bridges. Bridges shall be designed for the 100-year storm frequency
and provide two (2) feet of freeboard between the bottom of superstructure
and highwater elevations.
2.
Culverts.
a.
Crossroad culverts, not at low points, shall be designed on
a storm frequency of fifteen (15) years with entrance control and
two (2) feet of freeboard at the shoulder line.
b.
Culverts, at or near low points in floodplains, shall be designed
on a storm frequency of one hundred (100) years with entrance control
and two (2) feet of freeboard at the shoulder line.
c.
Culverts, at or near low points not in floodplains, shall be
designed on a storm frequency of fifty (50) years with entrance control
and two (2) feet of freeboard at the shoulder line.
3.
Roadways. Whenever a watercourse is proposed or exists within
proximity of and is approximately parallel to an existing or proposed
roadway, the low shoulder elevation of the roadway shall be established
from the highwater elevation with one (1) foot of freeboard in non-floodplain
areas and two (2) feet of freeboard in floodplain areas.
4.
Street Inlets. In certain cases, where steep grades or other
unusual conditions are encountered, a grated trough may be required
in lieu of multiple inlet structures upstream in order to eliminate
excessive bypass.
5.
Pipes.
a.
Pipes within the public right-of-way or easement shall be reinforced
concrete pipe (RCP) ASTM C-76, Class III, and a minimum of twelve
(12) inches diameter. Design calculations may be submitted allowing
a lower class of RCP.
b.
The use of high-density polyethylene (HDPE) shall not be allowed.
c.
The use of polypropylene (PP) shall not be allowed.
d.
The use of corrugated steel pipe should only be considered when
all options for reinforced concrete pipe are deemed not feasible.
Corrugated steel shall be M-36, minimum sixteen-gauge asphalt polymer,
or aluminized coating, a minimum of eighteen (18) CSP, will be allowed
with these conditions. This pipe material may be used for private
driveway culverts or private road culverts, as the maintenance shall
be with the property owner, even though the pipe is in the right-of-way.
e.
Additional general pipe requirements.
(1)
The City Engineer and/or his/her designee shall
review the proposed project for suitability.
(2)
Standard concrete drainage structures and flared
end sections will be used in the installation process.
(3)
Installation shall be in accordance with ASTM D-2321
and/or manufacturer's recommendation, whichever is more stringent.
f.
The required stormwater hydraulics shall be submitted with all
types of pipes.
g.
Pipe reduction will not be allowed.
h.
In situations where storm pipe cover is less than three (3)
feet, calculations will be required to determine the class or gauge
of pipe.
i.
All new concrete pipe shall be installed with O-ring rubber-type
gaskets per MSD Standard Construction Specifications. Connections
at all existing structures are to be made with rubber, watertight
A-lock joints or approved equals, as determined in the preconstruction
meeting or prior to construction. Broken and/or unsuitable connections
shall be removed and replaced.
j.
Pipes normally should be sized using the partial flow design;
however, under special circumstances, full flow design will be allowed,
provided hydraulic grade line information is shown indicating adequate
freeboard. This additional information will be supplied for the fifteen-year
and 100-year storms.
k.
Freeboard requirements will be two (2) feet from the inlet sill
or manhole top.
l.
Starting Hydraulic Grade Line.
(1)
If a pipe run drains into a detention basin, then
the starting hydraulic grade shall be calculated for both the fifteen-year
routed and the 100-year low-flow blocked highwater elevations of the
basin. Freeboard requirements only apply to the fifteen-year calculations,
however for the 100-year calculations, all of the water must remain
within the structure.
(2)
If a pipe run drains into a naturally occuring
creek, then the starting hydraulic grade shall be calculated from
the hydraulic model of the creek for the 100-year highwater elevations
of the creek. For studied creeks, use the effective Flood Insurance
Study published by FEMA for that specific creek. For unstudied creeks,
use the MSD method of determining the 100-year highwater elevations
of the creek.
m.
If existing storm sewers are located near a proposed development,
where proposed storm sewers are planned, then they shall all be connected,
at the direction of the City Engineer. No new flared-end pipe sections
shall be allowed to be placed within one hundred (100) feet of an
existing flared-end pipe section, nor will a rip-rap area connection
between pipes be allowed to be installed, unless the discharge separately
into a creek. Instead, an enclosed connection shall be made between
the two (2) pipe sections, the existing flared-end section shall be
removed, area inlets or other means of drainage capture shall be installed
as required, and the area shall be covered and regraded as needed
to ensure that proper drainage for the area continues unabated. The
developer responsible for the new connection shall be responsible
for obtaining all required easements, performing piping installation,
performing grading operations and any/all other work necessary to
achieve this connection.
E.
Plans And Calculations.
1.
General. Plans shall be any scale from one (1) inch equals ten (10) feet through one (1) inch equals one hundred (100) feet so long as the scale is an increment of ten (10) feet. Plans shall be prepared on exhibits nominally twenty-four (24) inches by thirty-six (36) inches. All calculations submitted shall be in accordance with Section 405.100 and shall include the following information:
a.
Site Drainage Map. A drainage map is required and should be
developed from a base reproduction of the site plan or grading plan.
Plans and calculation shall be prepared in accordance to the checklist
pertinent for the type of development (See Title IV Notes: Notes and
Appendixes, Appendix C[2] for application and checklist for compliance with this
Section).
[2]
Editor's Note: Appendix C is on file in the City offices.
b.
Supplemental Drainage Map. A supplemental map may be required
and should be developed from a portion of U.S.G.S. Quadrangie Map.
This map must include the site boundary and the watershed tributary
to the project area.
c.
Surface Drainage. The following information shall be provided
by the developer:
(1)
No sheet flow over one (1) cfs will be allowed
over terraces with slopes that are and/or greater than five (5) feet
in height. Berms and/or swales shall be provided to collect the flow
at the top of the terrace and carry it to a drainage structure. Total
accumulation inside berm and/or swales shall be a maximum of three
(3) cubic feet per second.
(2)
Excluding existing creeks and swales not being
modified by the proposed development, the developer's engineer
shall provide critical cross sections, profiles and hydraulic computations
for ditches and swales with flows in excess of one (1) cfs and creeks
with flows in excess of three (3) cfs.
(3)
Overland Flow Swale. All emergency/overland flow
swales shall be designed on the plans. At all low points on streets,
the flow-line elevation of the swale at the right-of-way line shall
not exceed eight (8) inches higher than the top of the curb inlet
(at said low point). The alternative to this depth is to install a
larger storm pipe, capable of handling the 100-year, twenty-minute
storm.
d.
Location Of Drainage Structures. The lateral location of all
drainage structures shall be shown by street center line stationing
and perpendicular offset distance, and in large lot subdivisions,
by referencing to rear lot line, in addition to the following requirements:
(1)
Inlets shall be appropriately sized and spaced,
taking into consideration by pass, depth of flow and width of spread
of flow in gutters.
(2)
For inlets in vertical sag curves, the center of
the main chambers shall be placed within one (1) foot of the exact
mathematical low point.
(3)
All manholes shall be located outside of the proposed
roadway pavements.
(4)
Inlets shall be located as follows:
(a)
Sump design shall be in accordance to the City
of O'Fallon's adopted street standards.
(b)
Location of area inlets in roadway ditches shall
be compatible with ultimate improvements at an elevation compatible
with the shoulders and sidewalks.
(c)
No driveway shall be closer than six (6) feet from
the edge of a curb inlet.
[R.O. 2008 § 405.240; Ord. No. 6496, 9-13-2018; 7-27-2023 by Ord. No. 7034; Ord. No. 7056, 10-26-2023]
A.
