HomeMy WebLinkAbout801034003 Drainage Report DRAINAGE AND EROSION/SEDIMENT CONTROL PLAN
FOR
Merrill & Ring U.S. Development L.P.
PROPERTY LOCATION:
SE ¼, SE ¼
Section 3, Township 28 North
Range 1 West, W.M.
Jefferson County, WA,
OWNER:
Merrill & Ring U.S. Development L.P.
P.O. Box. 1058
Port Angeles, WA 98362
(360) 452-2367
:
CIVIL ENGINEER:
Stephen M. Zenovic
ZenOvic & Associates, Inc.
519 S: Peabody St. 1/4
Port Angeles, WA 98362
(360) 417-0501
08/16/01
· Drainage Report Thursday August 16, 2001
Proiect: M&R Timber Conversion~Cen_t~ Jefferson County
·
TABLE OF CONTENTS
DRAINAGE REPORT .................................................................................................................. 1
PROPOSED PROJECT DESCRIPTION
EXISTING CONDITIONS ........................................................................................................
INFILTRATION RATE/SOILS REPORTS ...............................................................................
WELLS AND SEPTIC SYSTEMS ............................................................................................ 2
FUEL TANKS ........................................................................................................................... 2
SUB-BASIN DESCRIPTION ....................................................................................................
ANALYSIS OF THE 100 YEAR FLOOD ..................................................................................
FACILITY SIZING AND DOWNSTREAM ANALYSIS .............................................................
EROSION CONTROL/SEDIMENT REPORT ............................................................................. 1
CONSTRUCTION SEQUENCE AND PROCEDURE .............................................................. 1
SOIL STABILIZATION AND SEDIMENT TRAPPING ............................................................. 1
PERMANENT EROSION CONTROL AND SITE RESTORATION .........................................
INSPECTION SEQUENCE ...................................................................................................... 2
APPENDIX A STORMWATER CALCULATIONS ...................................................................... 1
ENCLOSURE 1 CONTROL OF POLLUTANTS OTHER THAN SEDIMENT ............................ 1
INTRODUCTION ..................................................................................................................... 1
BMP C1.10 PESTICIDE CONTROL ........................................................................................ 2
BMP C1.20 HANDLING OF PETROLEUM PRODUCTS ........................................................4
BMP C1.30 NUTRIENT APPLICATION AND CONTROL ....................................................... 5
BMP C1.40 SOLID WASTE HANDLING AND DISPOSAL .....................................................6
BMP C1.50 USE OF CHEMICALS DURING CONSTRUCTION ............................................ 7
BMP C1.60 MANAGING HAZARDOUS PRODUCTS ............................................................. 8
BMP C1.70 EQUIPMENT WASHING ...................................................................................... 9
BMP C1.80 SPILL CONTROL PLANNING AND CLEANUP ................................................. 10
BMP C1.90 TREATMENT AND DISPOSAL OF CONTAMINATED SOILS .......................... 11
' Drainage Report Thursday August 16, 2001
Project: M&R Timber Conversion, Center, Jefferson County Paqe 1
·
DRAINAGE REPORT
PROPOSED PROJECT DESCRIPTION
The site is a 40-acre parcel located in SE 1/4, SE 1/4, Section :3, Township 28 North, Range 1
West, W.M., Jefferson County, WA, easterly of Larson Lake Road. It is outside the City of Port
Townsend and its Urban Growth boundaries. The site is accessible from Larson Lake Road.
The Project is approximately 5 acres and consists of a stand of thinned timber that will be
harvested. The land will be converted from timber production. Power and telephone utilities will
be extended to the site within the Larson Lake Road right-of-way from existing infrastructure
located in the Larson Lake Road right-of-way.
Stormwater run-off will be directed to two independent temporary stormwater sediment/detention
ponds. The south basin, (Basin #1) consisting of approximately 6.8 acres, will direct run-off to
Pond #1. The north basin, (Basin #2) consisting of approximately 8.9 acres, will direct run-off to
Pond #2 (see attached map).
Water quality will be addressed through the use of sedimentation basins in the bottom of each
temporary sediment/detention pond. Settling volume is based on the 10 year developed flow
from the Santa Barbara Urban Hydrograph 24-hr, Type lA, design storm. Flows will be conveyed
by natural and man-made features to the temporary sediment/detention ponds, where flows will
be regulated by the outlet structures. The structures have sufficient capacity to contain the 100-
year, 24-hr, design storm.
The design goals of this drainage and sediment control plan are: (1) Minimize the impact of this development on the surrounding environment.
(2) Limit stormwater run-off flowrates to existing flowrate levels or less.
These design goals will be met through the following methods:
(1) Impact will be minimized by following the best management practices contained
in The Stormwater Management Manual for the Puget Sound Basin (the Manual).
(2) Run-off flowrates will be limited by reducing the total stormwater run-off flowrate,
from all sources within the project area to those flowrates characteristic of the
same area as-is. In addition, flowrates from the design ?-year storm will be
limited to 50 percent of the existing condition flowrate.
Drainage Repod Monday, August 13, 2001
Project: M&R Timber Conversion, Center, Jefferson County Page 2
EXISTING CONDITIONS
The site is a characterized as a steeply sloped to gradually sloped terrain in timber production.
The steepest slopes are generally located in the eastern portion of the tract.
INFIL TRA T/ON RA TE/SOILS REPORTS
The soil type is classified as Alderwood gravelly sandy loam with an infiltration rate of 0.06-
inches/hour as determined by Soil Survey of Jefferson County Area. No soil logs are available.
Soil of this type is considered not suitable for an infiltration type stormwater system.
WELLS AND SEPTIC SYSTEMS
There are no wells or septic systems located within the project site.
FUEL TANKS
There are no in-use or abandoned fuel tanks on the site.
