Sussex
Conservation District Sediment
and Stormwater Management Checklist
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Plan Submittal
Requirements: |
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The following items must be submitted to commence
the review of a sediment
and stormwater management plan: |
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1. Completed application signed by the owner
2. One set of plans and calculations
3. Completed Checklist
4. Review fee |
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If any of the above items have not been provided
or an incomplete stormwater management plan has been submitted the
District reserves the right to return the plan without initiating
the review process. |
Sediment and
Stormwater Notes: |
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The following notes must be provided on the plan
in sequence as shown and without
modifications to the language. |
SS1.____ |
“The Sussex Conservation District must
be notified in writing five (5) days prior to commencing with
construction to schedule a pre-construction meeting. Failure
to do so constitutes a violation of the approved Sediment
and Stormwater Management Plan.” |
SS2.____ |
“Review and approval of the Sediment and Stormwater
Management Plan shall not relieve the contractor from his
or her responsibilities for compliance with the requirements
of the Sediment and Stormwater Regulations, nor shall it relieve
the contractor from errors or omissions in the approved plan.” |
SS3.____ |
“If the approved plan needs to be modified, additional
sediment and stormwater control measures may be required as
deemed necessary by the Sussex Conservation District.” |
SS4.____ |
“The Sussex Conservation District reserves the right
to enter private property for purposes of periodic site inspection.” |
SS5.____ |
“Following soil disturbance or redisturbance-, permanent
or temporary stabilization shall be completed within 14 calendar
days as to the surface of all perimeter sediment controls,
topsoil stockpiles, and all other disturbed or graded areas
on the proposed site.” |
SS6.____ |
"All erosion and sediment control practices shall comply
with the Delaware Erosion and Sediment Control Handbook 1989
or latest edition.” |
SS7.____ |
Specify the responsible party it will be to maintain and
repair all erosion and sediment control and stormwater management
practices during utility installation. |
SS8.____ |
All sediment and stormwater management plans shall contain
certification by the owner or developer of the right of the
Department or delegated inspection agency to conduct on-site
inspections. |
SS9.____ |
A clear statement of defined maintenance responsibility
shall be established during the plan review and approval process. |
SS10.____ |
Include a signed Owner’s Certification that states,
“I, the undersigned, certify that all land clearing,
construction and development shall be done pursuant to the
approved plan and that responsible personnel involved in the
land disturbance will have a Certification of Training at
a Departmental sponsored or approved training program for
the control of erosion and sediment control before initiation
of the project.” This must be signed in ink on each
plan submitted or an original reproducible. Provide the name,
address, and phone and fax number of the owner underneath
the signature. |
SS11.____ |
“Approved plans remain valid for 3 years from the
date of approval.” |
SS12.____ |
“As-built surveys and drawings are to be submitted
to the District within 60-days of stormwater management facility
completion.” |
SS13.____ |
“Approval of a Sediment and Stormwater Plan does not
grant or imply a right to discharge stormwater runoff. The
owner/developer is responsible for acquiring any and all agreements,
easements, etc., necessary to comply with State drainage and
other applicable laws.” |
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G1.____ |
Provide the name, mailing address, phone and
fax number of the owner of the property, the land developer,
the engineer or consultant and the applicant. |
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G2.____ |
Provide the names of adjacent property owners on the plan. |
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G3.____ |
Provide a legend on the Sediment and Stormwater Management
Plan. |
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G4.____ |
Provide a “limit of disturbance” line and the
disturbed area in acres on the plan. |
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G5.____ |
Provide a vicinity map with a scale of 1” = 1 mile. |
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G6.____ |
Provide a north arrow on the plan. |
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G7.____ |
Maximum plan scale of 1”=100’. |
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G8.____ |
Provide tax map |
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G9.____ |
Plans must be submitted on 24”x36” sheets. (Larger
