HomeMy WebLinkAbout03008 - Technical Information Report - Drainage BAIMA & HOLMBERG INC.
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DRAINAGE REPORT
for
Malea Short Plat
Apri129,2003
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E�PIRES 11/30/04
Baima & Holmberg, Inc. Job No. 2016-003
Prepared For
Pat Anardi
PO Box 58233
Renton, WA 98058-1233
100 FRONT STREET SOUTH • ISSAQUAH • WASHINGTON • 98027-3817 • (425) 392-0250 • (425)391-3055
Project Overview
This project involves the short platting of a 0.35-acre parcel into 3 single-family �
lots. The site is located on the west side of Davis Avenue South between South �
15�' Street and South 17�' Street (e�ended). The site currently has a house, ''
garage, driveway and lawn. The site slopes down to the west at about 5%.
Downstream Drainage '
The site sheet flows west across the neighboring, undeveloped, grass covered
property, about 200' to a swallow, flat ditch along the east side of Lake Avenue
South. Runoff flows south along the ditch, crossing west through a 12" culvert to
a catch basin along the west side of the road. A pipe from the Catch basin
continues west between a couple of houses, down the hill overlooking SR167.
There are no obvious drainage problems along this downstream drainageway.
Drainage Control
Because th
K WDM Core Requirement# 1, the roofs and private driveway runoffwill be
picked up in a catch basin/pipe system and dispersed at the west property line, its
original discharge location. Per exemptions in the 1990 KCSWDM Core ,
Requirement# 3, detention and water quality controls are not required for this '�
project. ,
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1990 KC SWDM Core Requirements
Section 1.2.1 Core Requirement#1: Discharge at the Natural Location
• The site drains west, crossing the west property line as unconcentrated sheet
flow, draining west across a vacant lot covered with tall grass. As required by
this core requirement (the developed 100-yr SBUH peak runoffis 0.30 cfs),
the new roofs and driveway runoff will be discharged at the west property line
in a similar way, through a flow dispersion trench as shown in figure 4.3.6B
of the 1990 KCSWDM.
Section 1.2.2 Core Requirement #2: Offsite Analysis
• An offsite drainage analysis is provided in this report.
Section 1.2.3 Core Requirement#3: Runoff Control
• Because the increase in 100-yr peak flow for developed vs. existing conditions
is less than O.Scfs, detention is not required on this project. Because the new
impervious area subject to vehiculaz use is less than 5000 sq-ft, water quality
measures are not required.
Section 1.2.4 Core Requirement#4: Conveyance System
• The conveyance consists of a gutter for small flows from this sma11 project.
Therefore analysis is not needed..
Section 1.2.5 Core Requirement#5: Erosion/Sediment Control Plan
• A temporary erosion control plan provides BMP's to be implemented during
construction.
5ection 1.2.6 Core Requirement #6; Maintenance and Operation
• A maintenance and operations manual is provided in the TIR.
Section 1.2.7 Core Requirement#7: Bonds and Liability
• The developer will arrange for any financial guarantees and liabilities required
by the permit.
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tiING COUNTY, WASHINGTON, SURFACE W ATER DESIGN MANUAL
KING COUNTY,WASHINGTON
SURFACE WATER DESIGN MANUAL
APPENDIX A
MAINTENANCE REQUIREMENTS
FOR PRIVATELY MAINTAINED
DRAINAGE FACILITIES
Section No. Subject
1 Ponds
2 Infiltration
3 Closed Detention Systems
4 Control Structure/Flow Restrtctor
5 Catch Basins
6 Debris Barriers
7 Energy Dissapators
8 Fencing
9 Gates
10 Conveyance Systems
11 Grounds
12 Access Roads/Easements
1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
MAINTENANCE REQUIREMENTS FOR
PRIVATELY MAINTAINED DRAINAGE FACILITIES
NO. 1 - PONDS
Maintenance Conditions VYhen Maintenanc� Resuhs Expected When
Component Deisct b Nesded Msintenance Is Perfwmed
General Trash&Debris Any trash and dabrie which excead 1 cubic Trash and debris cleared from
foot per 1,000 square feet(this is about equal site.
to the emount of uash it would take to fill up
one stendard aize offica garbage can). In
general,there should be no visual evidence of
dumping.