SUB-BASIN DESCRIPTION
The site is located on the west flank of a hill and slopes generally to the North and West. For
analysis purposes, it was divided into 2 basins to achieve higher accuracy. The stormwater
runoff flows are collected and sent to the sediment/detention ponds where the output is restricted
to "as-is" levels.
ANAL YSIS OF THE 100 YEAR FLOOD
The parcel does not discharge directly into a receiving water, therefore, no 100-year flood
analysis was performed.
FACILITY SIZING AND DOWNSTREAM ANAL YSIS
The stormwater run-off flowrates were calculated for the Type lA (24-hr) storm using the
StormShed analysis program. This program calculates stormwater run-off flowrates using the
Santa Barbara Urban Hydrograph (SBUH) method. Calculation summaries for the 6-month, 2-
year, 10-year, and 100-year 24-hour storms are attached. The stormwater run-off is collected
and routed to one of two trapezoidal ponds for detention. Design discharge flowrates for the
temporary sediment/detention ponds are set at 100% of the "as-is" run-off rates for the 6-month,
10-year and 100-year storms and 50% of the 2-year "as-is" flowrate.
Treatment of the sediment-laden water will be performed by the sedimentation basins
incorporated into the bottom of each temporary sediment/detention pond. They were sized in
accordance with the guidance of the Stormwater Manual. See attached calculations.
The stormwater detention systems discharge to the natural drainage route for the parcel.
Adequate velocity dampening and flow spreading will be provided by the outlet quarry spall pad
to minimize flow concentration.
Overflow/clogged outlet protection will be provided by overflow weirs. No downstream analysis
was performed.
Erosion Control/Sediment Report Thursday, August 16, 2001
, Project: M&R Timber Conversion, Center, Jefferson County Page 1
EROSION CONTROL/SEDIMENT REPORT
The site is a timber production conversion to residential parcels. As such, construction will be
performed in phases. This report will only cover the Initial Phase, which is timber harvesting/land
clearing. Development of each individual lot will require a site specific erosion control plan.
CONSTRUCTION SEQUENCE AND PROCEDURE
The construction element sequence contingent on completion of erosion control facilities shall be as
follows:
1. The silt fence and construction entrance shall be installed prior to any other work.
2. The temporary sediment/detention ponds shall be installed prior to clearing, grubbing or
grading the site.
SOIL STABILIZATION AND SEDIMENT TRAPPING
Sediment will be trapped/Soil stabilized by: 1. Proper installation and maintenance of temporary silt fencing.
2. Grades shall be no steeper than 3 horizontal to 1 vertical.
3. Remove sediment from behind fence when sediment depth exceeds one half of storage
depth.
4. Creation of temporary drainage swales to direct run-off to the temporary
sediment/detention ponds.
5. Temporary sediment/detention ponds sized per Stormwater Management Manual
guidelines.
6. Clean sediment from temporary sediment/detention pond when sediment depth
exceeds one half of storage depth.
7. Proper location of temporary soil stockpiles away from any adjacent ditch.
8. Covering temporary soil stockpiles with plastic sheeting.
Soil lost due to vehicle tracking will be prevented/cleaned up as follows: 1. Proper installation and maintenance of the construction entrance.
2. End of workday sweep or scrape up of soil tracked on road. Soil cleanup will be by
either manual or powered methods.
3. Post-storm sweep or scrape up of any soil washed off site. Soil cleanup will be by
either manual or powered methods.
PERMANENT EROSION CONTROL AND SITE RESTORATION
Erosion will be prevented on the exposed areas as follows: 1. The slope of the landscaping will not exceed 3 horizontal to 1 vertical.
2. The exposed soil will be seeded with grass and/or planted with appropriate plant
species to minimize erosion.
Erosion Control/Sediment Report Thursday, August 16, 2001
, Project: M&R Timber Conversion, Center, Jefferson County Page 2
INSPECTION SEQUENCE
The erosion/sediment control measures necessary to ensure that erosion and sedimentation are
addressed and inspected per the following schedule:
Prior to site clearing inspect the following: 1. Installation of temporary silt fencing, straw bales, and/or mulching as required by terrain
and planned clearing activities.
2. Installation of the construction entrance.
3. Installation of the temporary' sediment/detention ponds.
4. Installation of fabric fence filter at outlet of temporary sediment/detention ponds.
During construction inspect the following: 1. Location of temporary soil stockpiles away from adjacent ditch.
2. Plastic sheeting cover of temporary soil stockpiles in place.
3. Sediment depth in temporary sediment/detention ponds and at base of silt fencinq
Direct contractor to remove sediment when depth exceeds one half of storage deep'th.
4. Roadway for soil tracks. Direct contractor to remove soil tracked on road from previous
workday.
After major rainfall events inspect the following: 1. Temporary drainage swales for proper operation. Direct swale modification as
warranted.
2. Temporary sediment/detention ponds for evidence of overtopping. Direct pond
modification as warranted.
3. Temporary silt fence for damage and direct repairs as required.
4. Sediment depth in temporary sediment/detention ponds and at base of silt fencing.
Direct contractor to remove sediment if depth exceeds one half of storage depth.
5. Inspect efficacy of installed erosion and sedimentation control measures and direct
contractor to provide additional facilities as warranted°
6. Soil washed off site. Direct contractor to remove.
The responsible person for project site inspection is not currently known. The name and phone
number will be provided to the County by the Owner.
