HomeMy WebLinkAboutStormwater Report and Calculations 05-20-20 STORMWATER MANAGEMENT
DESIGN REPORT
FOR:
FLANDERS MILL APARTMENTS
LOT 1, BLOCK 25
FLANDERS MILL SUBDIVISION
BOZEMAN, MT
Prepared By:
M
MADISON
ENGINEERING
Madison Engineering
895 Technology Drive, Suite 203
Bozeman, MT 59718
(406) 586-0262
JANUARY 2020
REVISED MAY 2020
STORMWATER MANAGEMENT
DESIGN REPORT
FOR:
FLANDERS MILL APARTMENTS
LOT 1 , BLOCK 25
FLANDERS MILL SUBDIVISION
BOZEMAN, MT
uj
Q
Uiv'N-����
Madison Engineering
895 Technology Blvd Ste 203
Bozeman, MT 59718
(406) 586-0262
JANUARY 2020
REVISED MAY 2020
FLANDERS MILL APARTMENTS MASTER SITE PLAN
LOT 1, BLOCK 25, FLANDERS MILL SUBDIVISION
STORMWATER DESIGN REPORT
This design report will give an overview of the proposed stormwater system for the Flanders
Mil] Apartments Master Site Plan located in Lot 1, Block 25 of Flanders Mill Subdivision,
Bozeman, Montana.
The project site is broken into three phases of development. The water, storm and sanitary
infrastructure will be installed entirely during Phase 1 along with associated parking lot
improvements and buildings in Phase 1. Phases 2 and 3 will consist of associated parking lot
improvements and buildings in those areas. The first phase is located at the north end of the site,
which is the lowest in elevation. The stormwater collection system for the entire project consists
of two inlets that surface drain all three development phases to an underground ADS retention
system. The two inlets and retention system are located in Phase 1. This simplifies the
stormwater design considerations for the phased development because new pavement and
buildings constructed during later phases will simply contribute to the existing system installed
during Phase 1 which has been sized for the entire three phases of development.
Two post development drainage areas were created within the project. Runoff from Drainage
Areas 1 and 2 will be contained on site in Retention Facility 1. This retention facility will be
comprised of an ADS SC-740m Stormtech system located under a portion of the parking lot in
the northwest corner of the site. The system will be equipped with an overflow manhole that
drains into an existing curb inlet in Harvest Parkway. In the event that the system is full it will
backflow the incoming drainage pipe and fill the overflow manhole and be released into the
existing subdivision infrastructure. A copy of the C&H Stormwater Report for Phase & of
Flanders Mill is include din this submittal.
The following references were used in the preparation of this report:
a. COB Design Standards and Specifications Policy, 2004. Addendum #6
b. COB Modifications to Montana Public Works Standard Specifications (MPWSS)
A. Stormwater Infrastructure Calculations
The project area was divided into drainage areas as shown on Sheet SD 1.0 in Appendix A.
These drainage areas were used to determine the stormwater runoff flows, which in turn were
used to determine the required underground retention volume and storm drain pipe sizes.
Calculations are found in Appendix B. The underground system was designed to detain the
stormwater runoff from the 10-year storm event or the first 0.5 inch of rainfall over parking
impervious surfaces, whichever is greater. It was determined that the first half inch of runoff was
greater than the required detention volume, so the half inch runoff volume governed the design.
Flanders Mill Apartments Master Site Plan Stormwater Design Report
Page 1 of 2
B. Storm Drain Piping
The proposed storm drains that carry runoff into the underground retention system were sized to
carry the 25-year storm event peak runoff flow. It was determined that an arch reinforced
concrete pipe (RCP) 22 inches wide x 13 inches tall would suffice for Drainage Area 1 and a 15-
inch diameter PVC storm drain pipe is sufficient to carry the flows from Drainage Area 2.
Calculations are found in Appendix B.
C. Area Drain Grate Sizing
The area drain that receives runoff from the majority of the site was checked for capacity.
Assuming a water depth above the grate of 0.6 feet, the capacity of the selected 33-inch diameter
grate is 10.4 cfs, which exceeds the 25-year storm runoff tributary to that point of 9.3 cfs. With a
depth of 0.6 feet above the grate, the water surface elevation at the adjacent curb is kept below
0.15 feet below top back of curb. See Appendix C for more information.