Policy. It is the policy of the City of O'Fallon to protect
and promote the public health, safety and general welfare. The criteria
for stormwater detention will:
1.
Reduce the possibility of damage to public and private property;
2.
Reduce the erosion of land and creek channels;
3.
Assist in the attainment and maintenance of water quality standards;
and
4.
Preserve and enhance the environmental quality of the watercourses
in the City. This criteria provides uniform procedures for designing
and checking the design of storm drainage detention systems.
B.
General Guidelines.
1.
Applicability. This Section shall apply to all development within the corporate limits of the City of O'Fallon, Missouri. Residential developments having a total area of less than five (5) acres and commercial or industrial developments having a total area of less than one (1) acre may be given a waiver by the City in accordance with Article V of this Chapter subject to the following conditions:
a.
The City retains the right to require detention storage in all
cases in which the proposed development will generate excess runoff
that adversely affects the carrying capacity of the receiving watercourse.
b.
Developments less than one (1) acre with less than thirty percent (30%) of the area paved and developments generating less than one (1) cubic foot per second per acre (cfs/acre) increased runoff shall not be required to provide detention storage unless the condition in Subsection (B)(1)(a) above is applicable.
c.
This Section shall apply for all newly platted areas and new
developments proposed after August 17, 1987. All developments that
have an approved preliminary plan by the Planning and Zoning Commission
at the time of the approval of this Section will not have to conform
to this Section.
2.
Affidavit Of Disclosure Of Property Interest. The effective
acreage for a site is not limited to a fractional part of the total.
If a project is developed in phases or small plats, the total acreage
of the project site must be considered. At the time the owner of any
development submits a preliminary plat or preliminary plan, the owner
shall also identify to the City all contiguous property or property
in the watershed that he/she has interest in.
3.
Method Of Evaluation. The storage capacity and discharge rate
shall be based upon the calculated volume and peak flow of the stormwater
runoff, respectively. The calculations for sites having an area of
one hundred (100) acres or less shall be made using either the Soil
Conservation Service Method or the Rational Method. If the site is
larger than one hundred (100) acres, then the engineer shall use the
Soil Conservation Service Method. If another method is desired to
be used, the engineer shall submit a proposed method of evaluation
for the calculations for review and approval. The permitted discharge
rate of stormwater runoff shall be determined by calculating the rate
of runoff for the site's pre- and post-development conditions.
The engineer shall determine the most critical storm looking at three
(3) different time periods:
4.
Detention Of Differential Runoff. All new developments shall provide a stormwater detention facility that insures that the rate of flow of stormwater runoff discharge from the site after development for a two-year, fifteen-year, and 100-year (twenty-minute storm), unless given a waiver by the City in accordance with Article V of this Chapter. Data shall be submitted for the two-, fifteen-, and 100-year frequency (twenty-minute storms).
a.
The highwater elevations for all of the above-mentioned storm
events shall be provided on the plans.
b.
The maximum ponding elevation shall be calculated based on a
routing of the design storm (100-year, twenty-minute) assuming the
lowest outlet is blocked with the water ponded to its maximum elevation.
A minimum of one (1) foot of freeboard shall be provided from the
top of the basin to the maximum ponding elevation.
c.
Any existing development that was approved and accounted for
detention under previous City codes, shall continue to maintain detention
requirements that were applicable at the time, and those former requirements
will continue to be allowed, even if the property use expands (for
example, a building addition, a parking lot addition).
d.
Any redevelopment of a tract of land shall have the current
standards applied to the complete site.
e.
Any undeveloped lot(s) within an existing development (residential
or commercial) that is already covered with detention, under previous
City requirements or as may have been accepted by the City with annexations,
may continue being developed under the previous requirements, unless:
(1)
If the previous requirements are not known or the
existing detention facility calculations cannot to be verified, then
the current detention requirements of the City shall govern for the
improvements for the proposed lot.
(2)
If the existing development does not have detention,
then the current detention requirements of the City shall govern for
the improvements for the proposed lot.
C.
Design Criteria.
1.
General Requirements. The design shall be accomplished under
the direction of a Missouri registered professional engineer. The
design shall also be based on land use in the tributary area as zoned,
actually developed or indicated by an adopted future land use plan,
whichever basis produces the greatest runoff.
2.
Other References. Other agencies have criteria and regulations
pertaining to drainage systems which may complement this criteria.
When conflicts are encountered, the most rigorous criteria shall govern.
a.
FEMA: floodplain regulations and implementing ordinances adopted
by municipalities. Drainage systems designed within the limits of
the designated 100-year floodplain on the principal stream shall be
designed to convey the flood as defined by applicable published floodplain
information studies. For areas located in FIRM Zone "A" outside the
detailed study, the developer shall prepare studies and calculations
establishing the floodplain, elevation and width. These calculations
shall be submitted to the reviewing agencies for approval.
(1)
In the event that a developer desires to place
a basin within an existing floodplain that is to be adjusted via a
FEMA-approved process, then the following process must be followed:
(a)
Developer shall identify the proposed conceptual
new floodplain limits on the plans to be submitted to Planning and
Zoning.
(b)
Obtain conditional Letter of Map Change from FEMA
prior to construction plan approval.
(c)
Approved Letter of Map Change denoting the adjusted
floodplain shall be completed prior to final ten percent (10%) escrow
release for the development. This item will be noted as part of the
construction inspection process.
b.
Missouri Department Of Natural Resources. Rules and regulations
of the Dam and Reservoir Safety Council shall apply to those Missouri
structures classified as dams thereunder.
3.
Stormwater Runoff. The design criteria used in determining the amount of runoff shall be the same as set out in Section 405.230 of this Chapter.
4.
Hydraulic Considerations For Detention Storage.
a.
Principal spillways: shall be designed to meet the following
requirements:
(1)
The principal spillway shall be designed to function
without requiring attendance or operation of any kind or requiring
use of equipment or tools.
(2)
All discharge from the detention facility when
inflow is equal to or less than the 100-year inflow shall be via the
principal spillway(s).
(3)
The design shall allow for discharge of at least
eighty percent (80%) of the detention storage volume within twenty-four
(24) hours after the peak or center of mass of the inflow has entered
the detention basin. On basins less than one hundred (100) acres,
this shall not apply.
(4)
The design discharge rate via the spillway shall
continuously increase with increasing head and shall have hydraulic
characteristics similar to weirs, orifices or pipes.
b.
Emergency Spillways. The emergency spillway shall be provided
to pass a 100-year storm without damaging any property and, where
applicable, designed to DNR dam safety requirements. Overland flow
route will be required to be depicted on the plan for emergency spillways.
c.
Outlet Works. Detention facilities shall have an outlet works
consisting of valves, gates, pipes and other devices as necessary
to completely drain the facility in seventy-two (72) hours or less
when required for maintenance or inspection on normally wet basins.
d.
Sediment Storage. Public detention facilities shall be designed
to provide for five (5) years of sediment accumulation calculated
by using Figure 1 in Appendix D.[1] All other detention facilities shall provide storage for
two (2) years of sediment accumulation by using Figure 1, except for
those using roofs of buildings, paved parking areas or other facilities
designed to preclude the deposition or accumulation of sediment. Sediment
storage volume shall be in addition to the volume required for temporary
storage of stormwater to properly size the detention facility on normally
wet basins.
[1]
Editor's Note: Appendix D is included as an attachment
to this Chapter.
e.
Erosion Control. Principal spillways and outlet works shall be designed to prevent erosion and, if necessary, equipped with energy-dissipating devices to slow the water to normal velocity as called out in Section 405.230(E)(1)(c) of this Chapter. Special measures shall be taken by the developer to not permit sediment from filling the proposed detention basin during all construction of the proposed development unless a design is provided and approved to use the detention basin as a temporary silt basin until such time as the stormwater improvements are completed and the site vegetated.
f.