APPENDIX A Drainage Repod Calculations Thursday, August 16, 2001
· Project: M&R Timber Conversion, Center, Jefferson County Page 1
APPENDIX A STORMWATER CALCULATIONS
Project Precips
6 mo 1.34 in
2 yr 2.10 ~n
5 yr 2.50 ~n
10 yr 2.80 ~n
25 yr 3.16 ~n
100 yr 3.70 ~n
BASIN I SUMMARY
6 mo Match Q: 0.0880 cfs Peak Out Q: 0.0893 cfs - Peak Stg: 101.60 ft - Active Vol: 3828.07 cf
2 yr Match Q: 0.1839 cfs Peak Out Q: 0.1785 cfs - Peak Stg: 103.66 ft - Active Vol: 0.26 acft
10 yr Match Q: 0.8194 cfs Peak Out Q: 0.5573 cfs - Peak Stg: 103.74 ft - Active Vol: 0.27 acft
100 yr Match Q: 1.5714 cfs Peak Out Q: 1.4628 cfs - Peak Stg: 103.83 ft - Active Vol: 0.28 acft
Summary Report of all BASIN 1 RLPool Data
BasinlD Peak Q Peak T Peak Vol Area Method Raintype Event
....... (cfs) (hrs) (ac-fi) ac /Loss
Pre-Dev Basin 1 0.0880 17.00 0.1082 6.77 SBUH/SCS TYPE1A 6 mo
Pre-Dev Basin I 0.3678 8.67 0.3319 6.77 SBUH/SCS TYPE1A 2 yr
Pre-Dev Basin 1 0.8194 8.50 0.5941 6.77 SBUH/SCS TYPEIA 10 yr
Pre-Dev Basin I 1.5714 8.17 0.9783 6.77 SBUH/SCS TYPE1A 100 yr
Basin I 0.1817 9.00 0.1907 6.77 SBUH/SCS TYPE1A 6 mo
Basin I 0.6330 8.50 0.4757 6.77 SBUH/SCS TYPEIA 2 yr
Basin 1 1.1697 8.17 0.7835 6.77 SBUH/SCS TYPE1A 10 yr
Basin I 1.9750 8.17 1.2141 6.77 SBUH/SCS TYPE1A 100 yr
Drainage Area: Pre-Day Basin 1
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur: 24.00 hrs Intv: 10.00 min
Area CN TC
Pervious 6.7700 ac 79.15 0.64 hrs
Impervious 0.00 ac 0.00 0.00 hrs
Total 6.7700 ac
Supporting Data:
Pervious CN Data:
Young DF 81.00 4.2700 ac
Mature DF 76.00 2.5000 ac
Pervious TC Data:
FIowtype: Description: Length: Slope: Coeff: Travel Time
Sheet stad 200.00 ft 25.00% 0.80 29.26 rain _
Shallow shallow 165.00 fl 5.00% 3.00 4.10 min
Channel Natural swale 100.00 ft 10.00% 5.00 1.05 min
Channel Natural bench 200.00 ft 5.00% 5.00 2.98 min
Channel Ditch 200.00 ft 5.00% 20.00 0.75 min
Drainage Area: Basin 1
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur: 24.00 hrs Intv: 10.00 min
Area CN TC
Pervious 6.77 ac 84.52 0.80 hrs
Impervious 0.00 ac 0.00 0.00 hrs
Total 6.77 ac
APPENDIX A Drainage Report Calculations Thursday, August 16, 2001
Project: M&R Timber Conversion, Center, Jefferson County Page 2
Supporting Data:
Pervious ON Data:
Young DF forest 81.00 4.10 ac
Cleared Lot 90.00 2.50 ac
Gravel Road 89.00 0.17 ac
Pervious TC Data:
Flow type: Description: Length: Slope: Coeff: Travel Time
Sheet start 200.00 fi 10.00% 0.80 42.21 min
Shallow shallow 165.00 fi 11.00% 3.00 2.76 min
Channel Natural swale 100.00 ft 9.00% 5.00 1.11 min
Channel Ditch 450.00 ft 5.00% 20.00 1.68 min
HydlD Peak Q Peak T Peak Vol Cont Area
....... (cfs) (hrs) (ac-fi) (ac)
Dev-out-Cmo 0.09 24.33 0.1899 6.7700
Dev-out-2yr 0.18 24.33 0.4750 6.7700
Dev-out- 10yr 0.51 13.50 0.7827 6.7700
Dev-out- 100yr 1.31 9.83 1.2133 6.7700
6 mo-Orif 1 a-OutHyd 0.09 24.33 0.1898 6.7700
2 yr-Orif la-OutHyd 0.13 24.33 0.4039 5.7589
10 yr~Orif la-OutHyd 0.14 12.17 0.4327 3.7428
100 yr-Orif la-OutHyd 0.14 9.50 0.4478 2.4992
6 mo-Orif lb-OutHyd 0.00 0.00 0.0000 0.0000
2 yr~Orif 1 b-OutHyd 0.04 24.33 0.0709 1.0111
10 yr-Orif lb-OutHyd 0.04 12.17 0.0877 0.7588
100 yr-Orif I b-OutHyd 0.05 9.50 0.0933 0.5209
6 mo-Weir 1-OutHyd 0.00 0.00 0.0000 0.0000
2 yr-Weir 1-OutHyd 0.00 0.00 0.0000 0.0000
10 yr-Weir 1-OutHyd 0.38 12.17 0.2623 2.2685
100 yr-Weir 1-OutHyd 1.28 9.50 0.6720 3.7499
Node ID: Trap 1
Desc: Trap. pond
Start El: 100.00 fi Max El: 106.00 ft
Contrib Basin: Contrib Hyd:
Length ss 1 ss2 Width ss3 ss4
75.00 ft 3.00h:lv 3.00h:lv 25.00 ft 3.00h:lv 3.00h:lv
Control Structure ID: Combo la -Combination Control Structure
Note: Elevations are arbitraw for analysis purposes and do not represent design elevations in the
field.
Descrip: Vert Orifice and Weir
Start El Max El Increment
100.00 ft 106.00 ft 0.10
ID List: Orif la Orif 1 b Weir 1
Split: Split OutHyd into component hydrographs.