D. Groundwater
Groundwater is an issue in this area of the City. We have bene monitoring the groundwater in 3
recently placed monitoring wells to determine the depth. Monitoring well #1 is located where
the proposed underground stormwater basin will be located. Between 4/30 and 5/20 4
measurement shave been taken and the results are shown in Appendix E. To date, the measured
groundwater depth in the monitoring well located in the proposed basin is 4723.8f. The bottom
of the proposed basin is retention 4724.25. Once the water and mains are installed adjacent to
the stormtech system the ground water will drop which is historical observed.
• Finish Grade Asphalt 4729.25
• Bottom of 18" pavement section 4727.75
• Top of infiltrators(6" gravel layer) 4727.25
• Bottom of infiltrator(30") 4724.75
• Bottom of porous stone (6") 4724.25
Appendices
A. Sheet SDI.0 (Drainage Area map)
B. Stormwater calculations
C. Area Drain grate sizing
D. Stormwater Maintenance Plan
E. Groundwater Monitoring Results
Flanders Mill Apartments Master Site Plan Stormwater Design Report
Page 2 of 2
Appendices
Appendix A — Sheet SD 1.0
SUMMARY TABLE
COLOR DRAINAGE CURB INLET OR 25-YR PEAK
AREA AREA DRAIN FLOW (CF)
_ 1 CURB INLET 1.0
2 AREA DRAIN 9.3
OVERFLOW \
MANHOLE R A av
CURB INLET
AND 15" PVC
AREA DRAIN AND
22"X13"ARCH RCP /
UNDERGROUND
R TANK SYSTEM -�
t �o
t f JI
L _ I,
' - w
SHEET
SD1.0
FLANDERS MILL APARTMENTS MADISON ENGINEERING
STORM WATER DRAINAGE EXHIBIT 995 TECHNOLOGY BLVDSUITE203
DRAINAGE AREA DELINEATION BO(406)N&.0252 16
(1061586-0262 w¢1r rx
01•rY Yr qt
BOZENIAN,NIT
no�:r ao®e
®aim ae w
Appendix B — Stormwater Calculations
Flanders MITI Apartments
Lot 1 Block 25 Phase 7 Flanders Mill Sub.
Stormwater Detention/Retention Calculations
Calculation of Required Volume for Storm Detention Pond
(Reference: Bozeman Stormwater Master Plan-1982)
Design Rainfall Freq. 10 year(see page III-5 of master plan)
IDF coefficient a 0.64
IDF coefficient b
IDF coefficient n 0.65
Pre-development Calculations Post-development Calculations
C C
Areas(ft): open space 397,970 0.20 Areas(ft): Landscaped 133.627 0.20
med.res. 0.35 Impervious 163.804 0.90
dense res. 0.50 Building 100.539 0.90
Total: 357 9 00 Total: 397,970
total area: 9.14 acres total area: 9.14 acres
composite C: 0.20 composite C: 0.66
Overland tc Overland t.
average slope: 1 25 percent average slope: 125 percent
travel distance: 950 feet travel distance: 900 feet
tc: 48 minutes tc: 23 minutes
Total tc: 48 minutes Total k: 23 minutes
intensity at tc(fig 23): 0.74 in/hr intensity at t�(fig 23): 1.21 in/hr
pre-devel peak runoff. 1.35 cfs post-devel peak runoff: 7.32 cfs
Storm Duration Intensity Future Runoff Runoff Release Required
(minutes) (in/hr) Rate(cfs) Volume(cf) Volume(cf) Storage(cf)
23 1.21 7.32 9954 1834 8120
25 1.14 6.93 10253 1996 8257
27 1.08 6.59 10537 2158 8379
29 1.03 6.29 10807 2320 8488
31 0.99 6.02 11065 2482 8584
33 0.95 5.77 11313 2643 8670
35 0.91 5.55 11551 2805 8745
37 0.88 5.36 11780 2967 8813
39 0.85 5.17 12001 3129 8872
41 0.82 5.01 12215 3291 8924
43 0.80 4.85 12422 3453 8969
45 0.78 4.71 12623 3615 9008
47 0.75 4.58 12818 3777 9041
49 0.73 4.46 13007 3939 9069
51 0.71 4.34 13192 4101 9091
53 0.70 4.23 13372 4262 9110
55 0.68 4.13 13548 4424 9123
57 0.66 4.04 13719 4586 9133
59 0.65 3.95 13887 4748 9139
61 0.64 3.86 14051 4910 9141
63 0.62 3.78 14211 5072 9139
65 0.61 3.70 14368 5234 9134
required detention storage(ft')
0.5"Rainfall Required Retention Calculations
Impervious Area
Pavement&Sidewalks 163.804 sf
Buildings 100.539 sf
Total Impervious 264,343 sf
Rainfall 0.5 inches
0.042 ft
Volume to be Retained 11,014 cf
Detention pond-ADS System.xls
Project: Flanders Mill Apartments `
Chamber Model- SC-740 StormTecfl
Units- Imperial I Chck Here ror Metric A division of IIItr1(f►/' ��
tunvrl.Jtt7.