supplemental sheets can be submitted to show a complete overview
of the site’s stormwater management.) |
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G10.____ |
When two or more sheets are used to illustrate the plan
view, an index sheet is required, illustrating the entire
project on one 24”x 36” sheet. |
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G11.____ |
Provide existing and proposed contours based on mean sea
level datum provided at one (1) foot intervals. Contours should
be provided at a minimum 100’ outside the limit of disturbance
line. |
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G12.____ |
For small projects, provide existing and proposed spot elevations
on a 50-foot grid system, based on mean sea level datum, with
high and low points. |
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G13.____ |
State and Federal wetlands must be accurately delineated. |
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G14.____ |
Delineate the National Flood Insurance Program 100 Year
Flood Zone. |
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G15.____ |
Provide soils mapping on plan with a general description
of each soil. Provide the District a copy of the soil survey
with the boundaries of the site delineated. |
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G16.____ |
Delineate streams and drainage ways including, but not limited
tax ditches. |
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G17.____ |
Provide the volume of any spoil or borrow material. |
G18.____ |
All Sediment and Stormwater Management practices shall be
located on the plan. |
G19.____ |
Locate the site benchmark and identify elevation and date. |
G20.____ |
Provide corner and first floor elevations of all buildings,
existing and proposed. |
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ES1.____ |
Provide details and construction specifications
for all erosion and sediment control management practices. |
| ES2.____ |
Projects must be phased so that no more than 20 acres is cleared
at any one time. Grading of the next phase cannot proceed until
temporary or permanent stabilization of the first 20-acre section
is accomplished. |
| ES3.____ |
Stone check dams are required in all swales, ditches and channels.
Provide details, cross-sections and specifications, including
check dam station locations. Check dam depth must be such that
a maximum stone depth is achieved while ensuring that flow continues
over the center of the dam. A minimum 6” depth from the
weir to the top of the structure is required |
| ES4.____ |
All stone, with the exception of check dams, must be underlain
with a geotextile fabric. Geotextile fabric specifications must
be provided for various applications. |
| ES5.____ |
Outlet protection is required at all points of discharge from
pipes, channels and spillways. Provide details, cross-sections
and specification, including d50 stone size, stone depth, outlet
dimensions and type of geotextile fabric. |
| ES6.____ |
Erosion control matting is required on slopes of 3:1 or greater
and in areas of concentrated flow. |
| ES7.____ |
Specify what stabilization measures shall be initiated if
dust control becomes a problem. |
| ES8.____ |
Sediment traps and basins shall be utilized and sized to accommodate
3600 cubic feet of storage per acre of contributing drainage
area until project stabilization is complete. These structures
must be located at the base of the drainage area. The following
information is required: contributory drainage area, top of
slope elevation, bottom elevation, outlet elevation, dimensions,
proposed volume, required volume, storage elevation, clean-out
elevation, type of trap or basin, and dewatering method. |
| ES9.____ |
Diversions must be used to direct run-off into traps. When
sediment-laden stormwater is directed to traps and basins by
closed pipe systems, temporary diversions must be used to direct
stormwater to traps and basins until closed pipe systems are
operational and enough ground cover is achieved to prevent excessive
sedimentation from entering the pipe system. |
| ES10.____ |
Provide a detailed sequence of construction, at a minimum,
include the following actives: clearing and grubbing those areas
necessary for the installation of perimeter controls, construction
of perimeter controls, remaining clearing and grubbing, road
grading, grading for remainder of site, utility installation
and whether storm drains will be used or blocked until after
completion of construction, final grading, landscaping or stabilization,
and removal of sediment control practices. |
| ES11.____ |
Soil stockpile areas must be delineated. Locate stockpiles
on areas with little or no slope. Stockpiles must be surrounded
with silt fence or a stabilized earthen berm. |
| ES12.____ |
Reinforced and/or super silt fence should be utilized in areas
of steep slopes and/or adjacent to sensitive areas such as wetlands,
streams, and drainage ways. |
| ES13.____ |
Provide details of temporary and permanent stabilization measures. |
| ES14.____ |