Control Structure ID: Orif la - Vertical oriented orifice
Descrip: Vert Orifice
Start El Max El Increment
100.00 ft 106.00 ft 0.10
Weir Area: 0.0144 sf Coefficient: 0.6100
Control Structure ID: Orif lb - Vertical oriented orifice
Descrip: Vert Orifice
Star! El Max El Increment
102.00 ft 106.00 fl 0.10
Weir Area: 0.0069 sf Coefficient: 0.6100
APPENDIX A Drainage Report Calculations Thursday, August 16, 2001
· Project: M&R Timber Conversion, Center, Jefferson County Page 3
Control Structure ID: Weir 1 -Overflow riser
Descrip: riser
Start El Max El Increment
103.67 ft 106.00 ft 0.10
Riser Dia: 24.00 in Orif Coeff: 3.78 Weir Coeff: 9.74
APPENDIX A Drainage Report Calculations Thursday, August 16, 2001
Project: M&R Timber Conversion, Center, Jefferson County Page 4
BASIN 2 SUMMARY
6 mo Match Q: 0.1207 cfs Peak Out Q: 0.1229 cfs - Peak Stg: 101.72 ft - Active Vol: 4162.37 cf
2 yr Match Q: 0.2570 cfs Peak Out Q: 0.2483 cfs - Peak Stg: 104.04 ft - Active Vol: 0.30 acft
10 yr Match Q: 1.1253 cfs Peak Out Q: 0.7453 cfs - Peak Stg: 104.17 ft - Active Vol: 0.32 acft
100 yr Match Q: 2.1355 cfs Peak Out Q: 1.9757 cfs - Peak Stg: 104.28 ft - Active Vol: 0.33 acft
Summary Report of all BASIN 2 RLPool Data
BasinlD Peak Q Peak T Peak Vol Area Method Raintype Event
....... (cfs) (hrs) (ac-fi) ac /Loss
Pre-Dev Basin 2 0.1207 17.00 0.1502 8.93 SBUH/SCS TYPE1A 6 mo
Pre-Dev Basin 2 0.5140 8.67 0.4518 8.93 SBUH/SCS TYPE1A 2 yr
Pre-Dev Basin 2 1.1253 8.17 0.8027 8.93 SBUH/SCS TYPE1A 10 yr
Pre-Dev Basin 2 2.1355 8.17 1.3148 8.93 SBUH/SCS TYPE1A 100 yr
Basin 2 0.2165 9.17 0.2378 8.93 SBUH/SCS TYPE1A 6 mo
Basin 2 0.7855 8.50 0.6048 8.93 SBUH/SCS TYPE1A 2 yr
Basin 2 1.4743 8.50 1.0046 8.93 SBUH/SCS TYPE1A 10 yr
Basin 2 2.5173 8.17 1.5662 8.93 SBUH/SCS TYPE1A 100 yr
Drainage Area: Pre-Der Basin 2
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur: 24.00 hrs Intv: 10.00 min
Area CN TC
Pervious 8.93 ac 79.60 0.64 hrs
Impervious 0.00 ac 0.00 0.00 hrs
Total 8.93 ac
Supporting Data:
Pervious CN Data:
Young DF 81.00 6.43 ac
Mature DF 76.00 2.50 ac
Pervious TC Data:
Flow type: Description: Length: Slope: Coeff: Travel Time
Sheet start 200.00 ft 25.00% 0.8000 29.26 min
Shallow shallow 165.00 ft 5.00% 3.00 4.10 min
Channel Natural swale 100.00 ft 10.00% 5.00 1.05 min
Channel Natural bench 200.00 fi 5.00% 5.00 2.98 min
Channel Natural Swale 200.00 ft 5.00% 20.00 0.75 min
Drainage Area: Basin 2
Hyd Method: SBUH Hyd Loss Method: SCS CN Number
Peak Factor: 484.00 SCS Abs: 0.20
Storm Dur: 24.00 hrs Intv: 10.00 min
Area CN TC
Pervious 8.93 ac 83.95 0.80 hrs
Impervious 0.00 ac 0.00 0.00 hrs
Total 8.93 ac
Supporting Data:
Pervious CN Data:
Young DF forest 81.00 5.9500 ac
Cleared Lot 90.00 2.5000 ac
Gravel Road 89.00 0.4800 ac
Pervious TO Data:
Flow type: Description: Length: Slope: Coeff: Travel Time
Sheet start 200.00 ft 10.00% 0.80 42.21 min
Shallow shallow 165.00 ft 9.00% 3.00 3.06 min
Channel Natural Swale 200.00 ft 9.00% 5.00 2.22 min
Channel Natural Swale 150.00 ft 10.00% 20.00 0.40 min
APPENDIX A Drainage Report Calculations Thursday, August 16, 2001
· Project: M&R Timber Conversion, Center, Jefferson County Page 5
HydlD Peak Q Peak T Peak Vol Cont Area
....... (cfs) (hrs) (ac-fi) (ac)
2-Dev-out-6m o 0.12 24.17 0.2375 8.9300
2-Dev-out-2yr 0.25 24.17 0.6045 8.9300
2-Dev-out- 10yr 0.75 11.83 1.0042 8.9300
2-Dev-out-100yr 1.98 9.33 1.5658 8.9300
6 mo-Orif 2a-OutHyd 0.12 24.17 0.2373 8.9300
2 yr-Orif 2a-OutHyd 0.19 24.17 0.5061 7.4784
10 yr-Orif 2a-OutHyd 0.19 11.83 0.5486 4.8788
100 yr-Orif 2a-OutHyd 0.19 9.33 0.5697 3.2495
6 mo-Orif 2b-OutHyd 0.00 0.00 0.00 0.00
2 yr-Orif 2b-OutHyd 0.06 24.17 0.0982 1.4516
10 yr-Orif 2b-OutHyd 0.06 11.83 0.1197 1.0649
100 yr-Orif 2b-OutHyd 0.06 9.33 0.1268 0.7233
6 mo-Weir 2-OutHyd 0.00 0.00 0.00 0.00
2 yr-Weir 2-OutHyd 0.00 0.00 0.0000 0.0000
10 yr-Weir 2-OutHyd 0.49 11.83 0.3358 2.9863
100 yr-Weir 2-OutHyd 1.72 9.33 0.8692 4.9573
Node ID' Trap 2
Desc: Trap. pond
Start El: 100.00 fi Max El: 106.00 ft
Contrib Basin: Contrib Hyd:
Length ss 1 ss2 Width ss3 ss4
75.000 fi 3.00h:lv 3.00h:lv 25.00 ft 3.00h:lv 3.00h:lv
Control Structure ID: Combo 2a -Combination Control Structure
Note: Elevations are arbitrary for analysis purposes and do not represent design elevations in the
field.