Number of chambers- 126
Voids in the stone (porosity)- 40 %
Base of Stone Elevation- 10&00 ft
Amount of Stone Above Chambers- 6 in O Include Perhnetet Stone in Calculations
Amount of Stone Below Chambers- 6 in
Area of system- 4716 sf Min.Area- 4259 sf min. area
StormTech SC-740 Cumulative Storage Volumes
Height of Incremental Single Incremental Incremental Incremental Ch Cumulative
System Chamber Total Chamber Stone & St Chamber Elevation
(inches) (cubic feet) (cubic feet) (cubic feet) (cubic feet) (cubic feet) (feet)
42 0.00 0.00 157.20 157.20 10076 28 103.50
41 0.00 0.00 157.20 157.20 9919.08 103.42
40 0.00 0.00 157.20 157.20 9761.88 103.33
39 0.00 0.00 157.20 157.20 9604.68 103.25
38 0.00 0.00 157.20 157.20 9447.48 103.17
37 0.00 0.00 157.20 157.20 9290.28 103.08
36 0.05 6.93 154.43 161.36 9133.08 103.00
35 0.16 20.53 148.99 169.52 8971.73 102.92
34 0.28 35.52 142.99 178.51 8802.21 102.83
33 0.60 76.10 126.76 202.86 8623.69 102.75
32 0.80 101.02 116.79 217.81 8420.83 102.67
31 0.95 119.78 109.29 229.07 8203.03 102.58
30 1.07 135.39 103.04 238.43 7973.95 102.50
29 1.18 148.74 97.70 246.45 7735.52 102.42
28 1.27 159.47 93.41 252.88 7489.08 102.33
27 1.36 170.73 88.91 259.64 7236.19 102.25
26 1.45 183.22 83.91 267.13 6976.55 102.17
25 1.52 192.12 80.35 272.47 6709.42 102.08
24 1.58 199.37 77.45 276.82 6436.95 102.00
23 1.64 206.93 74.43 281.36 6160.13 101.92
22 1.70 214.14 71.54 285.68 5878.77 101.83
21 1.75 220.87 68.85 289.72 5593.09 101.75
20 1.80 227.15 66.34 293.49 5303.37 101.67
19 1.85 233.73 63.71 297.44 5009.88 101.58
18 1.89 238.53 61.79 300.32 4712.44 101.50
17 1.93 243.68 59.73 303.41 4412.12 101.42
16 1.97 248.85 57.66 306.51 4108.71 101.33
15 2.01 253.25 55.90 309.15 3802.20 101.25
14 2.04 257.67 54.13 311.80 3493.05 101.17
13 2.07 261.45 52.62 314.07 3181.25 101.08
12 2.10 265.22 51.11 316.33 2867.18 101.00
11 2.13 268.61 49.76 318.36 2550.85 100.92
10 2.15 271.39 48.65 320.03 2232.49 100.83
9 2.18 274.31 47.48 321.79 1912.46 100.75
8 2.20 276.99 46.40 323.40 1590.67 100.67
7 2.21 278.12 45.95 324.07 1267.27 100.58
6 0.00 0.00 157.20 157.20 943.20 100.50
5 0.00 0.00 157.20 157.20 786.00 100.42
4 0.00 0.00 157.20 157.20 628.80 100.33
Flanders Mill Apartments,Lot 1,Block 25 Appendix B
Peak flow calculations
Curb inlet Drainage Areas-Post Development
See SD1.0 for visual reference
Peak Flow Summary(cfs)
Drainage Area No. Area(Ac.) Weighted C 100 Yr 25 Yr 10 Yr
