HomeMy Public PortalAboutCity of WildwoodCity of Wildwood, MO
Friday, March 19, 2021
Chapter 425. Grading
Section 425.050. Standards Safety Precaution.
[R.O. 1997 § 425.050; Ord. No. 207 § 5, 2-26-1996; Ord. No. 221 § 3, 4-8-1996;
Ord. No. 1488 § 1, 2-25-2008]
A. All grading shall comply with the following requirements:
1. Surface Waters —Damage. Adequate provision shall be made to prevent
any surface waters from damaging the cut face of an excavation or the
sloping surface of a hill.
2. Retaining Walls —Cribbing. Retaining walls or cribbing shall be required
whenever deemed necessary by the Department of Public Works to
prevent the surface of any excavation or fill from exceeding at any point
the maximum allowable slopes as set forth herein.
3. Drainage. All drainage provisions shall be of such design to carry surface
waters to the nearest practical storm drain or natural watercourse as
approved by the Director of Public Works as a suitable place to deposit
and receive such waters. Where possible, water shall be dispersed by
convex surfaces to dissipate water energy and velocity and disperse
volume over a greater surface area before being carried to a storm drain
or watercourse.
4. Protection Of Streets, Property. No excavation shall be made so close to
the property line to endanger any adjoining public or private street
without supporting and protecting such public or private street or property
from settling, cracking or other damage.
5. Fill Location. No fill shall be made so as to cause or to allow the same to
be deposited upon or to roll, flow or wash upon or over the premises of
another without the express written consent of the owner of such
premises so affected; or upon or over any public street, walk, place or
way; nor so close to the top of a bank of a channel as to create the
possibility of bank failure and sliding.
6. Materials. Materials for fills shall consist of material obtained from
excavation of banks, borrow pits or other approved source. Material shall
consist of clean uncontaminated earth, soil, dirt, sand, rocks, gravel or
masonry materials only, shall be free of vegetable matter and deleterious
material and shall not contain large rocks or lumps. Materials for
roadways are not covered by this Chapter as per exceptions in Section
425.030.
7. Minimum Standards. Minimum standards of excavations and fills shall be
as follows:
a. No excavation shall be made with a cut face steeper in slope than
three (3) horizontal to one (1) vertical.
b. No fill shall be made which creates an exposed embankment face
steeper in slope than three (3) horizontal to one (1) vertical. The
embanked end of the fill shall be uniformly compacted as provided in
Subsection (A)(8) hereof and stable under the proposed conditions.
8. Minimum Standards —Land Disturbance. Unless modified as may be
permitted in this Subsection (A)(8) or by provisions of Subsection (A)(9)
(b) hereof, minimum standards for land disturbance shall be as follows:
a. No land disturbance shall occur within fifty (50) feet of any creek,
stream, water runoff channels or ravines or in other areas
determined by the Director or his/her designees to be highly
sensitive or subject to erosion or flooding, except as necessary for
construction pursuant to an approved final site plan, planned zoning
development, or conditional use permit specifically authorizing the
modification of this standard and necessitating exception to this
minimum standard.
b. No land disturbance shall occur on terrain that does not satisfy the
minimum standards for excavation or fill, except as necessary for
construction pursuant to an approved final site plan, planned zoning
development, or conditional use permit specifically authorizing the
modification of this standard and necessitating exception to this
minimum standard.
c. No land disturbance shall occur on any property or lot line or within
the area of building setback required by applicable zoning or
subdivision regulations, except as necessary for construction
pursuant to an approved final site plan, planned zoning
development, or conditional use permit, or approved subdivision plat
specifically authorizing the modification of this standard and
necessitating exception to this minimum standard.
d. No land disturbance shall occur which shall cause a nuisance to any
adjoining property owner, or which shall violate any Federal, State or
local law or regulation. The Director of Public Works, in conjunction
with the Department of Planning, shall establish regulations for the
granting of permits so as to enforce this Chapter and ensure that
any grading is completed with minimum erosion, aesthetic
degradation or other negative impact on the site or surrounding
areas or the community.
e. Clearing techniques that retain existing vegetation to the maximum
extent practicable shall be used and the time period for disturbed
areas to be without vegetative cover shall be minimized to the extent
practical.
f. Clearing, except that necessary to establish sediment control
devices, shall not begin until all sediment control devices have been
installed and have been stabilized.
9.
Phasing shall be required on all sites disturbing greater than thirty
(30) acres of land. The size of each phase will be established by the
Department of Public Works at the time of plan review for the
issuance of a grading permit.
h. The Director of Public Works, in conjunction with the Department of
Planning, shall establish such other minimum standards as may be
necessary to protect grand trees or specimen vegetation or land
features or to otherwise effect the purposes of this Chapter.