Poisonous Any pasonous vepetation which may No denqer of poisonous
Vegetetion constitute a hezerd to County perso�nel or the vegetation where County
public. Examplea of poisonous vegetation pereonnel or the public miyht
include: tansy ragwort,poison oak, stinginy normally be. (Coordination with
nettles,devils club. Seattle/Kinp County Heaith
Department)
PoNution Oil,pasoline,or other contarrrnents of one No contaminants prese�t other
pallon or more or any smount found that than e surfece film. (Coordi�ation
could: 1)cause damape to plant, a�imal, or with Seattle/King County Heelth
marine life; 2)conatitute e fire hezerd; or Departmant)
3)be flushad downstream duriny rain atorms.
Urmowed Grass/ If facility is located in private resider�tisl aree, When mowinp is needed,
Ground Cover mowiny is needad when prass exceeds 18 prasslground cover should be
inches in heiyht. In other ereas,the paneral mowed to 2 inches in heiqht.
policy is to make the pond site match adjacent
. pround cover and tarrein as lonp as thera is no
interference with the function of the facility.
Rodent Holas Any evidence of rodent holes if fecility is Rodents destroyed end dam or
actinp as a dam or beRn, or any evidence of beRn repaired. (Coordination with
_ water pipinp throuph dem or berm via rodant Seattle/King County Health
holes. Deparunent)
Insecta Whan insects such as wasps and hornets Insecta destroyed or removed
interfere with maintenanca activities. from site. !
Tree Growth Trea growth does not ellow maintenance Treea do not hinder meintenance
access or intarfares with maintenance sctivity ectivitiea. Selectively cultivate
fi.e.,slope mowing, silt�emovd,vactoring, or trees such ea eldars for fi�ewood.
equipmant movements). If trees are not
interfering with eccess,leave vees alone.
Side Slopes of Erosion Erodad damape over 2 inches deep where Slopes should be etabilized by
Pond cause of damape is atill present or where using appropriate erosion control
there is potentiel for continuad erosion. meeaura(s);e.p., rock
reinforcament,plantinp of p�ass,
compecdon.
Storege Aree Sediment Accumuleted aediment that exceede 10%of Sediment cleaned out to deaiy�ed
the designed pond depth. pond ahape and depth;pond
reseeded if necessary to control
erosion.
Pond Dikes Sattlementa Any part of dika whicti has satdad 4 inches Oike should be built back to tha
lower than the design elevation. dasipn elevation.
, Emergency Rock N6ssine Only one layer of rock exists above nativa soil Replace rocks to design
Overflow/Spillway in are five square feet or larger,or eny standards.
exposure of native soil.
� A-1 11/94
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 2 - INFILTRATION
Meintsnance Co�ditlons Wh�n Meint�nana Results Expected Whon
Compone�t Detect b Needed Maintenenca Is Performed
General Trash&Debris See"Ponds" Stendard No. 1 See'Ponde"Standard No. 1
Poisonous See"Ponde" Stenderd No. 1 Sae"Ponde" Standard No. 1
Vagetation
Poilution See'Ponde"Stendard No. 1 See"Ponda"Stendard No. 1
Unmowed Grasa! See"Ponda"StandaM No. 1 Sae"Ponde"Standerd No. 1
Ground Cover
Rodent Holes See"Ponds" Ster►dard No. 1 See"Ponde"Stenderd No. 1
Insacta See"Ponds"Standard No. 1 See'Ponde"Stendard No. 1
• StoraAe Area Sediment A percolation test pit or test of facility Sedime�t is removed and/or
i�dicates facility is oniy workinp at 90%of its fecility is cleened ao that
designed capebilities. If two inches or more infilt�ation system works
• sedimant is prosent,removs. accordinq to desiyn.
Sheet Cover(If Sheet cover is visible and hes moro that tfuse Sheet cover repaired or replaced.
Applicable) 1/4inch holes in it.
Sump Filled with Any sediment and debris fillinp vault to 10% Cleen out oump to desipn depth.
Sedmiment end of depth f�om sump bottom to bottom of
Debris(If Applicable) outlet pipe or obetructing flow into tM
connector ppe.
Flter Bags Filled with Sediment and debris fill bae more than 1/2 Replace fiher bap or redesiyn
Sedmiment end full. system. '
Debris ,
Rock Flters Sediment and Debria By visual inspection,little or no water flows Replace pravel in rock fllter.
through filter during heavy rain stortna.