Public Detention Facilities. As a general rule, detention facilities
shall be private facilities. When determined that a facility shall
be a public facility, the owner shall dedicate the detention facility
and easements with the recording of the record plat, except:
(1)
When multipurpose wet facilities are planned or
are suitable for use for private aquatic recreation or for aesthetic
enhancement of the owner's property.
(2)
When multipurpose dry facilities incorporate surface
recreational improvements.
(3)
Any other means of dedication shall require acknowledgement
and acceptance by ordinance from the City Council.
g.
Private Detention Facilities. Shall be designed requiring the
same criteria as the public detention facilities. The amount of easement
shall be equal to the land occupied by the facility, plus a twenty-foot-wide
strip around the perimeter of the highest elevation attained by the
design storage volume, plus an access easement twenty (20) feet in
width between the facility and the public street. This easement shall
be shown as common ground and be dedicated to the trustees of the
subdivision or owner of the multi-family, commercial or industrial
property for the purpose of maintenance of the stormwater detention
facility, and shall not be part of a residential lot. The easements
as described above shall also be dedicated to the City for emergency
access or periodic inspection. The following items shall be addressed:
(1)
A plan for perpetual maintenance and designating
responsibility for the maintenance shall be provided for its continuing
performance to the standards established by these criteria.
(2)
Underground detention facilities shall also have
the above-mentioned easements provided. Easements shall be labeled
properly on the record plat or by separate document.
h.
Plan Requirements. The plan requirements shall be the same as set out in Section 405.230 of this Chapter with the following additions:
(1)
Elevation-area-capacity curves for the detention
facility, including notation of the storage volumes allocated to runoff
and permanent residual water storage for other uses (wet basins only).
(2)
Inflow hydrograph (detention volumes for Rational
Method) for the two-, fifteen-, twenty-five-, and 100-year recurrence
interval design storms.
(3)
Stage-discharge rating curves for each spillway
and for combined spillway discharges.
(5)
A ten-foot minimum depth for all retention (wet
detention) basins shall be required (per DNR recommendation for healthy
aquatic environment).
(a)
Shallower depth (eight-foot minimum) may be allowed
as long as aeration is provided on the pond.
(6)
All storm sewer pipes shall be labeled as either
"public" or "private" on the storm sewer profile sheets. The transition
structure from public to private shall also be labeled accordingly.
Pipes are not allowed to have said transition outside of a structure.
(7)
For all underground detention facilities, a manhole
(or similar accessible structure) shall be provided both upstream
and downstream [within ten (10) feet or as approved by the City],
for access. Access lids shall be labeled with the words "underground
basin" or similar on each structure. Labels shall be cast into the
lid and be of the same material that is required under storm sewer
design.
(8)
No planting of trees or extensive landscaping shall
be permitted over the top of the underground detention facility, within
the limits of the encompassing easement.
5.
Safety Bench. All retention (wet detention) basins shall have
a safety bench above the normal pool water elevation, with the following
requirements:
a.
Width shall be six (6) feet, starting at where the normal pool
elevation intersects the bank.
b.
Slope of the safety bench shall not exceed 6:1.
c.
The 3:1 slope of the basin banks shall then start at the back
of the safety bench.
d.
Any aquatic bench (defined as a stormwater BMP) being considered
shall be a separate entity from the safety bench.
D.
Construction Alternates. The developer shall build as part of his/her
development a detention facility as required by this Section unless
the following Subsections apply:
1.
If requested by the developer or by the City of O'Fallon, the City, at its option, may waive the construction of a detention facility as for the development. The developer shall seek approval from the City Engineer for the basin to be waived. If the waiver is granted, the developer shall pay an amount equal to the cost of detention for the site as determined by the unit cost as published and updated by St. Louis County. This money is to be used in a stormwater fund for future City stormwater projects. A contractor's bid may be submitted in lieu of using the published data although the bid must be reviewed and approved by the City Engineer prior to acceptance. This option may only be considered if the requirements set out in Subsection (B) above are applicable.
2.
Off-Site/Regional Detention. All detention facilities shall
be on the individual site being developed. The exception to this requirement
is if there is either a regional detention facility identified that
accounts for the subject property being developed, or if the subject
property is a lot within a subdivision plat that accounts for detention.
In any case, if the off-site or regional detention facility does not
fully account for the City's requirements at the time of development,
then supplemental detention may be needed.
a.
On-site detention will be required whenever increased runoff
from the proposed development creates a hazard downstream.
b.
Supplemental detention may be provided by means of modifications
to the off-site or regional basin if feasible. If it is not feasible,
then supplemental detention on-site shall be provided.
c.
If the off-site/regional detention facility is existing at the
time of development, then the developer of the subject property shall
provide approval for use of the detention facility (that also addresses
maintenance responsibility) for said facility, prior to approval.
E.
Inspection, Maintenance And Acceptance By The City Of O'Fallon.
1.
The City Engineer and/or his/her designee shall inspect or cause
to be inspected all stormwater detention facilities constructed within
the City of O'Fallon, Missouri. Through such inspections the
City Engineer and/or his/her designee shall ensure that the facilities
under construction are being constructed in accordance with the approved
plans for such development.
2.
Each owner of the property being developed or has been developed,
whose property has caused the increase in runoff that has necessitated
the need for detention, has the responsibility and duty to properly
operate and maintain any stormwater management system and/or detention
facility, which has not been accepted for maintenance by the City.
The responsibility of maintenance of the system and subdivision projects
shall remain with the developer until such time as the stormwater
management system escrow for such development has been released and
turned over to the homeowner's association or property owner(s)
of record. If there is no active homeowners' association, all
properties listed as part of the subdivision and/or development will
become responsible for maintenance. This will include all underground
detention facilities.
3.
Maintenance responsibility shall remain with the property owner(s) whose said property or development necessitated the need for detention. Regardless of ownership of said basin, should the developer, owner(s), association, or other entity responsible for maintenance choose to sell, abandon, or otherwise vacate their interest or ownership of the basin, this will in no way eliminate their maintenance responsibility of said basin unless they have provided for perpetual future maintenance separately. Said maintenance plan as referenced in Subsection (C)(4)(g)(1) above shall be submitted to the City for approval.
4.
All such privately owned and maintained stormwater systems and/or
detention facilities shall be subject to periodic inspections by the
City Engineer and/or his/her designee. After an inspection by the
City Engineer and/or his/her designee, he/she determines whether or
not the conditions of the privately owned stormwater system and/or
detention facilities are safe and operating and functioning per the
approved plans.
a.
For underground detention facilities, the owner(s) shall be
required to submit an annual maintenance report to the City Engineer
verifying its condition and that it is operating and functioning per
the approved plans. Said inspection shall be performed by a competent
professional who is experienced in this type of work.
5.
If the privately owned stormwater systems and/or detention facility is found to be deficient and in need of compliance measures or maintenance, the property owner(s) will be notified and correction of such requested. Any corrections will be the responsibility as identified in Subsection (E)(3) above. Any cost incurred by the City, as a result of the City Engineer's actions, shall be assessed against the owner(s) of the system. Initially, the stormwater funds as set up in Subsection (D)(2) above may be used to pay for any such emergency authorized by the City.
6.
After notification is provided to the owner(s) of any deficiencies
discovered from an inspection of a privately owned stormwater system
and/or detention facility, the owner(s) shall have thirty (30) days
or other time frame mutually agreed to between the City and the owner(s)
to correct the deficiencies. The City shall then conduct a subsequent
inspection to ensure completion of the repairs. If repairs are not
undertaken or not found to be done properly, then enforcement procedures
following this Section shall be followed.
