HomeMy WebLinkAboutStorm Drainage Report Final - PLN General - 8/21/1998 r ,
FINAL STORM DRAINAGE REPORT FOR J Bar D MINI-STORAGE
LOCATED IN BELFAIR,WASHINGTON
AUGUST 21,1998
FOR:
J Bar D
18490 Hwy 305
Poulsbo,WA 98370
731-9091
PREPARED BY:
Team 4 Engineering
Suite A, Box 2
5823 NE Minder Road
Poulsbo, WA. 98370
(360)297-5560
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18649
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EXPIRES 1/30
TABLE OF CONTENTS
L LOCATION PG.3
IL PREDEVELOPMENT SITE CONDITIONS PG.3
IIL UPSTREAM ANALYSIS PG.4
IV. DOWNSTREAM ANALYSIS PG.4
V. DESCRIPTION OF PROPOSED DEVELOPMENT PG.4
VL OVERVIEW OF PROPOSED STORMWATER MANAGEMENT FACILITIES PG.4
VIL TECHNICAL REQUIREMENTS PG.5
VEIL HYDROLOGICAL ANALYSIS PG.S
IX. STORMWATER QUALITY ENHANCEMENT FACILITIES PG.9
X. EROSION AND SEDIMENT CONTROL PG.9
FIGURES
FIGURE 1 VICINITY MAP PG. 10
FIGURE 2 PREDEVELOPED SITE MAP PG. 11
FIGURE 3 SOILS MAP PG. 12
FIGURE 4 DEVELOPED CONDITIONS SITE MAP PG. 13
EXHIBITS
EXHIBIT 1 HYDROLOGIC SOIL GROUPS PG. 14
EXHIBIT 2 CURVE NUMBERS PG. 15
EXHIBIT 3 MANNING'S COEFFICIENTS PG. 16
EXHIBIT 4 100 YR,24 HR ISOPLUVIAL PG. 17
ATTACHMENTS
ATTACHMENT 1 BIOSWALE DESIGN PG. 18
L LOCATION
The proposed development is located on a 5.34 acre parcel, in the Northwest quarter of
the Northwest quarter of Section 32 Township 23 North,Range 1 West, W.M., in Mason
County, Washington. The site is situate in Belfair and is immediately east of Navy Yard
Highway. The Assessor's Parcel Number for the site is 123325000020.
Adjacent projects include the Belfair Baptist Church to the north, and the Belfair Doctoes
Clinic to the south.
IL PRE-DEVELOPMENT SITE CONDITIONS
The site is approximately 5.34 acres and contains three drainage basins. The area to be
developed is labeled basin A-preTOT. The two remaining basins consist of native
vegetation and are the remnants of a logged off area. Both remaining drainage basins are
located on the upper undeveloped portion of the property and discharge storm waters to
the north and south away from the project site. Their respective areas are not used in the
calculations. See Figure 2 —Pre-Development Site Map.
The DOE Manual assumes the conditions of the site in 1988 were established second
growth forest. For the purposes of this analysis, this pre-grading site condition of
established second growth forest has been used.
The soils on site are listed in the"Soil Survey of Mason County Area, Washington"
prepared by the United States Department of Agriculture, Soil Conservation Service as
Everett gravelly sandy loam, 15 to 30 percent slopes. See Figure 3 — Soils Map. The
Everett soil group is listed as Hydrologic Group A in Table III-1.6 of the DOE
Stormwater Manual—Hydrologic Soil Group in the Puget Sound Basin. Soil logs
excavated on the site for this project show data consistent with the SCS mapping.
III. UPSTREAM ANALYSIS a
There are no basins upstream of this proposed project to analyze therefore there is no
analysis used in the following calculations.
IV. DOWNSTREAM ANALYSIS
All runoff from the JBarD Mini-Storage project flows west to the infiltration ditches
located on the west side of the project, adjacent to the Navy Yard Highway. The roofs
will also be infiltrated in trenches located in between each set of buildings.
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V. DESCRIPTION OF PROPOSED DEVELOPEMT
The developed site contains three drainage basins. The developed area is labeled basin A-
dev-INFIL. The remaining drainage basins are located in the upper portion of the project
and drain the north and south into the adjoining second growth forest next to the
development area. See Figure 4—Developed Conditions Site Map.
The site is owned by Jesse Wallace et al and is located in the UGA of Belfair. The owner
proposes to initially build five metal buildings of the following sizes; 3 @ 3,500 S.F. and
2 @ 4,750 S.F. with asphalt parking and drive aisles. The project will be phased into 2
initial phases.