Side Slopes of Erosion See'Ponde"Standard No. 1 Sea"Ponde"$tandard No. 1
Pond
Emerge�cy Rock Missing See'Ponda"Standard No. 1
Overflow Spillway
Settlinq Ponds and Sediment Remove when 6" or more.
Vaulta
Note: Sediment accumulation of more than .25 inches per year may i�dicate excessiva erosion ie occurring upstreem of the facility or
that conveyance systems ere not being p�ope�ly meintsinad. The contributing dreinaye erea should ba chpcked for erosion problems •
or inedequate maintananca of conveyence systems if excessive sedimentation ia noted in an i�filtration facility.
Chedc twice a year during first 2 years of ope�ation; once a year thereafter. Gaen manholeslcatch basins, repair damaged
ir�lets/oudets, clean trash recks.
� A_2 11/94
KING COUNTY, WASHINGTON, S.URFACE WATER DESIGN MANUAL
NO. 3 - CLOSED DETENTION SYSTEMS (PIPES/TANKS)
Maintenanee Conditions When Malntenance ResuFts Expected
Component Defect is Needed When Malntenance is Performed
Storage Area Plugged Air Vents One-haM of the cross section of a vent is Vents free of debris and sediment.
blocked at any point with debris and
sediment.
Debris and Aacumulated sediment depth exceeds Ali sediment and debris removed from
Sediment 10%oi the diameter of the storage area storage area.
for 1/2 length oi storage vault or any
point depth exceeds 15%of diameter.
Example: 72-inch storage tank would �
require cleaning when sediment reaches
depth of 7 inches tor more than 1/2
length of tank.
�
Joints Between My crack allowing material to be AJI joints between tank/pipe sections are II
Tank/Pipe Section transported into facility. sealed.
Tank/Pipe Bent My part of tank/piPe is bent out of shape Tank/pipe repaired or replaced to design. '
Out of Shape more than 1096 of its design shape. I
Manhole Cover not in Place Cover is missing or oniy partially in place. Manhole is dosed. '
� My open manhole requires maintenance.
Locking Mechanism cannot be opened by one Mechanism opens with proper tools. I,
Mechanism Not maintenance person with proper tools.
Working Bolts into frame have less than 1/2 inch •
of thread (may not appiy to self-locking ,
lids). '
Cover Difficult to One mai�tenance person cannot remove Cover can be removed and reinstalled by
Remove � lid after applying 80 pounds of lift. Intent one maintenance person.
is to keep cover from sealing off access
to maintenance.
Ladder Rungs IGng County Safety Office and/or L.adder meets design standards and
Unsafe maintenance person judges that ladder is allows mai�tenance persons safe access.
unsafe due to missing rungs,
misalignment,rust,or cracks.
Catch Basins See"Catch Basins'Standard No.5 See'Catch Basins'Standard No.5
A-3 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 4 - CONTROL STRUCTURE/FLOW RESTRICTOR
Maintenance Conditlons When Malntenance Results Exp�cted
Component Defect is Needed When Malntenance Is Pertormed
General Trash and Debris Distance between debris build-up and All trash and debris removed.
(Includes bottom of orifice piate is less than 1-1/2
Sediment) feet.
Structural Damage Structure is not securely attached to Structure securely attached to wall and
manhole wall and outlet pipe structure outlet pipe.
should support at least 1,000 pounds of
up or down pressure.
Structure is not in upright position (allow $tructure in correct position.
up to 10%trom plumb).
Connections to outl�t pipe ere not Connections to ouGet pipe are watertight;
watertight and show signs ot rust. � structure repalred or replaced and works
as designed.
My holes—other than designed holes— Structure has no holes other than
. in the structure. designed holes.
Cleanout Gate Damaged or Cieanout gate is not watertight or is Gate is watertight and wor{cs as designed.
Missing missing.
Gate can�ot be moved up and down by Gate moves up and down easily and is '
one maintenanoe person. watertight
Chain leading to gate is missing or Chain is in place and works as designed. ,
damaged.
Gate is rusted over 50%of its wrface Gata is repaired or replaced to meet
_ area. design standards.
Orifice Plate Damaged or Control devioe is not workinp property Plate is in place end works as designad.
Missing due to missing,out of place,o�bent
orifice plate.
Obstructions Any trash,debris,se�liment,or vegetatio� Plate is free of all obetructions and works
blxking the plate. as designed.