7.
If, after inspection by the City, the condition of a privately
owned stormwater system and/or detention facility presents an immediate
danger to the public health or safety, because of an unsafe condition
or improper maintenance, the City shall take such action as may be
necessary to protect the public and make the facility safe. Any cost
incurred by the City, as a result of the City Engineer's actions,
shall be assessed against the owner(s) of the system.
a.
No modifications shall be made to any privately owned stormwater
system and/or detention facility, without a permit or other approval
from the City.
8.
Native Vegetation/Natural Basins. Should the owner(s) of a privately
owned stormwater system and/or detention facility want to alter original
construction to convert the system to provide increased water quality
benefits and have a more natural appearance, such alternatives must
be submitted by permit process to the City Engineer or his/her designee
for review of detention facility functionality and approval.
a.
Conversion examples include, but are not limited to, native
grasses, wildflowers, removal of concrete swales, or alteration of
outfall structures.
b.
If approved, the owner(s) shall prepare and submit a maintenance
schedule for the conversion. Modifications will be subject to inspection
during conversion and continue after acceptance.
c.
If approved, converted areas shall be excluded from mowing requirements as stated in Section 220.100, Weeds, but an alternative mowing/maintenance schedule shall be submitted and followed.
(1)
Annual mowing will be required in efforts to prevent the vegetation from becoming excessive and basins from getting overgrown. All conversion-permitted basins shall be mowed by November 1 of each year. Failure to meet this requirement will result in enforcement in accordance with Section 220.100.
e.
Under no circumstances does the altercation from a detention
facility to a native vegetation area waive the requirements for detention.
9.
Upon acceptance of public detention facilities by the City Council,
the stormwater detention facility may be dedicated to the City for
perpetual maintenance. Any such system shall include adequate perpetual
access and sufficient area for maintenance by the City personnel and
vehicles.
[R.O. 2008 § 405.247; Ord. No. 6496, 9-13-2018]
A.
Purpose And Intent. Two (2) consequences
of construction and development are increased runoff created by the
changed properties of ground surface and the rate of discharge of
this increased runoff. These are both of great relevance to stormwater.
The natural condition of the land before development is in relative
balance with the natural capacity of the receiving creeks. Normally,
the undeveloped conditions provide greater permeability and longer
times of concentration. By modification of the ground surface from
the irregular, pervious and vegetation-covered, the areas are changed
to more impervious, more quickly drained and, in some cases, denuded
of vegetation. It is the policy of the City to protect and promote
the public health, safety and general welfare. The management of stormwater
will reduce the erosion on land and creek channels, will reduce the
possibility of damage to public and private property, and will assist
in the attainment and maintenance of water quality standards, and
will preserve the environmental quality of the watercourses in the
City.
B.
Requirements — Creek Bank Setback.
1.
Development along natural watercourses
shall have residential lot lines, commercial or industrial improvements,
parking areas and driveways set back a minimum of twenty-five (25)
feet from the top of the existing stream bank. This is not meant to
prevent access across creeks. Except as otherwise provided herein
or as allowed by the City, the section of land between a natural watercourse
and lot lines shall be designated as common ground and drainage easement
to be maintained by the trustees or owners' association of the subdivision
within all types of developments. Only for non-residential subdivisions
in lieu of the common ground requirement, the section of land between
the natural watercourse and twenty-five (25) feet from the top of
bank can be:
a.
Private property with an easement
dedicated to the trustees or owners' association requiring maintenance
of the areas as the responsibility of the trustees or owners' association;
b.
Private property subject to a conservation
easement in favor of an organization or land trust dedicated to environmental
protection or land preservation such as Trailnet, Inc., the Open Space
Council for the St. Louis Region or similar organization;
c.
Set aside in a stream bank mitigation
program approved by the United States Army Corps of Engineers under
the provisions of the Clean Water Act.
2.
All developments shall maintain a
setback minimum of fifty (50) feet from the top of the existing bank
to any building structure requiring a construction permit that necessitates
excavation or also requires a foundation. Commercial and industrial
areas shall have creek areas dedicated as drainage easements. Notwithstanding
the foregoing setback requirements, an applicant may obtain a variance
to develop within the stream buffer area from the City, provided the
applicant is able to demonstrate that the water quality and stream
morphology will not be adversely affected or adequate mitigation is
provided to offset such adverse effects. Mitigation may include, but
not be limited to, the following:
C.
Post-Construction — Water Quality.
In order to preserve the quality of water in natural streams, it is
important to provide a mechanism to remove contaminants on the site
prior to water entering the natural watercourse. Typically called
post-construction BMPs (best management practices), these methods
identify a critical water quality volume that will need to receive
a treatment to remove certain contaminants. These improvements, whether
structural or non-structural, will remain in place after the construction
is completed. The concepts introduced in the following Subsections
are taken from the Georgia Stormwater Management Manual, Volume 2,
August 2001. Nothing in the following Subsections shall change or
replace any of the City's detention ordinances.
1.
Water Quality Volume (WQv).
a.
The water quality volume (denoted
as the WQv) is the storage needed to capture and treat the runoff
from ninety percent (90%) of the recorded daily rainfall events. In
numerical terms, it is equivalent to one and fourteen hundredths (1.14)
inches of rainfall multiplied by the volumetric runoff coefficient
(Rv) and site area. The WQv is directly related to the amount of impervious
cover created at a site. A minimum WQv of two-tenths (0.2) inches
per acre shall be met at all sites.
b.
Redevelopment projects can appeal
to the Planning and Zoning Commission to reduce or eliminate WQv if
it can be shown that there are stormwater enhancements being provided.
2.
As a basis for determining water
quality treatment volume, the following assumptions may be made:
a.
The water quality volume WQv for
off-site areas is not required. The following equations are used to
determine the storage volume, WQv (in acre/feet of storage):
|
WQv
|
=
|
[(P)(Rv)(A)]/12
|
|
P
|
=
|
1.14 inches of rainfall
|
|
Where:
| |||
|
WQv
|
=
|
Water quality volume (in acre-feet)
| |
|
Rv
|
=
|
0.05 + 0.009 (I) where I is percent
impervious cover
| |
|
A
|
=
|
Area in acres
| |
b.
Measuring Impervious Cover. The measured
area of a site plan that does not have vegetative or permeable cover
shall be considered total impervious cover.
c.
Multiple Drainage Areas. When a project
contains or is divided by multiple drainage areas, the WQv volume
shall be addressed for each drainage area.
d.
Off-Site Drainage Areas. The WQv
shall be based on the impervious cover of the proposed site. Off-site
existing impervious areas may be excluded from the calculation of
the water quality volume requirements.
e.
BMP Treatment. The final WQv shall
be treated by an acceptable BMP(s) from the list presented in this
Chapter.
f.
Extended Detention For Water Quality
Volume. The water quality requirements can be met by providing a twenty-four-hour
draw down of a portion of the water quality volume (WQv) in conjunction
with a stormwater pond or wetland system.
D.
Acceptable Urban BMP Options.
1.
This Subsection sets forth five (5)
acceptable groups of BMPs that can be used to meet the water quality
volume criteria (WQv). The design and selection of these BMPs should
comply with the Georgia Stormwater Management Manual as prepared by
the State of Georgia.
2.
Where the City's criteria or requirements
are more stringent, then they shall govern. Adapting to local Missouri
environment and natural conditions should be expected but shall be
as approved by the City or a higher authority.