Specify details of any unusual practices required. |
| ES15.____ |
Provide a single family lot erosion and sediment control detail
and specify in the sequence of construction that home construction
is to take place after stormwater facilities have been constructed
and stabilized. |
| ES16.____ |
Provide specific notes and details on dewatering practices. |
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| SM1._____ |
Provide a stormwater management narrative. Include
in the narrative pictures of the current conditions of the site,
the proposed outfall location and any unusual site features. |
| SM2._____ |
Provide existing and proposed drainage area maps that include
the entire contributory drainage area. |
| SM3._____ |
Sub-watershed areas must be delineated on the plan for both
the pre- and post-development conditions. Clearly show the “Tc”
path, slope, and soils in each sub-watershed and provide the
area in acres. |
| SM4._____ |
Provide directional stormwater flow arrows for all existing
and proposed channels, pipes, etc. |
| SM5._____ |
Provide inlet and outlet invert elevations for all drainage
structures and facilities. |
| SM6._____ |
Provide profiles for all outfall pipes and channels. |
| SM7._____ |
Provide runoff calculations considering off-site contributing
drainage. Provide pre- and post-development velocities, peak
rates of discharge, and inflow and outflow hydrograph of stormwater
runoff at all existing and proposed points of discharge from
the site for the two (2) year, ten (10) year and the (100) year
storm. Show site conditions around points of all surface water
discharge including vegetation and method of flow conveyance
from the land disturbing activity and design details for structural
controls. |
| SM8._____ |
All hydrologic computations shall be
accomplished using the most recent version of USDA Soil
Conservation Service TR-20 or TR-55, with the Delmarva Unit
Hydrograph. The storm duration for computational purposes shall
be the 24-hour rainfall event. The pre-development peak
discharge rate shall be computed assuming that all land used in
the site to be developed are in good hydrologic condition. |
| SM9._____ |
Provide cross-sections and specifications for
diversions, ditches, ponds, swales, infiltration structures,
etc. |
| SM10._____ |
Post-development peak rates of discharge for
the 2- and 10-year frequency storm events shall not exceed the
pre-development peak rates of discharge for the 2- and 10-year
frequency storm events. |
| SM11._____ |
Water quality ponds having a permanent pool shall be designed
to release the quality storm runoff over a 24-hour period. Practices
not having a permanent pool shall be designed to release the
first inch of runoff from the site over a 24-hour period. |
| SM12._____ |
Infiltration practices, when used, shall be designed to accept,
at least, the first inch of runoff from all streets, roadways,
and parking lots, (including all contributing drainage areas). |
| SM13._____ |
All stormwater designs shall be in accordance with standards
developed and/or approved by the DNREC. |
| SM14._____ |
Maintenance set aside areas for disposal of sediments removed
from stormwater management facilities must be provided. Set
aside areas shall accommodate at least 2% of the stormwater
management facility volume to the elevation of the 2 year storage
volume elevation, maximum depth of the set aside volume shall
be one foot, and the slope of the set aside area shall not exceed
5%. |
| SM15._____ |
All ponds shall have a forebay or other design feature to
act as a sediment trap; a ten (10) foot reverse slope bench
must be provided one foot above the normal pool elevation for
safety purposes; a ten (10) foot level bench one foot below
the normal pool elevation, and all embankment ponds having a
permanent pool shall have a means to drain the pool. (Alternatively,
see attached Safety Memo from DNREC.) |
| SM16._____ |
When bioswales are proposed the following information should
be addressed: |
a.) |
Design subcatchments so runoff from the contributory drainage
area is captured and conveyed to the swale at the up-stream
end. When computing the “tc” path of subcatchment,
do not use any length of flow which occurs in the bioswale itself.
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b.) |
Use Manning’s “n” value .2 or .24. |
c.) |
The design depth should be 50% the height of the anticipated
winter grass height. |
d.) |
Minimum length of swale is 100’ and the width cannot
exceed 8 feet. |
e.) |
Residence time of 9 minutes is required. |
SM17._____ |
Infiltration practices shall be used only
when the following criteria can be met or exceeded: |
a.) |
Areas draining to these practices must
be stabilized and vegetative filters established prior to
runoff entering the system. |
b.) |
A suspended solids filter accompanies the
practice; when vegetation is used, there shall be at least
a 20-foot length of vegetative filter. |
c.) |
The bottom of the infiltration practice
is at least three feet above the seasonal high water table.