Water for domestic use and fire flow will be service from Belfair Water District. An
eight-inch main is located on the west of the Navy Yard Highway and an 8" line will
brought under the highway via a boring. Sanitary will be on-site disposal. The primary
and reserve drainfields for all buildings will be located to the south and east of proposed
building A5.
VI. OVERVIEW OF PROPOSED STORM WATER MANAGEMENT
FACILITIES
The portion of the site, which will be developed, is Everett series with long term high
infiltration capacity (hydrologic soil group A). Seven soil logs have been excavated
which confirm the high infiltration capacity of the in-situ soils. Therefore the selected
method of Stormwater Management for the project is Infiltration.
The building roofs will discharge to individual infiltration trenches. Each set of buildings
will be equipped with one trench for each half of the roof. The trenches have been sized
using Waterworks software version 6.1.2.5b in conjunction with the DOE manual.
The paved and landscaped areas will be graded for surface flow and storm drain flow
discharging to a bioswale. The bioswale is designed to provide Quality enhancement for
the 6 month, 24 hour storm event. The bioswale will discharge to a Spill Containment
Oil/Water separator to an underground infiltration trench. These facilities will provide
infiltration of runoff for the 100 yr., 24 hr. storm for all paved and most of the landscaped
areas on the developed site.
Storm waters from two areas will not be detained on site. The first is the 7.5 foot wide
landscaping strip located on the north side of the project. The second area is
approximately 0.16 acres in size and is located at the west end of the project between the
Navy Yard Highway and the west edge of the parking lot at Building A l. These storm
waters will discharge directly into the state ditch and flow both north and south away
from the site.Bypass areas such as these two areas have relatively small cfs discharges
4
and are not included in the calculations. There will be a net reduction of runoff entering
the state highway roadside ditch as a result of project development.
VII. TECHNICAL REQUIREMENTS
The DOE Stormwater Management Manual defines technical requirements.
• The Water Quantity Mitigation facilities will be infiltration trenches
designed to retain the 100 year, 24 hour, type 1 A storm.
• The Water Quality Mitigation facilities will be a bioswale designed to
provide treatment for the 6 month, 24 hour storm event. This design event
is equivalent to 64%of the 2 year, 24 hour,type 1 A storm for the
developed condition.
VM- HYDROLOGIC ANALYSIS
Runoff computations utilize the SCS-based hydrograph method, Santa Barbara Urban
Hydrograph (SBUH) method with Type I A rainfall distribution.
The hydrological analysis was performed using WaterW
. P g orksHMS (Release 6.1.2.Sb b
Y
Engenious Systems, Inc.
Other parameters are as follows:
• Runoff Curve Numbers (CN), Type I Storm; See Exhibit 2 - Table 5-2
Modified Curve Numbers.
• Manning Coefficients; See Exhibit 3 - Table 5-3 Manning
Coefficients/"K" Factors.
• 100 year, 24 hour Precipitation Isopluvial- See Exhibit 4.
1. ROOF AREAS
The roof runoff from the buildings will be infiltrated in infiltration trenches constructed
using washed rock for drainfields. The length of trench required was computed using
software as mentioned above.
The footprint of buildings Al & A5 are 3,500 S.F. (0.0803 ac.) with a ridgeline dividing
the roof area in half. Using sand at 4.14 min./in. a 1/2 roof area of 1,750 s. f. for half of
the roof, and a 3' deep trench; the design dictates 168 s. f. of trench bottom area is
required. With a 4.2' wide trench, the trench will be 40 feet long for the north half of the
building.
The footprint of a typical two building configuration (B1dgs.A2, A3&A4) is 8,250 S.F.
(0.1894 ac.) with a ridgeline dividing each roof area in half. Using sand at 4.14 min./in., a
1/2 roof area of 1,750 s. f. for the smaller of the two buildings and a 1/2 roof area of
5
2,375 s.f..for the larger building, and a 3' deep trench; the design dictates 400 s. f. of
trench bottom area is required. With a 10' wide trench, the trench will be 40 feet long.