9. Minimum Standards—AII Grading.
a. All grading shall comply with the restrictions and prohibitions set
forth in the Natural Resource Protection Standards of the
Subdivision Code (see Chapter 420), all requirements of the Tree
Preservation and Restoration Code (see Chapter 410 of this Code),
and other applicable zoning (see Chapter 415) and subdivision
regulations (which are on file in the City offices) pertaining to the site
or development. No grading permit shall be issued on any site
where there is an existing uncured violation of any provision of the
zoning, subdivision or other development regulations of the City of
Wildwood.
b. Modifications. Any party seeking a permit may request a
modification of any of the minimum standards set forth in Subsection
(A)(7) or (8) hereof by filing a written request with the Director
specifically identifying:
(1) Unique or unusual characteristic(s) of the site, not generally
applicable, that eliminate the need for full application of the
standard, or
(2) The precise mitigation proposed that would fully rectify the
harms addressed by the minimum standard to be modified.
The Director may make such modification upon a
determination that such facts exist qualifying for such
modification; provided that no modification shall be permitted
that shall circumvent any other applicable regulation or the
intent of these minimum standards to eliminate the detrimental
impact of grading addressed by each such standard.
c. Erosion Control Design. Erosion control requirements shall include
the following:
(1) Soil stabilization shall be completed within five (5) days of
clearing or inactivity in construction.
(2) If seeding or another vegetative erosion control method is used,
it shall become established within two (2) weeks or the site shall
be reseeded or a non -vegetative option employed.
(3) Techniques shall be employed to ensure stabilization on steep
slopes and in drainageways.
(4) Soil stockpiles must be stabilized or covered at the end of each
workday or perimeter controls must be in place to prevent silt
from the stockpile from leaving the site.
(5) The entire site must be stabilized, using a heavy mulch layer or
another method that does not require germination to control
erosion, at the close of the construction season. No new
grading shall commence after the close of the construction
season and before the start of the next construction season,
unless authorized by the Director of Public Works in accordance
with Section 425.050(A)(9)(b) of this Chapter; except for
minimum necessary grading for the foundation or basement of
any building, structure or swimming pool for which a building
permit has been duly issued.
(6) Techniques shall be employed to prevent the blowing of dust or
sediment from the site.
(7)
Techniques shall be employed to divert upland runoff past
disturbed slopes.
d. Sediment Control Design. Sediment control requirements shall
include:
(1) Settling basins, sediment traps or tanks and perimeter controls.
(2) Settling basins shall be provided for each drainage area within
ten (10) or more acres disturbed at one time and shall be sized
to contain one-half (0.5) inch of sediment from the drainage
area and be able to contain a two-year, 24 -hour storm. If the
provision of a basin of this size is impractical, other similarly
effective best management practices (BMP), as evaluated and
specified in the Storm Water Pollution Prevention Plan
(SWPPP), shall be provided.
Settling basins shall be designed in a manner that allows
adaptation to provide long-term stormwater management as
required by the City.
(3)
(4) Settling basins shall have stabilized spillways to minimize the
potential for erosion of the spillway or basin embankment.
Protection for adjacent properties by the use of a vegetated
buffer strip in combination with perimeter controls.
(5)
e. Watercourse Design. Watercourse protection requirements shall
include:
(1) Encroachment into or crossings of active watercourses/riparian
areas and wetlands shall be avoided to the maximum extent
practicable. All City, State and Federal permits and approvals
shall be obtained by a permit holder prior to beginning work
authorized by a City grading permit.
(2) Stabilization of any watercourse channels before, during and
after any in -channel work.
If a defined watercourse is to be realigned or reconfigured,
clearing and grubbing activities within fifty (50) feet of the
watercourse shall not begin until all materials and equipment
necessary to protect the watercourse and complete the work
are on site. Once started, work shall be completed as soon as
possible. Areas within fifty (50) feet of the watercourse shall be
recontoured and revegetated, seeded or otherwise protected
within five (5) working days after land disturbance activities
have ceased.
(3)
(4) All stormwater conveyances shall be designed according to the
criteria of the St. Louis Metropolitan Sewer District (MSD) and
the necessary MSD permits obtained.
(5) Stabilization adequate to prevent erosion shall be provided at
the outlets of all pipes and paved channels.
f. Construction Site Access Design. Construction site access
requirements for land disturbance greater that one (1) acre shall
include:
(1) A temporary access road provided at all grading sites including
a wash down area supporting all active sites.