Overflow Pipe Obstructions My trash or debris blodcing (or having Pips is free of nll obstructions euid works
the potential ot blocking)the overflow as designed.
P�Pe•
Manhole See`Closed Detention Systems'Standard See'qosed Detention Systems"Standard
No.3. No.3.
Catch Basin See'Catch Basins"Standard No.5. See'Catch Basins"Standard No.5.
A-4 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 5 - CATCH BASINS
Maintenance CondiUons When Maintenancs Resuks Expected II
Component Detect is Needed When Malntenance is Pertormed
General Trash&Debris Trash or debris of more than 1/2 cubic No trash or debris located immediately in I
(Includes foot which is located immediately in front iront of catch basin opening.
Sediment) of the catch basin opening or is blocking I
capacity of basin by more than 10%.
Trash or debris (in the basin)that No Vash or debris in the catch basin.
exceeds 1/3 the depth irom the bottom
of basin to invert of the lowest pipe into
or out of the basin.
Trash or debris'in any inlet or outiet pipe Inlet and outlet pipes free of trash or
blocking more than 1/3 of its height. debris.
Dead animals or vegetatio�that could No dead animals or vegetation present
generate odors that would cause within the catch basin.
complaints or dangerous gases (e.g.,
methane).
Deposits of garbage exceedirtg 1 cubic No condition present which would attract
foot in volume. or support the breeding of insects or
rodents.
Struetural Damage Corner of frame extends more than 3/4 Frame is even with curb.
to Frame and/or inch past curb face into the street (if �
Top Slab applicable).
Top slab has holes larger than 2 square Top slab is free of holes and cracks.
inches or cracks wider than 1/4 inch
(ntent is to make sure all material is
running into the basin). '
Frame not sitting flush on top slab,(.e., Frame is sitting flush on top slab.
separation of more than 3/4 inch of tha
irame from the top siab.
Cradcs in Basin Cracks wlder than 1/2 inch and bnger Basin replaced or repaired to design
Walis/Bottom than 3 feet,any evidence of soil particles standards.
entering catch basin through aacks,or
maintenance person judges that structure
is unsound.
Gacks wider than 1/2 inch and bnger No cracks more than 1/4 inch wide at the
than 1 foot at the joint of any inlet/outlet joiM oi inlet/outlet pipe.
pipe or any evidence of soil particles
entering catch basin through cxadcs.
Settlement/ Basin has settled more than 1 inch or has Basin replaced or repaired to design
Misalignment rotated more than 2 inches out of standards.
alignment.
Fre Haza�d Presence of chemicals such as natural No flammable chemicals present.
gas,oil,and gasoline.
Vegetation Vegetation growing across and blocking No vegetation blxking opening to basin.
more than 10%01 the basin opening.
Vegetation growing in inlet/ouUet pipe No vegetation or root growth present.
joints that is more than six inches tall and
less than six inches apart.
Pollution Nonflammable chemicals of more than No pollution present other than surface
1/2 cubic foot per three feet of basin film.
length.
A-5 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 5 - CATCH BASINS (Continued)
Maintenance Condtdons When Maintenance Re�uRs Expected
Component Defect Is Needed When Maintenance Is Psrtormed
Catch Basin Cover Cover Not in Place Cover is missing or only partially in place. Catch basin covar is dosed.
My open catch basi� requires
maintanance.
Locking Mechanism cannot be opened by one Mechanism opens with proper tools.
Mechanism Not maintenance peraon with proper tools,
Working BoRs into frame have less than 1/2 inch
of thread.
Cover Di�cult to One maintenance person ca�not remove Cover can be removed by one
Remove lid after applying 80 Ibs.of lift; intent is maintenance person.
keep cover from sealing off axess to
maintenance.
Ladder Ladder Rungs Ladder is unsate due to missing rungs, Ladder meets design standards and
Unsafe misalignment,rust,cracks,or sharp allows maintenance person safe access.
edges.
Metal Grates Grate with opening wider than 7/8 inch. Grate openings meet des(gn standards.
(if applicable)
Trash and Debris Trash and debris that is blocking moro Grate free oi Vash and debris.
than 20%of grate surface.
Damaged or Grate missi�g or broken member(s)of Grate is(n place and meets desi :
Missing the grate. standards.
A-6 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 6 - DEBRIS BARRIERS (e.g. Trash Racks)
Maintenance Conditlons When Malntenancs Resulta Expected
Component Defect is Needed 1Nhen Maintenance Is Performed
General Trash and Debris Trash or debris that is plugging more Barrier Gear to receive capacity flow.
than 2096 of the openings in the barrier.