The acceptable BMP designs are assigned
into five (5) general categories for stormwater quality control (WQv):
3.
See Section 1.3 of the Georgia Stormwater
Management Manual for additional BMP options. Section 3 of the Georgia
manual has detailed descriptions of each control.
5.
A combination of BMPs and/or credits
is normally required at most development sites to meet all three (3)
stormwater sizing criteria.
a.
BMP Group 1. Stormwater Ponds. Practices
that have a combination of permanent pool, extended detention or shallow
wetland equivalent to the entire WQvs include:
b.
BMP Group 2. Stormwater Wetlands.
(1)
Practices that include
significant shallow wetland areas to treat urban stormwater but often
may also incorporate small permanent pools and/or extended detention
storage to achieve the full WQv include (Modification of existing
wetland areas will require a Corps 404 permit.):
(2)
Wetlands shall not be
used for control of water quantity (i.e., the flood protection volume).
c.
d.
BMP Group 4. Filtering Practices.
(1)
Practices that capture
and temporarily store the WQv and pass it through a filter bed of
sand, organic matter, soil or other media are considered to be filtering
practices. Filtered runoff may be collected and returned to the conveyance
system. Design variants include:
(2)
A maintenance agreement
and maintenance schedule shall be required.
[R.O. 2008 § 405.250; Ord. No. 6496, 9-13-2018; Ord. No. 7015, 4-27-2023]
A.
All buildings, structures and uses of land in the incorporated area
of the City of O'Fallon shall hereafter be required with an adequate,
safe and sanitary disposal system for all human disposal of sewage
or other liquidated wastes and shall conform to the methods outlined
herein:
1.
Where a public sanitary sewer main is reasonably accessible,
in the opinion of the City, the developer shall provide the subdivision
with a complete sanitary sewer system connected with such sewer main,
including a lateral connection for each lot. Such systems and connections
shall comply with the regulations of the Missouri State Board of Health
and Missouri Department of Natural Resources, City of O'Fallon and
the Duckett Creek Sewer District (where applicable).
a.
Sanitary sewer systems outside the City of O'Fallon service
area shall be reviewed and approved by the appropriate sewer district
servicing the area. Approval letters shall be forwarded to the City
of O'Fallon Engineering Department for service areas within the municipal
boundaries.
b.
All sanitary sewer laterals shall be Schedule 40 PVC material.
The wye shall be installed at the same standard as the main.
c.
Developers of commercial or industrial lots shall complete and
submit to the City a sewer pre-treatment survey form.
2.
It shall be the responsibility of the developer/applicant to comply with all requirements of the City of O'Fallon per Chapter 700, and/or Metropolitan St. Louis Sewer District (MSD), latest revision.
3.
Verification of the service shall be provided at the time of
submission of the preliminary plat.
4.
Where no sewers are accessible and no plans for a sewer system
have been prepared and approved, or where the topography restricts
the use of reasonable gravity sewer mains, the developer shall provide
a written engineering alternatives report, signed/sealed by a Missouri
professional engineer, evaluating all of the options to service sewer
for the site. This report should evaluate both gravity and mechanical
options, costs, and maintenance responsibilities of each option, and
provide pros and cons on each. Staff will review options and make
recommendations for this development, and ultimately agree to one
(1) or more of the solutions.
5.
Review By The City's Sewer Consultant. The City's sewer consultant
may be engaged to review the engineering alternatives report. The
sewer consultant's report regarding the analysis will be forwarded
as part of the petitioner's application to the Planning and Zoning
Commission.
6.
Should a mechanical system be the approved alternative, the developer shall either install a sewage collection and disposal system in accordance with the requirements of Subsection (A)(2) above or individual disposal devices may be installed on each lot within the subdivision, provided that no individual disposal device should be permitted unless the lots to be served have sufficient area to allow adequate soil absorption for on-site sewage disposal. The Planning and Zoning Commission may modify lot area requirements in relation to soil conditions and other pertinent facts and findings in any particular subdivision. All such individual devices and systems shall be constructed and maintained in accordance with the regulations and requirements of the Missouri Department of Natural Resources.
a.
If a pump station is being considered in the City's district,
the developer shall use the City's standard design, where applicable.
The City's sewer consultant may be engaged to review any technical
design report or documents pertaining to any final mechanical system.
Any alterations of the City's standard design shall be reviewed and
approved by the City and/or the City's sewer consultant. Said consultant
shall provide recommendations to the City for the final design to
be built with the development.
b.
Any plan for a mechanical system shall be presented to Planning
and Zoning, with the development. A concept level study will be required
at the area plan or preliminary plat stage.
c.
Any mechanical system shall be built in accordance to the City's
requirements in order to provide a reliable system to the public.
7.
For lots with individual water systems and sanitary sewage disposal
systems, the applicant shall adhere to St. Charles County requirements
regarding the minimum lot size.
[R.O. 2008 § 405.260; Ord. No. 6496, 9-13-2018]
A.
Where a public water supply main is reasonably accessible, in the opinion of the City, the subdivision shall be provided with a complete water distribution system adequate to serve the area being platted, including a connection for each lot and appropriately spaced fire hydrants whose locations shall be reviewed and approved by the appropriate fire protection district. The water system shall be designed and constructed per the American Water Works Association (AWWA) standards and guidelines and approved by the City of O'Fallon, per Chapter 700, Public Utilities.
1.
Water systems outside the City of
O'Fallon service area shall be reviewed and approved by the appropriate
water district servicing the area. Approval letters shall be forwarded
to the City of O'Fallon Engineering Department for service areas within
the municipal boundaries.
2.
Where proposed developments are adjacent
to municipal boundaries in the City water district and where fire
flow demands are deficient, or where the area is served with no looped
system, the developer may be required to connect to the outside agency's
water system.
a.
If required, the proposed connection
will be recommended to the City Council as part of the Planning and
Zoning review and approval of the proposed development.
b.
Any hydraulic analysis shall require
the City's model to be updated. The City's water consultant shall
be engaged to review any technical design report or documents pertaining
to any final system layout and to update the model.
B.
For lots with individual water systems
and sanitary sewage disposal systems, the applicant shall adhere to
St. Charles County requirements regarding the minimum lot size.
[R.O. 2008 § 405.270; Ord. No. 6496, 9-13-2018]
A.
All lines for gas, telephone, electrical,
television and other services distributed by wire or cable shall be
placed underground throughout a development. Overhead lines may be
permitted by the Planning and Zoning Commission where it is determined
that such lines will not impair the health, safety, general welfare,
design, appearance and character of the subdivision and only where
such overhead lines are brought to the perimeter of the subdivision.
This Section shall not be construed to prohibit the construction of
aboveground or surface equipment associated with an underground distribution
system, such as (but not limited to) surface-mounted transformers,
power terminal pedestals, meters and meter boxes, concealed wires,
streetlights and streetlight poles.
B.
Utility lines shall be installed prior
to occupancy permits being issued on a particular phase. Utilities
wishing to install utility lines after occupancy permits have been
issued on a particular phase shall be required to obtain a permit
from the City for their excavation.
C.
The City strongly prefers simultaneous
ditching whenever feasible.
[R.O. 2008 § 405.275; Ord. No. 6496, 9-13-2018]
A.
A permit is required for all retaining
walls that are over forty-eight (48) inches tall in height, measured
from the top of the base to the top of the wall or for walls that
support a surcharge load or that alter the channelized drainage of
any lot or drainage area. For retaining walls requiring a permit,
as-built plans are to be prepared by a certified licensed engineer
when required by the Engineering Department.
B.
Retaining walls shall not be placed any
closer to another retaining wall as recommended by a geotechnical
engineer or by a ratio of a minimum of two (2) feet horizontal for
every one (1) foot of vertical height of wall.