Descrip: Veal Orifice and Weir
Start El Max El Increment
100.00 ft 106.00 ft 0.10
ID List: Orif 2a Orif 2b Weir 2
Split: Split OutHyd into component hydrographs.
Control Structure ID: Orif 2a - Vertical oriented orifice
Descrip: Vert Orifice
Start El Max El Increment
100.00 ft 106.00 fl 0.10
Weir Area: 0.0192 sf Coefficient: 0.61
Control Structure ID: Orif 2b - Vertical oriented orifice
Descrip: Vert Orifice
Start El Max El Increment
102.00 ft 106.00 ft 0.10
Weir Area: 0.0085 sf Coefficient: 0.61
Control Structure ID: Weir 2 - Overflow riser
Descrip: notched riser
Start El Max El Increment
104.08 ft 106.00 ft 0.10
Riser Dia: 24.00 in Orif Coeff: 3.78 Weir Coeff: 9.74
APPENDIX A Drainage Report Calculations Thursday, August 16, 2001
Project: M&R Timber Conversion, Center, Jefferson County Page 6
CONVEYANCE CALCULATIONS
MANNING'S EQUATION FOR TRAPEZOIDAL CHANNEL
Zenovic & Associates
519 South Peabody, Suite fl4
Port Angeles, WA 98362
~.~ ~...~:..~ ..~. ,.v ~ ,.., ,..
BOTTOM W= ~FT SIDE SLOPE =~(HN)'~" ~ ' ~ ,~
MAXIMUM ~~~!. FT n = S =
DEPTH = .~
d (ft) I Aw (ft) I Pw (ft) I Rh (ft) J V (fps) I o (cfs)
0.00 0.00 2.00 0.00 0.00 0.00
0.08 0.19 2.53 0.07 0.19 0.03
0.17 0.42 3.05 0.14 0.28 0.12
0.25 0.69 3.58 0.19 0.35 0.24
0.33 1.00 4.11 0.24 0.41 0.41
0.42 1.35 4.64 0.29 0.46 0.63
0.50 1.75 5.16 0.34 0.51 0.90
0.58 2.19 5.69 0.38 0.56 1.22
0.67 2.67 6.22 0.43 0.60 1.60
0.75 3.19 6.74 0.47 0.64 2.04
0.83 3.75 7.27 0.52 0.68 2.54
0.92 4.35 7.80 0.56 0.71 3.11
1.00 5.00 8.32 0.60 0.75 3.75
1.08 5.69 8.85 0.64 0.78 4.46
1.17 6.42 9.38 0.68 0.82 5.25
1.25 7.19 9.91 0.73 0.85 6.11
1.33 8.00 10.43 0.77 0.88 7.06
1.42 8.85 10.96 0.81 0.91 8.09
1.50 9.75 11.49 0.85 0.94 9.21
1.58 10.69 12.01 0.89 0.97 10.42
1.67 11.67 12.54 0.93 1.00 11.71
1.75 12.69 13.07 0.97 1.03 13.11
1.83 13.75 13.60 1.01 1.06 14.60
1.92 14.85 14.12 1.05 1.09 16.19
2.00 16.00 14.65 1.09 1.12 17.88
INTERMEDIATE VALUE - ~~ 3.73 7.25 0.51 0.68 2.52
*NOTE: MANNINGS RESULTS MAY BE UNRELIABLE FOR
VELOCITY GREATER THAN 10 FPS.
APPENDIX A Drainage Report Calculations Thursday, August 16, 2001
Project: M&R Timber Conversion, Center, Jefferson County Page 7
iMANNING'S EQUATION FOR PIPE FLOWING PART FULL
Zenovic & Associates
519 South Peabody, Suite #4
Port Angeles, WA 98362
PIPE D = ~in n =~ S =~
d(in) I Aw(ft) I Pw(ft) I Rh(ft) I V(fps) I Q(cfs)
0.00 0.00 0.00 0.00 0.00 0.00
0.50 0.01 0.41 0.03 1.59 0.02
1.00 0.03 0.59 0.05 2.49 0.08
1.50 0.06 0.72 0.08 3.22 0.18
2.00 0.09 0.84 0.10 3.84 0.33
2.50 0.12 0.95 0.13 4.39 0.52
3.00 0.15 1.05 0.15 4.88 0.75
3.50 0.19 1.14 0.17 5.33 1.01
4.00 0.23 1.23 0.19 5.73 1.31
4.50 0.27 1.32 0.20 6.09 1.64
5.00 0.31 1.40 0.22 6.41 t .99
5.50 0.35 1.49 0.24 6.71 2.35
6.00 0.39 1.57 0.25 6.97 2.74
6.50 0.43 1.65 0.26 7.20 3.13
7.00 0.48 1.74 0.27 7.40 3.52
7.50 0.52 1.82 0.28 7.57 3.91
8.00 0.56 1.91 0.29 7.71 4.29
8.50 0.59 2.00 0.30 7.82 4.65
9.00 0.63 2.09 0.30 7.90 4.99
9.50 0.67 2.19 0.30 7.94 5.29
10.00 0.70 2.30 0.30 7.94 5.55
10.50 0.73 2.42 0.30 7.89 5.75
11.00 0.75 2.56 0.30 7.78 5.87
11.50 0.77 2.73 0.28 7.58 5.87
12.00 0.79 3.14 0.25 6.97 5.47
MAX FLOW VALUE -~~ 0.77 2.71 0.28 7.60 5.87
*NOTE: MANNINGS RESULTS MAY BE UNRELIABLE FOR
VELOCITY GREATER THAN 10 FPS.