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2. 100 yr, 24 HOUR STORM
Drainage Area: ApreTOTAL
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur 24.00 hrs
Area CN TC
Pervious 2.3100 ac 55.00 0.58 hrs
Impervious 0.0000 ac 0.00 0.00 hrs
Total 2.3100 ac
Supporting Data:
Pervious CN Data:
PHASE 1/2 & BASIN B 55.00 2.3100 ac
Pervious TC Data:
Flow type: Description: Length: Slope:
Coeff: Travel Time
Sheet 2ND GROWTH FOREST 159.00 ft 15.71% 0.4000 13.05 min
Sheet 2ND GROWTH FOREST 133.00 ft 15.02% 0.4000 11.52 min
Shallow 2ND GROWTH FOREST 139.00 ft 14.35% 3.0000 2.04 min
Shallow 2ND GROWTH FOREST 234.00 ft 19.23% 3.0000 2.96 min
Shallow 2ND GROWTH FOREST 270.00 ft 8.88% 3.0000 5.03 min
2 yr Flow Time Volume
Summary: 3.0345 cfs 12.17 hrs 14630.57 cf- 0.3359 acft
Drainage Area: Adev-INFIL
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur 24.00 hrs
Area CN TC
Pervious 0.8700 ac 56.05 0.43 hrs
Impervious 0.7400 ac 98.00 0.05 hrs
Total 1.6100 ac
Supporting Data:
Pervious CN Data:
BASIN B 55.00 0.8000 ac
LANDSCAPING 68.00 0.0700 ac
Impervious CN Data:
ata:
ASPHALT DRIVE AISLES 98.00 0.7400 ac
Pervious TC Data:
Flow type: Description: Length: Slope:
Coeff: Travel Time
Sheet 2ND GROWTH FOREST 300.00 ft 15.03% 0.4000 22.07 min
Shallow 2ND GROWTH FOREST 131.00 ft 15.03% 3.0000 1.88 min
Channel 12" N-12 465.00 ft 10.25% 42.0000 0.58 min
Shallow BIOSWALE 70.00 ft 1.00% 11.0000 1.06 min
imPervious TC Data:
Time of Concentration: 2.73 min
2 yr Flow Time Volume
Summary: 3.0345 cfs 12.17 hrs 14630.57 cf- 0.3359 acft
Drainage Area: Typ.2-bldg.Roof
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur 24.00 hrs
Area CN TC
Pervious 0.0000 ac 0.00 0.00 hrs
Impervious 0.0947 ac 98.00 0.01 hrs
Total 0.0947 ac
Supporting Data:
Impervious CN Data:
Typical 2-Bldg.1/2 roof 98.00 0.0947 ac
imPervious TC Data:
Time of Concentration: 0.65 min
2 yr Flow Time Volume
Summary: 3.0345 cfs 12.17 hrs 14630.57 cf- 0.3359 acft
Drainage Area: pre-typ.2-bldg.roof
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur 24.00 hrs
Area CN TC
Pervious 0.2571 ac 55.00 0.17 hrs
Impervious 0.0000 ac 0.00 0.00 hrs
Total 0.2571 ac
Supporting Data:
Pervious CN Data:
2nd growth forest 55.00 0.2571 ac
Pervious TC Data:
Flow type: Description: Length: Slope:
Coeff: Travel Time
Sheet 2nd growth forest 120.00 ft 16.00% 0.4000 10.34 min
2 yr Flow Time Volume
Summary: 3.0345 cfs 12.17 hrs 14630.57 cf- 0.3359 acft
7
.The following data from the History File of Waterworks for this project presents the
parameters and results of the analysis:
Project Precipitation
[2 yr] 3.50 in
[5 yr] 0.00 in
[10 yr] 5.00 in
[25 yr] 0.00 in
[100 yr] 7.00 in
BasinlD Peak Q Peak T Peak Vol Area Method Raintype
Event
(cfs) (hrs) (ac-ft) ac /Loss
ApreTOTAL 0.50 8.50 0.4088 2.31 SBUH/SCS TYPEIA 100yr
Adev-INFIL 1.41 7.83 0.5782 1.61 SBUH/SCS TYPE1A 100 yr
pre-typ.-2-bldg. 0.08 8.00 0.0455 0.26 SBUH/SCS TYPEIA 100 yr
roof
Typ.2-bldg.roof 0.16 7.83 0.0534 0.09 SBUH/SCS TYPEIA 100 yr
Node ID: infil trench
Desc: infiltration trench-1 00'x39'
Start El: 115.150 ft Max El- 118.150 ft
Contrb Basin: Contrib Hyd:
Length Width Void Ratio
100.0000 ft 39.0000 ft 30.00
Node ID: ROOF TRENCH 1 (typ. Of 4)
Desc: infiltration trench-40'x10'
Start El: 151.5000 ft Max El.- 154.5000 ft
Contrib Basin: Contrib Hyd:
Length Width Void Ratio
40.0000 ft 10.0000 ft 30.00