C.
Retaining walls in the front yard shall
not exceed a height of four (4) feet and shall be set back a minimum
of ten (10) feet from the front property line or outside the utility
easement, whichever is greater. This requirement can be varied by
the Planning and Zoning Commission or the Board of Adjustment.
D.
Retaining walls in the side or rear yard
shall not be built within two (2) feet from the property line. Retaining
walls in side or rear yards over forty-eight (48) inches will not
be allowed in public utility easements.
E.
Retaining walls will not be allowed in
public rights-of-way without written approval from the City Engineer
and/or his/her designee.
F.
A retaining wall may exceed four (4) feet
in height if it has been designed and engineered by a licensed engineer;
however, any wall shall not exceed six (6) feet in height without
a fence or guard on top.
G.
Any retaining wall more than thirty (30)
inches tall which supports a walking surface that is within two (2)
feet of the wall will require a guard on the retaining wall. The guard
shall be constructed per the current edition of the International
Building Code (IBC) or the International Residential Code (IRC), whichever
is applicable.
H.
Any resident who constructs a retaining
wall within a public utility easement shall be financially responsible
for the removal or reconstruction of the retaining wall, should the
easement be needed, per Missouri law. Refer to the record plat of
the subdivision for easement locations and sizes.
I.
Any construction of a retaining wall requiring
a permit shall include a drainage plan which provides for drainage
around or away from the retaining wall and to be contained on site
or drains to a City-approved location. Stormwater will not be allowed
to flow over the retaining wall.
J.
Retaining walls that alter the channelized
drainage of any lot or drainage area shall not be constructed without
prior approval and permitting from the City of O'Fallon Engineering
Department regardless of the height of the wall.
K.
Any person who wishes to construct a retaining
wall that requires engineering shall submit signed and sealed engineering
plans and calculations for the retaining wall and a site plan showing
the location of the retaining wall to the City of O'Fallon Building
and Code Enforcement Division for review. Upon approval, a building
permit will be issued.
[R.O. 2008 § 405.300; Ord. No. 6496, 9-13-2018]
A.
The following is a list of exemptions in
this Chapter for subdivisions zoned R1-A; all other requirements of
this Chapter must be met:
1.
Culs-de-sac and dead-end streets
of reasonable length [normally not over eight hundred (800) feet]
may be approved where necessitated by topography or where, in the
opinion of the Planning and Zoning Commission, they are appropriate
for the type of development contemplated.
a.
Curb and gutter are not required;
flat-bottom open drainage ditches, approved by the City Engineer and/or
his/her designee, shall be provided in lieu of curb and gutter.
b.
Sidewalks are not required except
in situations where deemed appropriate by the Planning and Zoning
Commission and/or the City Council in order to provide direct access
for pedestrians to recreational areas, common ground, schools, churches,
shopping areas, pedestrianways and multipurpose trails linking adjoining
streets and neighborhoods.
c.
Streetlights shall be required at
all entrances and intersections and shall be provided at a maximum
five-hundred-foot separation.
d.
With the approval of the City Engineer
and/or his/her designee, the maximum grade of a minor residential
street can be increased to fifteen percent (15%) for short stretches
of pavement. A short stretch of pavement is defined as being less
than one hundred fifty (150) lineal feet not counting the curve and
separated by approximately three hundred (300) lineal feet of grades
at ten percent (10%) or less.
e.
With adequate parking on driveways,
pavement width can be reduced to twenty-foot width with three-foot
rock shoulders on each side. No on-street parking would be allowed
in this design. Adequate parking is defined as four (4) for more parking
spaces on each driveway not counting the garage.
B.
If residents of a large lot subdivision
desire to install any of the above improvements, such installation
shall be solely at the expense of property owners of said subdivision.
The City of O'Fallon has no responsibility or obligation to provide
such improvement or to share in such provision. The developer of a
large lot subdivision shall include language to this effect in recorded
restrictions as a condition of record plat approval.
[R.O. 2008 § 405.320; Ord. No. 6496, 9-13-2018; Ord. No. 7015, 4-27-2023]
A.
Streetlights shall be provided in all subdivisions, except as stated under large lot residential subdivisions, Section 405.300. All streetlights shall have underground wiring and meet minimum specifications of the electric utility company serving the area of the proposed subdivision. Streetlights shall be placed at all intersections and in all culs-de-sac. A maximum of three hundred (300) feet separation shall be required, or in special cases a longer separation may be approved by the City Engineer and/or his/her designee. Streetlights shall be installed and functional prior to occupancy of structures within the subdivision.
B.
New Public Streetlight Installations.
1.
Within the City limits, there are multiple electric providers.
The intent is still to have consistent streetlighting City-wide even
though requirements may differ slightly.
a.
In Ameren Missouri's territory, streetlights shall be installed
by the developer in a manner that meets the specifications and rates
for "Service Classification No. 6 (M) Street and Outdoor Area Lighting
— Customer Owned" for unmetered service, seventy-one (71) watt
minimum (LED-Light Emitting Diode) — standard at the energy
and maintenance rate (if applicable, otherwise energy only). The City
Engineer shall prepare more specific details for this specification.
After inspection and acceptance by the City, the lighting facilities
will be maintained and operated by the City. With the developer incurring
the full cost of the light installations and connections, streetlight
billing in new subdivisions shall be turned over to the City for payment
once lights are turned on. Connection fees will be paid to the City
by the developer with the City being responsible for payment of the
connection fee to the utility company when the lights are ready to
be turned on. The City will provide written direction to the electric
company to add new lights to the City's bill. During the period when
an escrow for streetlighting is in place, escrowed funds may be used
for any maintenance expenses incurred or to be incurred by the City.
The standard post top luminaries for the City shall be either the
Early American style or the Colonial style.
b.
In Cuivre River Electric Cooperative's territory, streetlights must be similar in style and installation to the lights noted in Subsection (B)(3) and installed according to Cuivre River Electric Cooperative's requirements. Until a rate is established, for a City-owned post-top light, the installation will be a company-owned light. When a new rate is established for City-owned streetlights similar to Ameren UE's customer-owned rate, streetlight installations shall be made in a manner that closely follows Subsection (B)(3).
2.
All proposed streetlights shall have bulbs that are light-emitting
diode (LED) technology, assuming the electric district has the current
technology available. Any existing bulb shall be replaced with an
LED counterpart when the existing bulb is no longer functional.
3.
All specifications and requirements for the installations of
streetlights shall adhere to the City of O'Fallon Specifications for
the Installation of Streetlights Policy, latest edition. This manual
is available on the City of O'Fallon Engineering website or can be
available by contacting the Engineering Department.
4.
After inspection and acceptance by the City, the lighting facilities
will be owned, maintained and operated by the City. With the developer
incurring the full cost of the light installations and connections,
streetlight billing in new subdivisions shall be turned over to the
City for payment once lights are turned on. Connection fees will be
paid to the City by the developer with the City being responsible
for payment of the connection fee to the utility company when the
lights are ready to be turned on. The City will provide written direction
to the electric company to add new lights to the City's bill.
5.
For any cellular or telecommunications devices that are to be
placed on a streetlight, the owner of the cellular or telecommunications
devices shall assume all electric costs for the light. If the City
is already paying for the electric costs, then that electricity fee
will remain with the City until all cellular or telecommunication
devices are installed and ready to be turned on.
a.
Said streetlight shall remain operational per the City requirements.
Continuous and proper function of the streetlight will be required
as a condition of approval for shared use on the pole. Failure to
meet this requirement could result in the required removal of the
equipment.
b.