1 8.657 0.66 15.4 9.3 6.9
2 0.479 0.66 1.8 1.0 0.8
OF Equations from Bozeman Stormwater Master Plan for City of Bozeman,March 1982
General Equation: i=a/(b+D)"where D is duration in hours,i=intensity in inches/hour
Storm Information
Design Rainfall Freq. 100 25 10
OF coefficient a 1.01 0.78 0.64
OF coefficient b 0 0 0
OF coefficient n 0.67 0.64 0.65
Adjustment Factor Cf: 1.25 1.1 1
Weighted C Value-Entire site
Landscaped 133.627 0.20
Impervious 163.804 0.90
Building 100.539 0.90
397,970
Composite C 0.66
Peak Q values
Drainage Area 1
Area 8.66 acres
Weighted C 0.66
Average slope 1.25 percent
Travel Distance 900 feet
Design Rainfall Freq. 100 25 10 years
C*Cf 0.83 0.73 0.66 (Shall not exceed 1.00)
Total t�: 14.00 19.19 22.66 minutes
intensity at tc 2.68 1.62 1.21 in/hr
peak runoff: 15.4 9.3 6.9 cfs
Drainage Area 2
Total 0.479 acres
Weighted C 0.66
Average slope 1.00 percent
Travel Distance 89 feet
Design Rainfall Freq. 100 25 10 years
C*Cf 0.83 0.73 0.66 (Shall not exceed 1.00)
Total t�: 4.74 6.50 7.67 minutes
intensity at t. 5.53 3.23 2.44 in/hr
peak runoff: 1.8 1.0 0.8 cfs
Page 1 of 7
151.PVC Appendix B
Checked at slope=0.36%
CIRCULAR CHANNEL
T
Manning's Eqn. Q=1.486 A RzJ S'n
n
Diameter,do(in)= 15 4-Enter Value
Diameter,do(ft)= 1.25
THETA
Units= 1.486
n= 0.013
Slope,S(ft/ft) 0.0036
Wetted Hydraulic Hydraulic Sertion tnergy,
Area,A Perimeter,P Radius,R Top Width,T Depth,D Factor,Z Q(gpd.8 =V2/2g
Depth,y(ft) Theta(red) (ft) (ft) (ft) 00 (ft) (it') Q(cis) Q(gpm) hour day) V(ft/s) (ft)
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00
0.06 0.90 0.02 0.56 0.04 0.54 0.04 0.00 0.0 8.4 4009.5 0.8 0.01
0.13 1.29 0.06 0.80 0.08 0.75 0.09 0.02 0.1 36.3 17432.1 1.3 0.02
0.19 1.59 0.12 0.99 0.12 0.89 0.13 0.04 0.2 84.6 40586.7 1.6 0.04
0.25 1.85 0.17 1.16 0.15 1.00 0.17 0.07 0.3 152.3 73118.3 1.9 0.06
0.31 2.09 0.24 1.31 0.18 1.08 0.22 0.11 0.5 238,3 114373.9 2.2 0.08
0.38 2.32 0.31 1.45 0.21 1.15 0.27 0.16 0.6 340.6 163510.6 2.5 0.09
0." 2.53 0.38 1.58 0.24 1.19 0.32 0.22 1.0 457.4 219543.4 2.7 0.11
0.60 2.74 0.46 1.71 0.27 1.22 0.37 0.28 1.3 586.2 281370.3 2.8 0.13
0.56 2.94 0.54 1.84 0.29 1.24 0.43 0.35 1.6 724.6 347784.3 3.0 0.14
0.63 3.14 0.61 1.96 0.31 1.25 0.49 0.43 1.9 869.7 417478.4 3.2 0.15
0.69 3.34 0.69 2.09 0.33 1.24 0.56 0.52 2.3 1018.8 489043.4 3.3 0.17
0.75 3.54 0.77 2.22 0.36 1.22 0.63 0.61 2.6 1168.7 560957.6 3.4 0.18
0.81 3.75 0.84 2.34 0.36 1.19 0.71 0.71 2.9 1315.8 631568.4 3.5 0.19