(2) The Department of Public Works may require other measures to
ensure that construction vehicles do not track sediment onto
public streets or be washed with wash effluent channeled
directly into storm drains.
10. Compaction. All fills intended to support buildings or structures, sewers
and conduits shall be compacted to a minimum of ninety percent (90%)
compaction as determined by Modified Proctor, ASTM D-1775.
Compaction of fills for these uses must be certified by a registered
professional engineer at the owner's expense. Frequency of compaction
tests is to be determined by the Director of Public Works. Compaction of
other fills shall be required where necessary as a safety measure to aid
in preventing the saturation, slipping or erosion of the fill. The
requirements of the Director of Public Works for the compaction of fills
shall include, but shall not be limited to, the following:
a. Areas to be graded by cutting or filling shall be rough graded to
within two -tenths (2/10) of a foot of accepted elevation after
allowance has been made for thickness of topsoil, paved areas and
other installations.
b. The natural ground surface shall be prepared by removing topsoil
and vegetation and by compacting the fill upon a series of terraces.
Hillside or slope fills shall require plowing or scarification of original
ground.
c. Grading of slopes will require silt fencing at intermediate levels to
slow surface water, prevent rutting and decrease erosion.
d. Grading sites will require silting basins to prevent mud from washing
onto adjacent properties.
e. If fill material moisture content is below the requirement for
compacting to maximum practical density, water in the proper
amount shall be added. If moisture content is too great, fill material
shall be aerated by blading or other satisfactory methods to reduce
moisture content.
f. Frozen materials or soft, mucky, friable, easily compressible
materials shall not be incorporated in fills intended to support
buildings, structures, sewers or conduits or in the embanked ends of
fills. In heavy rain, interrupted work shall not be resumed until
moisture content is satisfactory. Fill material shall not be placed,
spread or rolled while the ground is frozen or thawing.
g.
The maximum uncompacted thickness of layers of the fill to be
compacted shall not exceed eight (8) inches.
h. Compaction shall be by tamping, sheepsfoot rollers, multiple wheel
pneumatic or other type rollers. Rolling shall be continuous until the
desired maximum density is obtained.
i. Topsoil disturbed by grading or building operations shall be stripped
and piled for storage in an amount necessary to complete finished
grading only.
11. Removal Of Timber, Rubbish, Etc. Timber, logs, trees, brush, vegetable
matters and rubbish of any description shall be removed and disposed of
so as to leave the disturbed area with a neat and finished appearance.
Tree stumps, masonry and other obstructions shall be removed to the
following depths:
Paved areas —Two (2) feet below subgrade
Lawn areas —Two (2) feet below finished grade
Solid rock, shale or similar materials shall be removed to a depth of
fifteen (15) inches below subgrade for paved area and two (2) feet
below finish grade for lawn area except where it is impractical because
of rock outcropping.
12. Storm Water Pollution Prevention Plan (SWPPP) Required For Land
Disturbance Greater Than One Acre In Area. All applications for grading
permits for land disturbance greater than one (1) acre in area shall be
accompanied by a Storm Water Pollution Prevention Plan (SWPPP)
prepared for the specific site by or under the direction of a qualified
professional. The application shall contain a statement that any land
clearing, construction or development involving the movement of earth
shall be in accordance with the Storm Water Pollution Prevention Plan
and the applicant will assume and acknowledge responsibility for
compliance with this Code and the Storm Water Pollution Prevention
Plan at the site of the permitted activity.
a. Content. The Storm Water Pollution Prevention Plan (SWPPP) shall
comply with the standards established herein and shall include the
following:
(1) Name, address and telephone number of the site owner and the
name, address and telephone number of the individual who will
be in overall responsible charge of construction/development
activities at the site.
(2) Site address or location description and parcel identification
number(s).
A site map showing the outlines of the total project area, the
areas to be disturbed, existing land uses, locations and names
of surface water bodies, locations of flood plains, locations of
temporary and permanent best management practices (BMP)
and such other information as may be required by the City.
(4) Existing contours of the site and adjoining strips of off -site
property and proposed contours after completion of the
proposed land disturbance and development, based on United
(3)
States Geological Survey datum, with established elevations at
buildings, walks, drives, streets and roads; and information on
necessary clearing and grubbing, removal of existing structures,
excavating, filling, spreading and compacting.
(5) A natural resources map identifying soils, forest cover and
resources protected under other provisions of City ordinances.
(6) An estimate of the runoff coefficient of the site prior to
disturbance and the runoff coefficient after the construction
addressed in the permit application is completed.
(7) Estimated quantity of land to be disturbed.