Planning and Zoning Commission approval may be required prior
to construction. The applicant shall contact the Director of Planning
and Development for the process.
c.
A separate permit through the City will be required for plan
approval and prior to construction. An agreement may also be required
as part of the terms and conditions of connecting to the pole.
C.
New Private Streetlight Installations. (Streetlights not owned by
the City and typically where a homeowners' association or private
land owner is the customer.)
1.
As an alternative to public-provided streetlights, the subdivision
may opt to have private streetlights (non-City owned/maintained) installed.
Should this option be utilized, the private streetlighting plan must
be approved by the Planning and Zoning Commission with the development.
2.
Lighting on private streets and other areas will not be paid
for by the City.
3.
The City Attorney and Department of Engineering must approve
the language in the covenants and restrictions that provides for the
perpetual payment of streetlighting expenses by the homeowners' association,
in a manner that ensures the lights will always be privately owned,
and not revert to City-owned lights in the future.
4.
The specifications for the private lights as provided for in
this Subsection shall be equal to or better than the City lighting
standards, including the LED requirement, with the exception of the
disconnect as required by the utility company. All proposed streetlights
shall have bulbs that are light-emitting diode (LED) technology, assuming
the electric district has the current technology available. Any existing
bulb shall be replaced with an LED counterpart when the existing bulb
is no longer functional.
D.
This Section pertains to lights on City streets only which are designed
to be dedicated to the City for public use. Lighting on private streets
and other areas will not be paid for by the City and, therefore, this
Section is not applicable to those installations.
[R.O. 2008 § 405.370; Ord. No. 6496, 9-13-2018]
A.
The design of streets shall be designed
in accordance with the latest edition of the Saint Louis County Transportation
Design Criteria for the Preparation of Improvement Plans and the Manual
of Uniform Traffic Control Devices (MUTCD) except as modified by the
City of O'Fallon. Designs shall also incorporate the Traffic Management
Policy as adopted by the City of O'Fallon. All streets shall be constructed
to St. Louis County Highway Standards except as modified by the City
of O'Fallon.
B.
Minimum design requirements shall be as
detailed in the table below.
[Ord. No. 6855, 12-16-2021]
|
Standard Detail Number
|
ROW Width
|
Pavement Width
|
Lane Width
|
Number of Drive Lanes
|
Utility Easement
|
Design Speed
| |
|---|---|---|---|---|---|---|---|
|
Arterial
|
C203.64
|
84
|
63
|
12
|
5
|
10
|
40
|
|
Collector (urban)
|
C203.71
|
60
|
39
|
12
|
3
|
10
|
35
|
|
Collector (residential)
|
C203.84
|
60
|
38
|
n/a
|
2
|
10
|
25
|
|
Minor residential/ Local Access
|
C203.82
|
50
|
26
|
n/a
|
2
|
10
|
25*
|
|
NOTES:
| |
|---|---|
|
*
|
Can be varied with City Engineer's
approval. Minimum posted speed shall be twenty-five (25) miles per
hour.
|
|
These requirements may be varied
by other City ordinances.
| |
|
Narrower pavement widths can be approved following Subsection (C) of this Section.
| |
|
Parkway options can be provided with
the City Engineer's approval.
| |
C.
The above standards are to be considered
minimum standards. Variations in the above standards can be made if
supported by the Director of Planning and City Engineer and further
approved by the Planning and Zoning Commission. Changes must provide
for the health, safety and welfare of the community.
1.
Reduced pavement widths shall be
considered along with a package of enhanced landscaping, enhanced
pedestrian facilities and other community improvements. A traffic
study that includes a parking analysis will be required for projects
requesting reduced pavement widths. The City's Planning Department
will maintain a list of cross sections along with the circumstances
that make the reduced width cross section suitable for the situation.
D.
Center medians can be utilized where left-turn
lanes are not required.
[R.O. 2008 § 405.390; Ord. No. 6496, 9-13-2018]
A.
General Standards.
1.
Street design shall attempt to preserve
existing topography as nearly as possible. Streets shall intersect,
as nearly as possible, at right angles. Street jogs with center-line
offsets of less than one hundred twenty-five (125) feet are prohibited.
2.
Streets will not be approved which
are subject to flooding or frequent inundation.
3.
The system of streets designated
for the subdivision, except in unusual cases, must connect with any
streets already dedicated in adjacent subdivisions; and where no adjacent
connections are platted, must in general be the reasonable projection
of streets into adjacent tracts and must, except in unusual cases,
continue to the boundaries of the tract subdivided, so that other
subdivisions may connect therewith.
4.
The City Engineer may require a street
to be dedicated to public use in order to provide circulation.
B.
The following standards shall apply to
all streets:
|
Maximum Grade
(percent)
|
Minimum Grade
(percent)
|
Radius of Curve
(center)
|
Corner Radii
| |
|---|---|---|---|---|
|
Arterial
|
5%
|
2%*
|
400
|
50
|
|
Collector
|
8%
|
2%*
|
350
|
50
|
|
Residential collector
|
10%**
|
2%*
|
200
|
37
|
|
Minor residential
|
10%
|
2%*
|
150*
|
37
|
|
Cul-de-sac
|
10%
|
2%*
|
150*
|
37
|
|
NOTES:
| |
|---|---|
|
*
|
Can be varied with City Engineer's
approval
|
|
**
|
Some streets within large lot subdivisions may be higher per Section 405.300.
|
|
These standards are minimum standards.
| |
C.
Cul-De-Sac And Stub Streets (Dead-End Streets
To Be Extended In The Future).
1.
In subdivisions with no through streets
where the distance to the through street exceeds one thousand three
hundred (1,300) feet, a fifty-five-foot pavement radius and a sixty-seven-foot
right-of-way radius will be required on at least one (1) cul-de-sac
in order to facilitate school bus circulation.
2.
Cul-de-sac and dead-end streets of
reasonable length may be approved where necessitated by topography
or where, in the opinion of the Planning and Zoning Commission, they
are appropriate for the type of development contemplated.
3.
All culs-de-sac shall have a minimum
right-of-way radius of fifty-four (54) feet and a pavement radius
of forty-two (42) feet. It is advisable to contact the School District
and Fire Department for the minimum radius of the culs-de-sac for
a proposed development prior to submitting plans to the City.
4.
Stub streets over two hundred fifty
(250) feet in length shall have a minimum temporary turnaround pavement
radius of forty (40) feet, covered by a temporary turnaround easement
to remain until the road is extended and platted. In lieu of turnarounds,
the Planning and Zoning Commission may approve a "T"- or "Y"- shaped
paved space on streets which are less than two hundred fifty (250)
feet in length and are planned to be extended in the future.
5.
All stub streets must provide three
(3) standard specification, "Manual on Uniform Traffic Control Devices,"
end of roadway markers mounted on two-pound "U" channel sign posts.
Each marker shall consist of an eighteen-inch diamond reflectorized
red panel. The bottom of each panel shall be mounted a minimum of
four (4) feet above the elevation of the permanent surface and installed
at the terminus of pavement.
D.
Alleys. Alleys, when platted, shall be designated as private. The width, depth and type of pavement shall meet the intended use. The minimum pavement width shall be sixteen (16) feet. Reduced pavement widths can be considered with the same requirements as contained in Section 405.370 for roadways. At a minimum, the pavement shall be six (6) inches of Portland cement concrete. The minimum horizontal radius shall be forty (40) feet at the center line of the alley. The intersection of the alley pavement with the public pavement shall have a minimum thirty-seven-foot radius at the edge of the alley pavement. Alleys shall:
E.
Commercial/Industrial Streets. Commercial/industrial
streets shall have the following design standards:
1.