Metal Damaged/Missing Bars are bent out of shape more than 3 Bars in place with no bends more than
Bars inches. 3/4 inch.
Bars are missing or entire barrier is Bars in place according to design.
missing.
Bars are loose and rust is causing 50% Repair or replace barrier to design
deterioration to any part of barrier. standards.
A-7 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 7 - ENERGY DISSIPATORS
Maintenance Condittons Whan Malntenance Resuks Expectod
Component Detect Is Needed When Malntenance Is Periormed
External:
Rock Pad Missing or Moved Only one layer of rock exists above native Replace rocks to design standard.
Rock soil in area five square feet or larger,or
any exposure of native soil.
Dispersion Trench Pipe Plugged with Accumulated sediment that exceeds 20% Pipe deaned/ilushed so that it matches
Sediment of the design depth. dasign.
Not Discharging usual evidence of water discharging at Trench must be redesigned or rebuilt to
Water Properly concentrated points along trench (normal standard.
condiGon is a"sheet flow'of water along
trench). Intent is to prevent erosion
damage.
Perforations Over 1/2 ot perforations in pipe are Clean or replace perforated pipe.
Pfugged plugged with debris and sediment.
Water Flows Out Maintenance person observes water Facility must be rebuilt or redesigned to
Top of"Distributor" Nowing out during any storm less than standards: I
Catch Basin the design storm or k is causing or
appears likely to cause damage.
Receiving Area Water in receiving area is causing w has No danger of landslides. I'
Ooer-Saturated potential of causing landslide problems.
Internal: �
Manhole/Chamber Wom or Damaged SVucture dissipaGng flow deteriwates to Raplace structure to design standards.
Posts, Baffles, 1/2 or original size or any concentrated
Sides oi Chamber worn spot exceeding one square foot
which would make structure unsound.
Other Defects See"Catch Basins'Standard No.5 See"Catch Basins"Standard No.5
A_8 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 8 - FENCING
Maintenance CondiUons When Malntenance Reautts Expected
Component Detect is Needed YVhen Maintonance Is Periormed
General Missing or&oken Any defect in the fence that permits easy Parts in place to provide adequate
Parts entry to a facility. security.
Parts broken or missing. &oken or missing parts replaced.
EroSion Erosion more than 4 inches high and 12- No opening under the tence that exceeds
18 inches wide permitting an opening 4 inches in height.
under a fence.
Wire Fences Damaged Parts Posts out of plumb more than 6 inches. Posts plumb to within 1-1/2 inches.
Top rails bent more than 6 inches. Top rail free of bends greater than 1 inch.
Any part of fence (ncluding posts,top Fenoe is aligned and meets design
rails,and tabric)more than 1 ioot out of standards.
design alignment.
Missing or loose tension wire. Tension wire in place and holding iabric.
Missing or loose barbed wire that is Barbed wire in piace with less than 3/4-
sagging more than 2-1/2 inches between inch sag between posts. '�
posts, ',
Extension arm missing,broken,or bent Extension arm in place with no bends '
out of shape more than 1-1/2 inches. larger than 3/4 inch. I
Deteriorated Paint Part or parts that haye a nisting or scaling Structurally adequate posts or parts with j
or Protective condition that has affected structural a uniform protective coating.
Coating adequacy.
Openings in Fabric Openings in fabric are such that an& No openings in fabric.
inch-diameter ball could fit through.
A-9 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 9 - GATES
Malntenance CondiUons When Malntenaoce Results Expscted
Component Detect Is Needed When Maintonance Is Periormed
General Damaged o� Missing gate or locking devices. Gates and lodcing devices in place.
Missing Members
. &oken or missing hinges such that gate Ffinges intact and lubed. Gate is working
cannot be easily opened and closed by a freely.
maintenance person.
Gate is out of plumb more than 6 inches Gate is aligned and vertical.
and more than 1 foot out of design
alignment.
Missing stretcher bar,stretcher bands, Stretcher bar,bands,and ties in piace.
• and ties.
Openings in Fabric See'Fencing"Standard No.8 See'Fencing'Standard No.8
i
I
A-10 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
. NO. 10 - CONVEYANCE SYSTEMS (Pipes & Ditches)
Mainienance Conditions When Maintenance Resufts Expected
Component De(ect is Noeded When Maintenance fs Periormed
Pipes Sediment 8�Debris Accumulated sediment that exceeds 20% Pipe cleaned of all sediment and debris.
of the diameter of the pipe.