APPENDIX A Drainage Repod Calculations Thursday, August 16, 2001
Project: M&R Timber Conversion, Center, Jefferson County Page 8
SETTING VOLUME CALCULATIONS
Settling Area (SA) = 1.2'Qlo = 1.2'Qlo.= 1250 s.f./cfs
-- __
Vstd 0.096
Q10 inflow = 1.48 cfs
SA = 1250'1.48= 1850 s.f.
Required Settling Volume = 2 ft (min.) * 1850 = 3700 c.f.
Design Settling Volume (neglecting pond side slope -conservative)
Design Settling Area = 25 ft * 75 ft = 1875 s.f.
Design Settling Volume = 2 ft * 1875 s.f. = 3750 cf
i
Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 1
ENCLOSURE I CONTROL OF POLLUTANTS OTHER THAN
SEDIMENT
INTRODUCTION
Potential pollutants other than sediment associated with construction activity include numerous
hazardous wastes as well as other solid and liquid wastes. Hazardous wastes include pesticides
(insecticides, fungicides, herbicides, rodenticides etc.) petrochemicals (oils, gasoline, asphalt
degreaser, etc.) and other construction chemicals such as concrete products, sealer, paints and
wash water associated with these products. Other wastes include paper, wood, garbage,
sanitary wastes, and fertilizer.
Practices must be used that prevent these potential pollutants from leaving the construction site.
Good erosion and sediment control, coupled with stormwater management, will deter the
movement of large amounts of sediment off the site. (It must be recognized, however, that
pollutants carried in solution in runoff water, or fixed with sediment crystalline structures (e.g.,
crystalline clays), will be carried through the erosion and sediment control defenses.) Pollutants
such as oils, waxes, and water-insoluble pesticides, form surface films on water and on solid
particles, and also, oil films serve as a medium for concentrating water-soluble insecticides.
Other than by use of very costly water-treatment facilities or long runoff water detention periods,
these pollutants become nearly impossible to control once present in the runoff.
The most economical and effective controls for pollutants other than sediment generated on
construction sites, are the exercise of good "housekeeping" practices, and an awareness by
construction workers, planners, engineers, and developers .of the need and purpose of
compliance with federal, state, and local regulations.
Ways must be found to protect ponds, wetlands, lakes, streams, and coastal and estuarine water
bodies from damage by sediment and other pollutants generated during construction activities.
The physical characteristics of the construction site have a major bearing on the potential severity
of pollution from construction activities. As in the case of sediment, the vast majority of runoff
coming from a construction site is dependent upon hydrologic factors. These include the amount,
intensity, and frequency of rainfall; the infiltration rate of the soil; surface roughness; and the
length and steepness of the ground slope. Large areas stripped of vegetation, long slopes, steep
slopes, tight soils, and high intensity of rainfall are all factors conducive to heavy runoff.
Another physical factor influencing the severity of pollution is the proximity of the pollutant, or
potential pollutant, to the receiving water. For example, fedilizers applied to a streambank are
more apt to cause water pollution than fertilizers applied to a slope well upland of the waterway.
- _
Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 2
BMP C1.10 PESTICIDE CONTROL
Although the word "pesticide" has come to mean only those chemicals which attack insect
populations, here the word is used to include herbicides and rodenticides as well as chemicals
commonly known as pesticides. Insecticides, rodenticides, and herbicides have historically been
used on construction sites to increase health and safety, maintain a pleasant environment, and
reduce maintenance and fire hazards. Often, rodents are attracted to construction sites and
rodenticides are used
Pesticides shall only be used in conjunction with Integrated Pest Management (IPM). IPM utilizes
a needs assessment which determines which method to use and the necessity of controlling a
pest population. Pesticides should be the tool of last resort; methods which are the least
disruptive to the environment and to human health should be used first.
If pesticides must be used, clearance for use of any of these chemicals is often required by
restrictive federal and state regulations. All pesticides should be stored and applied in
accordance with regulations of the State Department of Agriculture, WAC 16-228-185. EPA has
produced a pamphlet "Suspended, Cancelled and Restricted Pesticides" (Jan 1985), which
includes information on many pesticides. As it is more than 15 years old, it is wise to check with
EPA's Region 10 Pesticides Branch, Seattle, if any questions regarding the use of pesticides
arise. An awareness of the need to adhere to recommended dosages, type of application
equipment, time of application, cleaning of application equipment, and safe disposal of these
chemicals, will go far in limiting the pollution of waterways. Application rates should conform to
registered label direction. Many of these compounds are considered "Dangerous Wastes" and
must be disposed of properly. Disposal of excess pesticides and pesticide-related wastes should
conform to registered label directions for the disposal and storage of pesticides and pesticide
containers set forth in applicable federal, state and local regulations. General disposal
procedures are:
· Dispose of through a licensed waste management firm or treatment, storage and disposal
company (TSD).
· Use up, or give away to garden center, landscape service, etc.
· Triple rinse containers before disposal, reuse rinse waters as product.
"Hazardous Waste Pesticides-Determining if your Pesticide is a Hazardous Waste," booklet #89-
14 provides guidance and is available from Washington State Depadment of Ecology (WSDOE)
Publications Office. For more information call the Hazardous Substance Information Hotline
(800-633-7585)
Pesticide storage areas on the construction site should be protected from the elements, from
vandals, and from the curious. Warning signs should be placed in areas recently sprayed or - -
treated with the most dangerous pesticides. Persons involved in mixing and application of these
chemicals, to be in compliance with the law, must wear suitable protective clothing.