(8) Details of the site drainage pattern both before and after major
land disturbance activities.
(9) Access to construction site.
(10) Description of best management practices (BMP) to be utilized
to control erosion and sedimentation during the period of land
disturbance.
(11) Description of best management practices (BMP) to be utilized
to prevent other potential pollutants such as construction
wastes, toxic or hazardous substances, petroleum products,
pesticides, herbicides, site litter, sanitary wastes and other
pollutants from entering the natural drainageways during the
period of construction and land disturbance.
(12) Description of best management practices (BMP) that will be
installed during land disturbance to control pollutants in
stormwater discharges that will occur after land disturbance
activity has been completed.
(13) Location of temporary off-street parking and wash down area
for related vehicles.
(14) Sources of off -site borrow material or spoil sites and all
information relative to haul routes, trucks and equipment.
(15) The anticipated sequence of construction and land disturbance
activities, including installation of best management practices
(BMP), removal of temporary best management practices
(BMP), stripping and clearing; rough grading; construction
utilities, infrastructure and buildings; and final grading and
landscaping. Sequencing shall identify the expected date(s) on
which clearing will begin, the estimated duration of exposure of
cleared areas, areas of clearing, installation of temporary
erosion and sediment control measures and establishment of
permanent vegetation.
(16) All erosion and sediment control measures necessary to meet
the objectives of this code throughout all phases of construction
and after completion of site development. Depending upon the
complexity of the project, the drafting of intermediate plans may
be required at the close of each season.
(17) Seeding mixtures and rates, types of sod, method of seedbed
preparation, expected seeding dates, type and rate of lime and
fertilizer application and kind and quantity of mulching for both
temporary and permanent vegetative control measures.
(18) Provisions for maintenance of control facilities, including
easements and estimates of the cost of maintenance.
(19) Plans for responding to any loss of contained sediment to
include the immediate actions the permit holder will take in case
of a containment failure. This plan must include documentation
of actions and mandatory reporting to the Department of Public
Works.
(20) Schedules and procedures for routine inspections of any
structures provided to prevent pollution of stormwater or to
remove pollutants from stormwater and of the site in general to
ensure all best management practices (BMP) are continually
implemented and are effective.
b. Required Plan Amendments —Storm Water Pollution Prevention
Plan (SWPPP). The permit holder shall amend the Storm Water
Pollution Prevention Plan whenever:
(1) Design, operation or maintenance of best management
practices (BMP) is changed;
(2) Design of the construction project is changed that could
significantly affect the quality of the stormwater discharges;
(3) Site operator's inspections indicate deficiencies in the Storm
Water Pollution Prevention Plan (SWPPP) or any best
management practices (BMP);
(4) Inspections by City or by the Missouri Department of Natural
resources indicate deficiencies in the Storm Water Pollution
Prevention Plan (SWPPP) or any best management practices
(BMP);
The Storm Water Pollution Prevention Plan (SWPPP) is
determined to be ineffective in significantly minimizing or
controlling erosion or excessive sediment deposits in streams or
lakes;
(5)
(6) The Storm Water Pollution Prevention Plan (SWPPP) is
determined to be ineffective in preventing pollution of
waterways from construction wastes, chemicals, fueling
facilities, concrete truck washouts, toxic or hazardous materials,
site litter or other substances or wastes likely to have an
adverse impact on water quality;
(7)
Total settleable solids from a stormwater outfall exceeds one-
half (0.5) ml/L/hr if the discharge is within the prescribed
proximity of a valuable resource water as defined by the
Missouri Department of Natural Resources;
(8) Total settleable solids from a stormwater outfall exceeds two
and one-half (2.5) ml/L/hr for any other outfall; or
(9) The City or the Missouri Department of Natural Resources
determines violations of water quality standards may occur or
have occurred.
c. Permit Holder Responsibilities For Administration Of Storm Water
Pollution Prevention Plan (SWPPP). The permit holder shall:
(1) Notify all contractors and other entities (including utility crews,
City employees or their agents) that will perform work at the site
of the existence of the Storm Water Pollution Prevention Plan
(SWPPP) and what actions or precautions shall be taken while
on site to minimize the potential for erosion and the potential for
damaging any best management practices (BMP);
(2) Determine the need for and establish training programs to
ensure that all site workers have been trained, at a minimum, in
erosion control, material handling and storage and
housekeeping;
Provide copies of the Storm Water Pollution Prevention Plan
(SWPPP) to all parties who are responsible for installation,
operation or maintenance of any best management practices
(BMP); and
(4) Maintain a current copy of the Storm Water Pollution Prevention
Plan (SWPPP) on the site at all times.
(3)