Vegetation Vegetation that reduces free movement of All vegetation removed so water flows
water through pipes. freely through pipes.
Damaged Protective coating is damaged; rust is P'ipe repaired or replaced.
causing more than 50%deterioration to
any part of pipe.
My deM that decreases the cross section Pipe repaired or replaced.
area of pipe by more than 20%.
Open Ditches Trash 8�Debris Trash and debris exceeds 1 cubic foot Trash and debris cleared from ditches. �
per 1,000 square feet of ditch and slopes.
Sediment Axumulated sediment that exceeds 2096 Ditch cleaned/flushed of all sediment and
of the design depth. debris so that it matches design. �
Vegetation Vegetation that reducas free movement oi Water flows freely through ditches.
water through ditches.
� Erosion Damage to See'Ponds'Standard No. 1 See'Ponds'Standard No. 1
Slopes
Rock Lining Out ot Maintenance person can see native soil Replace rocks to design standard.
Place or Missing (H beneath the rock lining.
Applicable)
Catch Basins See'Catch Basins'Standard No:5 See'Catch Basins'Standard No.5
Debris Barriers See'Debris Barriers`Standard No.6 See"Debris Barriers'Standard No.6
(e,g.,Trash Rack)
A-11 1/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 11 - GROUNDS (Landscaping)
Maintenance Cor►dWons When Maintenance Resuks bcpseted
Component Defect la Needed Wh�n Maintenance Is P�rformed
General Weeds Weeds growing in mora than 2096 of the Weeds present i�less than 596 of the
(Nonpoisonous) landscaped area (trees and shrubs only). la�dscaped area.
Safety Hazard My presence of poison ivy or other No poisonous vegetation present in a
poisonous vegetation. landscaped area.
Trash or Litter Paper,can,bottles,totalling more than 1 Aren dear of Iftter.
cubfc toot within a landscaped area(trees
and ahrubs only)of 1,000 square teet.
Trees and Shrubs Damage Umbs w parts of trees or shrubs that are Trees and shrubs with less than 5%of the
split or broken which aHect more than total foliage with split or broken limbs.
2546 of the total foliage of the tree or
ahrub.
Trees or shn�bs that have been blown Troe or ahrub in plaoe free of Injury.
• down or knxked over.
Trees or ahrubs which are not adequately Tree or ahrub f�plaoe and adequately
supported or are leaning over,causing supportad;remove eny dead or diseased
exposure of the roots. trees,
A-12 1�
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
NO. 12 - ACCESS ROADS/EASEMENTS
Maintenance Conditions When Maintenance Resuks Expected
Component Detect Is Needed When Maintenance Is Periormed
General Trash and Debris Trash and debris exceeds 1 cubic foot Trash and debris deared from site.
per 1,000 square feet,i.e.,trash and
debris would fill up one standard size
garbage can.
Blocked Roadway Debris which could damage vehicle tires Roadway free of debris which could
(glass or metai). damage tires.
Any obstructions which reduce dearance Roadway overhead dear to 14 feet high.
above road surface to less than 14 teet.
My obsWctions restricting the axess to Obstruction removed to allow at least a
a 10-to 12-foot width for a distance of 12-foot access.
mora than 12 feet or any point restricting
access to less than a 10-foot width.
Road Surface Settlement, 1Nhen any surface defect exceeds 6 Road surface uniformly smooth with no
Pothotes, Mush inches in depth and 6 square feet in area. evidence oi settlement,potholes,mush
Spots, Ruts In general,any surface defect which spots,or ruts.
• hinders or prevents maintenance access. '
Vegetation in Road Weeds growing in the road surface that Road surface free of weeds taller than 2
Suriaoe are more than 6 inches tall and less than inches.
6 inches apart within a 400-square-foot
area.
Shoulders and Erosion Damage Erosion within 1 toot of the roadway more Shoulder free of erosion and matching
Ditches than 8 inches wide and 6 inches deep. the surrounding road.
Weeds and &ush Weeds and brush exceed 18 inches in Weeds and brush cut to 2 inches in
height or hinder maintenance aocess. height or cleared in such a way as to
allow maintenance access.
� .
A-13 1