HomeMy WebLinkAboutWPO201400102 Checklist WPO VSMP 2014-03-05 Swe
Albemarle County Engineering
Erosion and Sediment Control Plan checklist for plan reviewers
5 Mar 2014 (Use the latest checklist from the Team Services engineering forms site)
An erosion and sediment control plan is a document which illustrates the measures used to control erosion
and sedimentation during construction. All measures follow the Virginia Erosions and Sediment Control
Handbook.
Reference key;
[Square Brackets] are County Code references, {Curved Brackets} are policy references, and(regular
parenthesis)are explanatory. Links to reference documents are provided where possible.
Application information:
Completed WPO application and fees,with owners signature [County Code 18-32.4.3.2,
18-32.3.9. 17-203, 17-303] Erosion Control plans require a Water Protection Ordinance
(WPO) application and original owner's signature. No review is provided without
application, owner signature and fees. This is true even for revisions. It is important that
the owner be aware of comments and resubmittals, and this is the county assurance.
Copies of federal and state permits for any wetland or stream disturbance. (Army Corps,
VDEQ, etc) [17-312A,B. 17-319B.D. 17-320C.D, 18-32.1.2, 14-311]
Title informatio i :
'roject title.)Titles should be appropriate. It should be an erosion control plan,not a
. er plan, or site plan, etc. Insome cases a WPO package will contain a
Vgstormwater plan and a mitigation plan,but they should be on separate sheets with keys
and page titles.
Professional seal,with original signature and date for professionally prepared plans.
Content: The erosion control plan must not contain information regarding permanent
improvements that do not also appear on other plans. Erosion control plans are
temporary documents that are discarded after projects are complete.
G�ar� yr kat w Wpo � wkia,-i's heyfi b,uc,(k ►Yovidx. r ,' C atiki
Existing condi ons plan view information: ,►`# i fr .
T accurate current existing topography at the time of itl, inclu��ng all existing site
features, and any recent disturbances, all at a legible scale
date and source of the topographic information: All topography should be at least visually
field verified by the designer within the last year
WPO buffer limits; 100' from stream or wetland bank, 200' from reservoirs, or
floodplain limit if greater.
No buffter disturbances without WPO Program Authority approval and a mitigation
plan.
floodplain limits, including 100yr flood limits for any channel with a drainage area of
50+acres.
Floodplain undisturbed. Disturbances require a Special Use Permit or Floodplain
Development Permit.
all existing eas ments (access, drainage, sight, sanitary easements, etc.)with deed book
references, loc itions and dimensions
all critical slopes (typically shaded)
Zoning Ordinance buffers shown and protected undisturbed. Disturbances require
Planning approval of a waiver.
Albemarle County
Engineering E&SC Plan Checklist
Page 2 of 4
Proposed plan view information:
Gradg:: [18-32.6.2, 14-303]
✓ proposed topography at minimum 2' contour intervals—tied into existing contours, as
well as all proposed site features. (Sites with less than 6' of grade change should consider
✓ using smaller contour intervals.) These should agree with other final plans.
proposed slopes are all 2:1 (horizontal:vertical) or flatter {Design Manual. section 8}
✓ proposed slopes steeper than 3:1 have low maintenance (not grass) ground cover
specified on the plan {Design Manual, Section 8}
,/ existing critical slopes are not disturbed,unless a waiver or exemption has been granted
for the disturbance. [18-4.2, 14-304]
Retaining Wall Plans approved. Any walls supporting roads or necessary infrastructure
require engineered plans (not generic manufacturer's details) and computations. {Design
Manual, section 8} This will also be required where walls are close to property lines and
there is the danger of affecting neighboring property, either during construction,with
later failures, or with pedestrian or vehicle safety.
final contour shapes and slopes ensure no undrained pockets or stagnant pools
Narrative:
narrative and project title (Narratives are now optional, and not reviewed by the County,
other than noting whether they are not seriouly in error, like a boilerplate with another
County's name on it.)
project description
existing site conditions description
adjacent areas description
oft-site areas description including any off-site areas for borroww, waste or other
disturbance.
special use permit for cut ak ater than 50.000cy in.RA zo:ni.ng
soils descriptions
County erosion control notes
stormwater runoff considerations: this can refer to the stormwater management
plan
sediment basin design. computations summary for each sediment basin •
sediment trap design computation summary for each sediment trap
Erosion and sediment control measures:
limits of clearing and grading encompassing all disturbances, entrances, staging and
parking areas, areas where sediment laden runoff will cross, or any construction related
activities. This must match any landscaping and conservation plans submitted with site
plans
✓dconstruction entrance (CE) draining to a sediment trap or basin
ust control symbols (DC)
V temporary and erm t seeding symbols (TS, PS)
�Jexi_ t �drainage divid�a
existing vegetation, with trees to be saved located by drip lines. This must match any
landscaping and conservation plans.
protection provided for all stages/phase of construction,from initial land clearing to
final grades and hardscapes. This is our most important item. Plans which show only
Skiad
Albemarle County
Engineering E&SC Plan Checklist
Page 3 of 4
inlet protection on proposed drainage systems, which are only possible to install upon
completion of grading, should be denied without further review.
no erosion control measures in the way of construction access or grading. Diversion
dikes or silt fence are not placed in the middle of the site, or through access or grading.
Sediment traps are not under or on top of fill material or held up by retaining walls.