Other practices include:
· Set aside a locked, weather-resistant storage area.
· Lids should be tightly closed.
· Keep in a cool, dry place. Many pesticides rapidly lose their effectiveness if stored in
areas exposed to heat.
Erosion and Sediment Control Report Thursday, August 16, 2001
, Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R: Timber Conversion, Center, Jeff~m'on Count~ ~ ~
· In case of a leak, put original container into a larger container and label it properly.
· Check containers periodically for leaks or deterioration.
· Keep a list of products in storage.
· Use plastic sheeting to line the area.
· The applicator must follow the notification requirements of the WDSA. Neighbors on
properties adjacent to the one being sprayed should also be notified prior to spraying.
· All storage sheds, dumpsters or other storage facilities should be regularly monitored for
leaks and repaired as necessary. Remind workers during subcontractor or safety
meetings about proper storage and handling of materials.
Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 4
BMP Cl.20 HANDLING OF PETROLEUM PRODUCTS
Petroleum products are widely sued during construction activities. They are used as fuels and
lubricants for vehicular operations, power tools, and general equipment maintenance. The
pollutants include oils, fuels such as gasoline, diesel oil, kerosene, lubricating oils, and grease.
Asphalt paving can be a pollutant source as it continues to release various oils for a considerable
length of time. Most of these pollutants adhere to soil particles and other surfaces easily.
One of the best modes of control is to retain sediments containing oil on the construction site.
Soil erosion and sediment control practices can effectively accomplish this. Improved
maintenance and safe storage facilities will reduce their chances of contaminating construction
sites. One of the greatest concerns confronting uses of these petroleum products is the method
for waste disposal. Oil and oily wastes such as crankcase oil, cans, rags, and paper dropped in
oils and lubricants, can be best disposed of in proper receptacles or recycled (call 1-800-
RECYCLE). Waste oil for recycling should not be mixed with degreasers, solvents, antifreeze, or
brake fluid. The dumping of these wastes in sewers and other drainage channels is illegal and
could result in fines or job shutdown. A further source of these pollutants is leaky vehicles.
Proper maintenance of equipment and installation of proper stream crossing will further reduce
pollution of water by these sources. Stream crossing should be minimized through proper
planning of access roads.
Guidelines for storing petroleum products are as follows:
Store products in weather-resistant sheds where possible.
· Create shelter around area with cover and wind protection.
· Line the storage area with double layer of plastic sheeting or similar material.
· Create impervious berm around the perimeter.
· Capacity of bermed area should be 110 percent of largest container. All products should
be clearly labeled.
· Keep tanks off the ground.
· Keep lids securely fastened.
· Contact local fire marshal for more information.
· Post information for procedures in case of spills. Persons trained in handling spills
should be on-site or on call at all times
· Materials for cleaning up spills should be kept on-site and easily available. Spills should
be cleaned up immediately and the contaminated material properly disposed of.
·Specify a staging area for all vehicle maintenance activities. This area should be located
away from all drainage courses.
· All storage sheds, dumpsters or other storage facilities should be regularly monitored for
leaks and repaired as necessary. Remind workers during subcontractor or safety
meetings about proper storage and handling of materials.
Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 5
BMP Cl.30 NUTRIENT APPLICATION AND CONTROL
Inorganic nutrient pollution is most often caused by fertilizers used in revegetating graded areas.
The use of proper soil-stabilization measures, sediment control, and stormwater detention
structures can be effective means of keeping these materials out of waterways. Only small
amounts of inorganic nutrients are beneficial to the productivity of waterways, while excess
amounts result in over-enrichment (eutrophication).
Nutrient pollution can be minimized by working fertilizers and liming materials into the soil to
depths of 4 to 6 inches, and by proper timing of the application. Hydro-seeding operations, in
which seed, fertilizers and lime are applied to the ground surface in a one-step operation, are
more conducive to nutrient pollution than are conventional seedbed-preparation operations,
where the fertilizers and lime are tilled into the soil. In the case of surface dressings, control can
be achieved by applying the required quantity of fertilizer in more than one operation. For
example, an area requiring an application of 500 lbs. per acre of fertilizer could be dressed with
about 125 lbs. per acre at four separate times over the growing season.
Use of fertilizers containing little or no phosphorus may be required by local authorities if the
development is near sensitive water bodies. In any event, great care should be taken to use only
the minimum amount of phosphorus needed, as determined by soil tests, or advice from the local
Conservation District or Soil Conservation Service.
Near sensitive surface waters, the addition of lime can affect the pH (or acidity) of runoff and
receiving waters. Importation of topsoil is better than heavily liming and fertilizing exposed
subsoil.
Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 6
BMP Cl.40 SOLID WASTE HANDLING AND DISPOSAL
Solid waste is one of the major pollutants caused by construction. Solid waste is generated from
trees and shrubs removed during land clearing for construction of streets and parking facilities,
and during the installation of structures. Other wastes include wood and paper from packaging
and building materials, scrap metals, sanitary wastes, rubber, plastic and glass pieces, masonry
products, and others. Food containers such as beverage cans, coffee cups, lunch-wrapping
paper and plastic, cigarette packages, leftover food, and aluminum foil contribute a substantial
amount of solid waste to the construction site.
The major control mechanism for these pollutants is to provide adequate disposal facilities.
Collected solid waste should be removed and disposed of at authorized disposal areas. Frequent
garbage removal helps maintain construction sites in a clean and attractive manner. Waste
containers should be labeled and located in a covered area. Lids should be kept closed at all
times. Any useful materials should be salvaged and recycled. For instance, masonry waste can
be used for filling borrow pits, trees and brush from land-clearing operations can be converted
into woodchips through mechanical chippers and then used as mulch in graded areas. Sanitary
facilities must be convenient and well maintained to avoid indiscriminate soiling of adjacent areas.
Selective (rather than wholesale) removal of trees is helpful in conservation of soil and reduction
of wood wastes. Indiscriminate removal of trees and other beneficial vegetation should be
avoided.