R
f
Descrip: Staged Discharge
Start El Max El Increment
115.150 ft 118.150 ft 0.10
Stage Discharge
115.150 ft 0.0000 cfs
115.160 ft 0.3737 cfs
118.150 ft 0.3738 cfs
Control Structure ID: INFILROOF 1 - Stage Discharge rating curve
Descrip: Staged Discharge
Start El Max El Increment
151.5000 ft 154.5000 ft 0.10
Stage Discharge
151.5000 ft 0.0000 cfs
151.5100 ft 0.0382 cfs
154.5000 ft 0.0383 cfs
IX STORMWATER QUALITY ENHANCEMENT FACILITIES
The Stormwater quality enhancement will be provided by a bioswale sized to treat the 6
month storm. The 6 month storm runoff rate from Basin A-devINFIL is calculated as
64% of the two year storm runoff rate. The two year storm peak discharge as calculated
by Waterworks is as follows;
2 yr Flow Time Volume 6 Month
Summary: 0.6253 cfs 7.83 hrs 9982.16 cf- 0.2292 acft 0.4008 cfs
X. EROSION AND SEDIMENT CONTROL
The site is small in acreage, with moderate ground slopes and combined with the fact that
the soils are sandy, the potential for erosion and sedimentation problems is low. Erosion
and sedimentation control measures will be installed as the first work on the site. The
TESCP includes the following elements;
• Filter Fabric Fence along the north & west boundary.
• Stabilized construction entrance.
• Installation of a Sedimentation Trap. (20'x 10')
0 Installation of Interception ditch with straw bale dams along a portion of
the north property line.
At this point the TESCP changes to a Maintenance Program. Elements of the
maintenance program extend beyond maintenance of the above described facilities to
application of best management practices to include slope stabilization, covering exposed
areas, and other measures as included in the project notes, "Minimum Erosion and
Sedimentation Control Requirements" and "General Erosion and Sedimentation Control
Requirements".
9
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STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN
Table M-1.6 Hydrologic Soil Groups foe Soils in the Puget Sound Basin
tc
Hydrologic Soil H drolo
Soil Type Group Soil Type
y g Soil
Group
Agnew C Colter Ail B Custer C
C
C
ND
Alderwood C Dabob ND
Delphi
Arena. Alderwood B Dick D
Aa Ahw, Everon B Dimal ND
ldhiu B p
Ba Dupont D
Barnenoo Barimostt C
Baumgard B Eld�wtck C
Beauaite B Elwell B
Belfast C Eaquatzel B
Bellingham D Everett
Bellingham variant C A
Everson
Boistfon B Galvin
Bow A D
D Getchell
Briseot BuckleyD Giles
Bucher
C Godfrey D
B Grnenwaar A
Cagey C
Cariaborg Grove C
ND Harsune C
Caney ND Hartnit
Caaaolary ND
Cathcart C Hoh ND
Centralia B Hoko ND
ChesaChehalis
B Hoo dal rt CD
Cinebar B Hu�us ND
Clallam ND
Clayton C Indianola ND
B Jonas
Cwetal beach" variable B
Kapowa° CID Jun" ND
Katula Kalalocb C
Kilchis C RA°tO° D
Kitaap Republic B
Klaus
C Riverwash variable
KlonND Rober
Later ND Salal C
Lana C C
Lebam Salkum B
Lummi B Sammarrush D
ND
Lynnwood San JuanND ND
L stair Scamman D
y ND Schneider
Mal g
Manley
C Seattle D
Mashel B Sekiu
Maytown B Serruahmoo DD
McKenna C Shalcar D
D Shano B
McMurray ND Shelton Melbourne ND C
Menzel B Si CND
Sinclair C
Mixed Alluvial variable Skipopa
Molaon B D
Mukilteo CID Skykonush B
Neff Sruhopish ND
Natgar
B SnohorruM D
National
A Solduc B
s
Neilson a�ND Sollek ND
A S
p D
III-1-9 FEHRUARY, 1
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Table 5-3 MANNING'S COEFFICIENTS/"K"
O.