Construction entrances are not on fill, etc.If the concept for site protection is not
adequate in this regard,further review of the plan may not be possible.
existing soil boundaries are shown with labels. Areas already disturbed are indicated,
with constructed fill depth or cut noted.
critical erosion areas are identified; areas of constructed slopes, areas near property lines
adjacent off-site disturbances are shown with erosion control facilities
a stockpile location.
where cut or fill balances have a 10,000 cubic yard deficit or more,plans should not be
approved without a waste area identified. This must a on-site, or on another approved and
permitted site. (Don't make the inspectors chase trucks to find the violation.)
a staging and parking area, or other construction related areas
diversion dikes are used to direct drainage to traps and basins
silt fence is not used across contours in place of diversion dikes.
silt fence is limited to areas of sheet flow with '/ acre per 100ft of level on-grade silt
fence. Plans showing only silt fence, without sediment trapping measures, should not be
approved unless they meet this criteria and fill dirt is minimal.
all swales and low points at the perimeter of the site have a sediment trap or basin. Silt
fence in swales is typically not adequate. Check dams do not substitute for traps. If the
concept for site protection is not adequate in this regard,further review of the plan may
not be possible.
temporary slope drains (TSD) or diversions are provided to prevent discharge over
disturbed or fill slopes
inlet protection(IP) on all inlets
culvert inlet protection(CIP) on all culvert inlets
outlet protection(OP) on all outlets
all watercourses are protected and encroachments minimized
stream crossing(USC,SC) and diversions are provided at all stream crossings.
adequate channels(MS-19)provided for each outfall (see Design Manual for minimum
content)
all traps and basins are shown with proposed contours. Simple boxes or symbols are not
sufficient, in most cases, to determine layout or bond amounts.
For each trap;
drainage area is 3 acres or less
sized for total drainage area, including those for in-line upstream facilities
wet storage is 67cy or more
dry storage is 67cy or more
wet storage is 4' deep or less
wet storage side slope is 1:1 or flatter
dry storage side slope is 2:1 or flatter
stone weir is 6ft per acre of drainage area
embankment and stone weir height is 5' maximum from outside toe
embankment top width is adequate (see table 16 reference)
2:1 length:width ratio for flow path
Albemarle County
Engineering E&SC Plan Checklist
Page 4 of 4
For each basin; (GB 3.14)
sized for total drainage area, including those for in-line upstream facilities
wet storage is 67cy or more
dry storage is 67yr or more
wet storage side slope is 1:1 or flatter
dry storage side slope is 2:1 or flatter
embankment 15' high or less from downstream toe
principle and emergency spillways sized per handbook requirements
embankment has 1' freeboard during 25yr storm with emergency spillway
embankment has 2' freeboard during 25yr storm without emergency spillway
trash rack/anti-vortex device specified per handbook requirements
riser anchor size specified per floatation computation
dewatering device sized for 6+hr drawdown of dry storage: 3"dia. minimum
safety fence and signs stating"danger, quick sand, do not enter"provided if near any
residential properties, or public access
structures and embankment match permanent design for facilities to be converted to
permanent stormwater management facilities
embankment top width is adequate (see Design Manual reference details)
2:1 length:width ratio for flow path. If necessary, baffles specified only on temporary
structures (p.III-79)
Details:
a paved construction entrance detail (see Design Manual reference details) for projects in
the development areas over 10 acres
a typical section for each temporary channel or diversion,referenced from the plan
sheets. Existing ground should be shown at the maximum cross-slope on the plan.
details and copies of Program Authority permissions for any variances.
Mass or Early Grading:
mass grading Planning approval. (This is also called rough or early grading plans which
contain only approximate finished grades and culverts necessary to grade) Mass grading
can only be permitted within planned developments where a concept grading plan was
approved with the rezoning. The agent(Director of Planning)needs to formally
determine that the grading plan is in general conformity with the approved rezoning plan.
Otherwise, an initial site plan needs to be approved prior to issuance of a grading permit.
Issuance of a grading permit at the initial site plan stage, as apposed to after final plan
approval,requires specific approval from the County Engineer.
11
Albemarle County Engineering
Retaining Wall Plan checklist for plan reviewers
18 Feb 2014 (Use the latest checklist from the Team Services engineering forms site)
Any walls supporting roads or necessary infrastructure require engineered plans (not generic
manufacturer's details) and computations. {Design Manual, section 8} This will also be required
where walls are close to propert lines and there is the danger of affecting neighboring property,
either during construction,with later failures, or with pedestrian or vehicle safety.
Reference key;
[Square Brackets] are County Code references, {Curved Brackets} are policy references,and(regular
parenthesis)are explanatory. Links to reference documents are provided where possible.
Title information: (applicable to any type of plan)
Project title.
Professional seal, with original signature and date. [18-32.6.1]
Plans :
safety railing shown for retaining walls over 4' high
guardrail with VDOT designations or equivalent shown for retaining walls next to
parking or travelways
VDOT approval for any walls in right-of-way
Accurate depiction of horizontal depth(batter) on site plans.
All structural reinforcement, steal, or geogrids specified.
All dimensions specified
Constructability;there should be no vertical cuts on property lines during construction,
such that abutting property does not become unstable. Adequate room for consruction
needs to be available.
Details and sections :
typical sections with dimensions shown for all configurations
reinforcement layout shown and dimensioned(steel, geogrids, etc.)
details for any pipes through, or bridged utilities, or manholes through geogrid
Computations
Structural computations with original seal and signature for walls over 5' high
Accurate surcharges and loadings assumed
Materials and dimensions match plans
appropriate safety factores used