Commercial and industrial streets
including culs-de-sac shall have a minimum right-of-way width of sixty
(60) feet with thirty-nine (39) feet of pavement. The pavement in
culs-de-sac shall be fifty-five (55) feet in radius with a right-of-way
of sixty-seven-foot-wide radius.
2.
Commercial and industrial arterial
streets shall have a minimum right-of-way of eighty-four (84) feet.
3.
Sidewalks are required on both sides
of commercial streets. Industrial streets may have a sidewalk on one
(1) side of the street if required by the Planning and Zoning Commission.
F.
Sidewalks And Multipurpose Trails.
1.
Sidewalks are required on both sides
of all public and private streets except for:
a.
Single-family residential subdivisions
with an average lot size between one-half (1/2) acre and one (1) acre
shall have sidewalks installed on one (1) side of the street.
b.
Single-family residential subdivisions
with a minimum lot size one (1) acre or larger shall not have sidewalks
required.
c.
Private alleys shall not have sidewalks
required.
d.
A sidewalk is not required on the
side of the street where a multipurpose trail is required in lieu
of a sidewalk.
e.
Cul-de-sac streets shall have sidewalks
installed on both sides of the street with the sidewalk terminating
at the radius of the turnaround.
2.
Sidewalks may be required by the
Planning and Zoning Commission and/or the City Council on one (1)
or both sides of the streets exempted above in order to provide direct
access for pedestrians to recreational areas, common ground, schools,
churches, shopping areas, pedestrianways and multipurpose trails linking
adjoining streets and neighborhoods. The Planning and Zoning Commission
and/or the City Council may limit the requirement of sidewalks to
one (1) side of the street in commercial, office and high-tech developments
that are deemed to likely experience lesser amounts of pedestrian
traffic.
3.
Sidewalk Construction Requirements.
a.
Sidewalks shall have a minimum pavement
width of six (6) feet for arterial and of five (5) feet for collector
streets and four (4) feet for all other streets. Sidewalks constructed
immediately behind the curb shall be a minimum of one (1) foot wider
than said widths.
b.
Sidewalks shall have a lateral slope
of one and one half percent (1 1/2%) with a tolerance of plus or minus
(one half percent) 1/2%.
c.
Sidewalks shall be placed within
the street right-of-way, one (1) foot away from the property line.
d.
Sidewalks shall be constructed of
a minimum of four (4) inches of Portland cement concrete on a compacted
rock leveling course with an average thickness of two (2) inches,
except in driveways where it shall be a minimum of six (6) inches
of Portland cement concrete on a compacted rock base with a minimum
thickness of four (4) inches.
e.
For any sidewalks that are through a driveway apron, refer to Section 405.210 for further requirements.
f.
Accessible curb ramps shall be installed
at all street intersections according to Federal regulations. The
width of the sidewalk shall extend through the curb ramp.
4.
Multipurpose Trails. Multipurpose trails shall be required in lieu of sidewalks where deemed appropriate according to the bike and trail plans approved by the Planning and Zoning Commission and/or the City Council. Multipurpose trails shall have a minimum pavement width of ten (10) feet and shall be constructed of a minimum of three (3) inches of asphaltic concrete on a compacted rock base with a minimum thickness of four (4) inches. Concrete may be used in lieu of asphalt for construction of trails, and shall adhere to the design requirements of Subsection (F)(3) above. Multipurpose trails shall be placed within a minimum twelve-foot-wide trail easement. Accessible curb ramps shall be installed at all street intersections according to Federal regulations. In residential areas, wider-than-normal sidewalks or paths may be utilized as a developer- or builder-selected optional enhancement for the community, but these sidewalks or paths will not be considered multipurpose trails unless they are ten (10) feet wide. The width of the trail shall extend through the curb ramp.
5.
Required fee in lieu of sidewalk
or multipurpose trail installation. If it is determined by the City
Engineer that it would be in the best interest of the City to postpone
the installation of sidewalks and/or multipurpose trails, the adjacent
property owner shall be required to make a cash contribution to the
City (or other applicable government agency) in lieu of the sidewalk
and/or multipurpose trail installation. Said fee shall be calculated
as a fixed amount per lineal foot based on the estimated cost as of
the date that escrows are established. Typically, this estimate shall
be made by the owner's agent and submitted to the City for review
and approval. At a time to be determined by the City, the City will
be required to install sidewalks and/or multipurpose trails on this
property. Once the sidewalk or multipurpose trail fee is paid for
on a particular property, this lot shall no longer be required to
provide a sidewalk or multipurpose trail. The fees collected herein
shall be recorded as revenue in the City's Street and Road Improvement
Fund.
G.
One-Way Streets.
[Ord. No. 7056, 10-26-2023]
1.
For residential streets containing driveways or mailboxes, the
minimum pavement width shall be twenty (20) feet. Parking may be allowed
on one (1) side of the street.
2.
For residential streets that would strictly serve as a corridor,
with no anticipated driveways or mailboxes, or a street that serves
as an entrance to a subdivision with a median separating the lanes
of traffic for a possible entrance monument/sign, the minimum pavement
width shall be thirteen (13) feet, as long as the turn radius at intersections
is sufficient to allow for adequate turning movement. No parking shall
be allowed on these roadways.
3.
The standard pavement typical section shall still be utilized
regarding curbing, thickness, etc.
H.
Private Streets.
[Ord. No. 7056, 10-26-2023]
1.
Private streets shall only be considered for acceptance as a
public street if the street(s) in question serves a public interest,
as determined by the City Engineer.
2.
Before the City will consider accepting the private street as
a public street, a written and signed petition or petitions must be
received from all of the trustees of the subdivision association controlling
the right-of-way, or from all of the right-of-way owner(s) where there
is no subdivision association.
3.
Any right-of-way, easements and building setbacks shall be reviewed.
Any required right-of-way or easements from the owners of the land
shall be donated to the City, and all associated costs shall be borne
by the applicant.
4.
Private streets will only be accepted in their entirety. They
shall never be accepted one-half (1/2) width or less than one (1)
block at a time.
5.
Streets shall have been constructed to meet the specifications
of the current City Code in force at the time of application.
6.
The applicant shall provide all information records about the
street construction and maintenance.
7.
The City Engineer or his/her designee shall inspect for deficiencies
in the street(s). If the City Engineer determines that soil tests
or pavement cores are necessary to accurately assess the condition
of the pavement, the cost of this work, to be completed by a firm
of the City's choosing, shall be borne by the property owner(s)
applying for acceptance of the private street.
8.
The City Engineer or his/her designee will inspect the existing
private street and/or associated storm sewer systems, and will provide
a recommendation to the City Council pertaining to the existing condition.
Prior to the City's acceptance, current City standards for geometry,
roadside safety and right-of-way width, along with identified preventative
maintenance and needed repairs, must be completed. The property owners
of the private street and private storm sewer system will be responsible
for all work necessary to bring the facility into compliance with
the City Engineer's inspection. If accepted, all necessary rights-of-way
and easements will be dedicated to the City in accordance with current
City standards. Any plans to repair or upgrade the private street
and/or storm sewer systems must be submitted to the City Engineer
for review, and any repair or upgrade work must be inspected and approved
by the City Engineer following the same procedures as a new development.
9.
In the event the residents cannot afford to make the improvements
detailed in the City Engineer's inspection, the City Council
may consider forming a Neighborhood Improvement District.
10.
Except where private streets are accepted for public maintenance
under the terms herein, no public funds will be expended for maintenance
operations on private streets and/or private storm sewer systems,
including, but not limited to, snow removal, pothole patching, resurfacing,
storm sewer repairs or the like.