"n" AND "k" Values Used in Time Calculations for Hydrographs
"ns" Sheet Flow Equation Manning's Values (for the initial 300 ft. of travel) ns
Smooth surfaces (concrete, asphalt, gravel, or bare hand packed soil) 0.011
Fallow fields or loose soil surface (no residue) 0.05
Cultivated soil with residue cover (ss 0.20 ft/ft) 0.06
Cultivated soil with residue cover (s > 0.20 ft/ft) 0.17
Short prairie grass and lawns 0.15
Dense grasses 0.24
Bermuda grass 0.41
Range (natural) 0.13
Woods or forest with light underbrush 0.40
Woods or forest with dense underbrush 0.80
*Manning values for sheet flow only, from Overton and Meadows 1976 (See TR-55, 1986)
"k" Values Used in Travel Time/Time of Concentration Calculations
Shallow Concentrated Flow (After the initial 300 ft. of sheet flow, R = 0.1) kS
1. Forest with heavy ground litter and meadows (n = 0.10) 3
2. Brushy ground with some trees (n = 0.060) 5
3. Fallow or minimum tillage cultivation (n = 0.040) g
4. High grass (n = 0.035) 9
5. Short grass, pasture, and lawns (n = 0.030) 11
6. Nearly bare ground (n = 0.025) 13
7. Paved and gravel areas (n = 0.012) 27
"Channel flow (intermittent) (At beginning of visible channels R = 0.2) kc
I. Forested swale with heavy ground litter (n = 0.10) 5
2. Forested drainage course/ravine with defined channel bed (n = 0.050) 10
3. Rock-lined waterway (n = 0.035) 15
4. Grassed waterway (n = 0.030) 17
5. Earth-lined waterway (n = 0.025) 20
6. CMP pipe (n= 0.024) 21
7. Concrete pipe (0.012) 42
8. Other waterways and pipe 0.508/n
Channel Flow (Continuous stream, R = 0.4) k
9. Meandering stream with some pools (n = 0.040) 20
10. Rock-lined stream (n = 0.035) 23
11. Grass-lined stream (n = 0.030) 27
12. Other streams, man-made channels and pipe 0.807/n**
**See Table 7-3 for additional Mannings "n" values for open channels.
EXHIBIT 3 - MANNING'S COEFFICIENTS
STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN
49 124 123 122 121
45
7 y EL
6
00 A .
/S 1 40
1� 111I 1 ( 1p 55 14�
\ �Fi[Gr MAREiOp -PORT SlAt \ dl C
S t
•E� ot5 30 l '
\�75
21 I
9
481 � I 3 b2
I
� 7
t0
t o
so
10090 40
t0
i ts. - ' 1 I l 40 1 rc
P I
01 1 s
60. 00
47 1�— 3 35�
• ABE E
p 70 5 / E 1R L Y 0 ri
j16
60\I1I 2
100 61 ri 12 YAK
601 15 55
to
0 7
6s
55 � 65 7e T I t0
65 �60 SS w 10 AD�mc �25.
46 SU� 6
WASHINGTON 40 10 CKLI
10 0 10 20 30 40 6ttDEN E
MILES /0( L MU
66ru35
—
flgUr!$0 NOAA ATLAS 2, Volume IX
/S so 55 65 Preoeretl oy U.S.Deoermwent of ca6meres
ISOPLUVIALS OF 100•YR 24•HR PRECIPITATION
IN TENTHS OF AN INCH Notional weather
Atm000henc I Hydrology
Notional WeetNer Service,Oti'co O1�Iiytlr0logy
fheooretl for US.Woortnsent of A`I N:ufture,
SON C-ons"'"t—Service,Enpneering Division
124 12J 122
121
III-1-46 FEBRUARY, 1992
� L31 . 11
BIOSWALE DESIGN WORKSHEET
Project Name
JBarD mini-storage Job No. 00005
By: MAK
Client Jesse Wallace Date: 8/25/98
Q=(1.486/n)"A"R^2/3"S^1/2
where: Q= Flow Rate, in cfs input: B= 6 ft.
V= Velocity, in fps S= 0.01 ft./ft.
n= Roughness coefficient, Q 2yr= 0.6263 cfs
A= Area of cross section, in sf Q 100yr= 1.41 cfs
R= Hydraulic Radius
S= Slope, in f/f calculate:
requirements: n= 0.2 max Q Match= 0.64(Q 2yr)= 0.400832 cfs
3 to 1 sideslopes
Q match d A R V find: Q Match 0.400 cfs
check: d>0.25 YES
0.000 0.00 0.000 0.000 0.000 select: V= 0.246 fps
0.025 0.05 0.308 0.051 0.081 calculate: L req'd= 74 lin. Ft.