Soil erosion and sediment control structures capture much of the solid waste from construction
sites. Constant removal of litter from these structures will reduce the amount of solid waste
despoiling the landscape. The extension of local and state anti-litter ordinances to cover
construction sites is also a viable control mechanism. Adherence to these regulations by
construction personnel reduces unnecessary littering through carelessness and negligence.
Erosion and Sediment Control Repod Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 7
BMP C1.50 USE OF CHEMICALS DURING CONSTRUCTION
Many types of chemicals may be used during construction activities. These chemical pollutants
include paints, acids for cleaning masonry surfaces, cleaning solvents, asphalt products, soil
additives used for stabilization and other purposes, concrete-curing compounds, and many
others. These materials are carried by sediment and runoff from construction sites.
A large percentage of these pollutants can be effectively controlled through implementation of
source control soil erosion and sedimentation control practices. By using only the recommended
amounts of these materials and applying them in a proper manner, pollution can be further
reduced. As in the case of other pollutants, good housekeeping is the most impodant means of
controlling pollution.
The correct method of disposal of wastes varies with the material. Wash-up waters from water-
based paints may go into a sanitary sewer, but wastes from oil-based paints, cleaning solvents,
thinners, and mineral spirits must be disposed of through a licensed waste management firm or
TSD. Disposal of concrete products, additives, and curing compounds depends on the product.
Information is available from the local health department or the Hazardous Substance Information
Hotline (1-800-633-7585).
Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 8
BMP C1.60 MANAGING HAZARDOUS PRODUCTS
· Buy and use only what is needed. Leftovers need to be stored, re-used, given away,
recycled or disposed of safely.
· Read labels and follow directions on the label. Hazardous products may be labeled:
Danger Poisonous Volatile
Combustible Caustic Explosive
Warning Corrosive Flammable
Caution
· Try to keep products in original containers and always keep them well-labeled. If the
product must be transferred to smaller containers, use the proper size funnel and avoid
spills. Label all containers.
· Labels can fall off with weathering. To prevent, cover with transparent tape. To relabel,
use a metal tag attached to the container or use a stencil and spray paint.
· Do not mix chemical substances unless recommended by the manufacturer.
· Use in well-ventilated areas. Protect skin, eyes, nose, and mouth when necessary by
wearing gloves, respirator, or other protective clothing.
· Keep corrosive liquids away from flammable liquids.
· Look for nontoxic or less toxic options (check with the State Department of Ecology Office
of Waste Reduction at 360-407-6000).
· Use all of the product before disposing of the container.
· There are private firms that specialize in the cleanup of spills.
· Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 9
BMP C1.70 EQUIPMENT WASHING
Thinners or solvents should not be discharged into the sanitary or storm sewer systems when
cleaning large machine parts where discharge of water is required. Use alternative methods for
cleaning larger equipment parts such as high pressure, high temperature water washes, or steam
cleaning.
Equipment washing detergents can be used and wash water discharged into the sanitary system
if grit is removed from the solution first. The water discharged into the sewer must not exceed the
discharge limits set by the Sewer Authority.
Small parts, can be cleaned with degreasing solvents which are reused after filtering or recycled.
These solvents should not be discharged into any sewer. Further information is available from
the Department of Ecology.
. Erosion and Sediment Control Repod Thursday, August 16, 2001
Enclosure 1: Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 10
BMP C1.80 SPILL CONTROL PLANNING AND CLEANUP
Construction site supervisors shall adopt a spill control plan and identify persons responsible for
implementing the plan if a spill of a dangerous or hazardous waste should occur. Any spill that
occurs, regardless of the size and/or type of spill, should be reported to the following agencies:
· If the spill of a hazardous substance could reach surface waters, the following agencies
must be notified (there are fines for failing to notify):
National Response Center 1-800-424-8802 (24-hour)
· Locally, notify the regional Department of Ecology Offices:
Northwest Region - Redmond 425-649-7000 (24-hour)
Southwest Region -Olympia 360-407-6300 (24-hour)
· Within the City of Bellevue
Storm & Surface Water Utility 425-452-2977 (24-hour)
· For spills within salt water
U.S. Coast Guard: 425-252-5281
There are fines for failing to notify the appropriate authority when a spill occurs.
· Some of the important components of a spill control plan are:
· Establish who to notify in the event of a spill, particularly if it is hazardous.
· Provide specific clean-up instructions for different products handled on site.
· Assign a person to be in charge of clean-up assistance.
· Prepare spill containment and clean-up lists that are easy to find and use.
· Post a summary of the clean-up plan at appropriate locations.
· If a spill occurs, demobilize it as quickly as possible.
· If there is a chance that the spill could enter a storm drain or sewer, plug the inlet and
turn off or divert any incoming water.
· Cover the spill with absorbent material such as kitty litter or sawdust. Do not use straw.
Dispose of the used absorbent per Ecology or manufacturer's instructions. If the spill is
flammable, dispose of as directed by the local fire marshal.
· Keep the area well ventilated.
, Erosion and Sediment Control Report Thursday, August 16, 2001
Enclosure 1' Control of Pollutants Other Than Sediment
Project: M&R Timber Conversion, Center, Jefferson County Page 11
BMP C1.90 TREATMENT AND DISPOSAL OF CONTAMINA TED SOILS
Contaminated ground water or soil may be encountered during earthwork activities or by the spill
or leak of a hazardous product. The contaminant may be known or unknown. Sampling and
laboratory tests may be required to determine whether a landfill can accept the contaminated soil.
In some cases it is possible to reduce the hazardous potential of the soil by aerating it, for
example. Local health departments can supply the necessary procedures. Private firms can also
be consulted for disposal.
The Model Toxics Control Act, Ch. 70.105 RCW, requires that Ecology's Toxic Cleanup Program
be notified if contaminated soil or ground water is encountered during a project.