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d.) |
The infiltration practice shall be designed
to drain completely within 48 hours for the 10-year storm. |
e.) |
Infiltration practices are limited to soils
having an infiltration rate of at least 1.02 inches per hour
as determined by a single-ring infiltrometer test. One site
soil borings and textural classifications must be done to
verify site conditions and seasonal high water table; this
information must be submitted with the plan. The design infiltration
rate shall by ½ the measured infiltration rate. |
f.) |
Infiltration practices greater than three
feet deep shall be located at least 20 feet from basement
walls. |
g.) |
Infiltration practices designed to handle
runoff from impervious parking areas shall be a minimum of
150 feet from any public or private water supply well. |
h.) |
Infiltration practices shall have overflow
systems with measures to provide a non-erosive velocity of
flow along its length and at the outfall. |
i.) |
The slope of the bottom of the infiltration
practice shall not exceed five percent. |
j.) |
Infiltration practices shall not be installed
in fill material. |
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| SP1._____ |
The Stormwater ponds for proposed Stormwater management
shall be designed and constructed in accordance with U.S.D.A,
Soil Conservation Service Small Pond Code 378, dated September
1990, as approved for use in Delaware. At the minimum, specify
the type of acceptable pond embankment material, placement methods
and depth of each fill lift, required compaction density and
moisture content of fill, type of compaction equipment to be
used, etc. It is required that all fill placement for the embankment
must be tested, approved, and placed under the supervision of
an experienced soil scientist/technician. A geotechnical report
is to be submitted to the District upon completion. |
| SP1._____ |
Provide the District with a foundation investigation required
per Pond Code 378. As a minimum, it shall include information
along the centerline of the proposed dam, the emergency spillway
location, and the planned borrow area. The extent of the investigation
will vary from site to site. All investigations shall be logged
using the Unified Soil Classification System. Describe methods
to be used to dewater the foundation area so that fill material
can be properly placed and compacted in the cutoff trench and
across the embankment foundation. |
| SP1._____ |
Provide a minimum three (3) square feet of sectional area
if the principal spillway is to be used to pass the 100-year
storm. |
| SP1._____ |
The cutoff trench shall begin at a minimum of 4 feet below
existing ground. The cutoff shall extend into the abutments
to the peak elevation of the 10-year storm and be deep enough
to extend into a relatively impervious stable foundation. Provide
the extent of the cutoff trench on the plan view. Side slopes
for the trench are to be 1H to 1V. |
| SP1._____ |
The design height of the dam shall be increased by the amount
needed to ensure that after settlement the height of the dam
equals or exceeds the design height. |
| SP1._____ |
The construction specifications for Pond Code 378 need to
be on the plan (refer to construction specs in the sequence.) |
| SP1._____ |
All anti-seep collars and their connections to the conduit
shall be watertight and the collar must be made of material
compatible with the conduit. Provide a detail for the anti-seep
collar on the plan. |
| SP1._____ |
When fill is placed to create the pond banks one (1) foot
of freeboard must be provided between the crest elevation of
the 100-year storm and the top of bank of the pond. |
| SP1._____ |
Ponds constructed by a combination of both the excavation
and the embankment methods are classified as embankment ponds
if the depth of water impounded against the embankment at spillway
elevation is three (3) feet or more. |
| SP1._____ |
Emergency spillways shall be trapezoidal and located in undisturbed
earth. |
| SP1._____ |
For ponds with a permanent pool, ½” of volume
must be provided below the level of the permanent pool to allow
for settling of sediments in the quality storm. |
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All final
plans submitted to the District for approval should have the following. |
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A1._____ |
All plans submitted for approval shall be sealed
the design professional. |
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A1._____ |
Owner’s Certification must be signed in ink. |
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A1._____ |
Approval letter from DelDOT and or municipality for discharging/connecting
to stormwater system. |
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A1._____ |
NOI must be submitted to DNREC. |
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A1._____ |
Provide approval letter from DNREC Drainage Section for any
encroachment or change in runoff discharge to existing tax ditch
or adjacent right-of-way. |
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A1._____ |
Wetland permit when construction of stormwater facility will
impact State/Federal wetlands. |
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A1._____ |
Copy of recorded permanent easement when stormwater facility
or outfall is located outside of property boundary. |
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* Each and
every one of the above items applicable should be included in the
Sequence of Construction or general notes.
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