0.082 0.10 0.630 0.104 0.131
0.167 0.15 0.968 0.159 0.173
0.279 0.20 1.320 0.214 0.211
0.416 0.25 1.688 0.270 0.246
0.578 0.30 2.070 0.325 0.279 check stability:
0.764 0.35 2.468 0.380 0.310
0.974 0.40 2.880 0.434 0.338 find: Q 100yr 1.410 cfs
1.206 0.45 3.308 0.486 0.365 check: V<3.0 ? YES
1.460 0.50 3.750 0.536 0.389 d<1.0 ? YES
1.734 0.55 4.208 0.584 0.412
2.027 0.60 4.680 0.629 0.433
2.339 0.65 5.168 0.672 0.453
2.669 0.70 5.670 0.712 0.471
3.014 0.75 6.188 0.750 0.487
3.375 0.80 6.720 0.785 0.502
3.750 0.85 7.268 0.817 0.516
4.138 0.90 7.830 0.847 0.528
4.539 0.95 8.408 0.875 0.540
4.951 1.00 9.000 0.900 0.550
ATrACH MCAT
Ft
r✓11>t sr.q .e IINUTAd FAPER L1141K ILINd fEEI
ull. ..•� Is w Is .o .s so ss NOTEI FOR OPERATIONS OF 15 MINUTES OR LESSt ALL SIGNS PDIIed Speea ImpN
.I•iae tll ss ,s ao w tic tw IH AND CHANNELIZATION DEVICES MAY BE ELIMINATED.
IS 30 )S 40 45 SO SS b5
ula 900[1! A41 KA0 D41&VM •It
i1�11I FOR OPERATIONS Of 60 MINUTES OR LESS, CIIANIIELIZATION 1 105 150 205
11.K.1 wl.t DEVICES ARE REOUIREO-SIGNS ARE RECOMMENDED. r,-
1i�1 ..., �111 IIS I65 226
ow I.aa stow II• 12 125 Ie0 213
hat 4•e•0 SIoIf.L OSI.KL .SILMS
IS.IM S►I10 ..O DIII /.vg,4.1.
�.. ettwpop
Chonlellil
Device spoc§4 11.1
toper WH tangent
]0 IS/tS LO
20 2S/)0 e0
+ 10 MIN
N N o 0 M I o N
A E
250•- 2501- L/3 B R�
I00'
ROAD 500'14AX.
WORK SHOULDER or reverse cone
ANEAp WORK ROAD of toper
ooreow end
WTO-1 W21-5 G20-2A
I8"x48" 18"XI8•• 48' X24"
B/0
B/0 B/0
GENERAL NOTES
1. BUFFER VEHICLE RECOMMENDED -
MAY BE A WORK VEHICLE.
LEGEND
q SIGN LOCATION - TRIPOD MOUNT
0 0 o Ct1ANNElIZING DEVICES
SHOULDER CLOSURE - LOW SPEED .
1 0= BUFFER VEHICLE - RECOMMENDED (35 MPH OR LESS) 9
Traffic Engineer
T.C.P. 6 5 1-95
EXHIBff TO
7
c
u
Right-Of-Woy
Variable
0 Standard Shoulder Plus 1' Curb As Required
K -0.05 F t./Ft
Edge Of Pavement
- eZ MAX
m
M Catch Basihs As Required
_A
n 12" MIN Culvert Pipe Diameter
D
PROFILE CONTROLS
v
x1 ,
O
b ;
�! n ,
,
,
,
(/1 a 'n a
Q Z o z E 1 ;t- 1
NJ
w O
f Right Of-Way Line ; ��
m Povin Limit Right-Of-Way Line
o I ,
,v 4 E .f
� I �
Shld. Line
O 1:25 Taper To Existing U Shld. Line
n 1:25 Toper To Existing
0 --- Toper B a 15'MIN 95
_ ------------------------
----------------------- _ I. 15'MIN
3j
V Asphalt Concrete Pavement —�(L State Hwy Edge Of Pavement
m
O Condition A B C D E I F G7 H i I
Primarily SU & Less — — 10' 30' 15' — — 30' 10'
Primary Combination Vehicle WB 40 = 10' 6 — — 10'
Primary Combination Vehicle WB 50 & Doubles 70' 2QL — — 50' 0'
Primary Combination Vehicle WB 63 2" 31
25' 8' 1 4 10, 1
O
5' 1 451,
�O