0.88 3.96 0.92 2.48 0.37 1.15 0.80 0.82 3.2 1456.4 699057.3 3.5 0.19
0.94 4.19 0.99 2.62 0.38 1.08 0.91 0.94 3.5 1586.2 761378.5 3.6 0.20
1.00 4.43 1.05 2.77 0.36 1.00 1.05 1.08 3.8 1700.3 816142.7 3.6 0.20
1.06 4.69 1.11 2.93 0.38 0.89 1.25 1.24 4.0 1792.4 860373.3 3.6 0.20
1.13 5.00 1.16 3.12 0.37 0.75 1.55 1.45 4.1 1853.9 889894.8 3.6 0.20
1.19 5.38 1.20 3.36 0.36 0.64 2.21 1.79 4.2 1869.1 897173.3 3.5 0.19
1.25 6.28 1.23 3.93 0.31 O,On 3,9 1740.1 835239.2 3.2 0.16
4.5
4.0
3.5
30
0(CFS) 2.5 / I
♦
-E(ft) 2.0 /
♦
1.5
♦
05 -
00
0.00 020 0.40 060 080 1.00 1 20 1.40
Depth(ft)
18"PVC/concrete Appendix B
Checked at slope 0.7%
CIRCULAR CHANNEL
T
Manning's Eqn. Q= 1.486 A Rw S112
n
Diameter,do(in)= 18 44-Enter Value
Diameter,do(ft)= 1.5
THETA
Units= 1.486
n= 0.013
Slope,S(ft/ft) 0.007
Wetted Hydraulic 'Section triergy,
Area,A Perimeter,P Radius,R Top Width,T Hydraulic Factor,Z Q(gpd-8 =V2/2g
Depth,y(ft) Theta(red) (ft') (ft) (ft) (ft) Depth,D(ft) (ft 512) Q(cfs) Q(gpm) hour day) V(ft/s) (ft)
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00
0.08 0.90 0.03 0.66 0.05 0.65 0.05 0.01 0.0 16.9 9091.7 1.3 0.03
0.15 1.29 0.09 0.97 0.10 0.90 0.10 0.03 0.2 82.3 39527.3 2.0 0.06
0.23 1.59 0.17 1.19 0.14 1.07 0.16 0.07 0.4 191.7 92030.5 2.6 0.10
0.30 1.85 0.25 1.39 0.18 1.20 0.21 0.12 0.8 345.4 165795.9 3.1 0.15
0.38 2.09 0.35 1.57 0.22 1.30 0.27 0.18 1.2 540.3 259343.1 3.5 0.19
0.45 2.32 0.45 1.74 0.26 1.37 0.32 0.25 1.7 772.4 370760.7 3.9 0.23
0.53 2.53 0.55 1.90 0.29 1.43 0.39 0.34 2.3 1037.1 4978115.3 4.2 0.27
0.60 2.74 0.66 2.05 0.32 1.47 0.45 0.44 3.0 1329.2 6360077 4.5 0.31
0.68 2.94 0.77 2.21 0.35 1.49 0.52 0.55 3.7 1642.9 788601.6 4.7 0.35
0.75 3.14 0.88 2.36 0.38 1.50 0.59 0.66 4.4 1972.2 946633.4 5.0 0.38
0.83 3.34 1.00 2.51 0.40 1.49 0.67 0.81 5.1 2310.2 1108907.0 5.2 0.41
0.90 3.64 1.11 2.66 0.42 1.47 0.75 0.96 5.9 2649.9 1271972.7 5.3 0.44
0.98 3.75 1.22 2.81 0.43 1.43 0.85 1.12 6.6 2983.5 1432082.9 5.5 0.46
1.05 3.96 1.32 2.97 0.44 1.37 0.96 1.30 7.4 3302.3 1585114.2 5.6 0.48
1.13 4.19 1.42 3.14 0.45 1.30 1.09 1.49 8.0 3596.7 1726427.7 5.6 0.49
1.20 4.43 1.52 3.32 0.46 1.20 1.26 1.70 8.6 3855.4 1850605.5 5.7 0.50
1.28 4.69 1.60 3.52 0.45 1.07 1.49 1.96 r!9A
4064.4 1950898.6 5.7 0.50
1.35 5.00 1.68 3.75 0.45 0.90 1.86 2.29 4203.8 2017838.7 5.6 0.49
1.43 5.38 1.73 4.04 0.43 0.65 2.65 2.82 4238.2 20343427 5.4 0.46
1.50 6.28 1.77 4.71 0.38 0.00 3945.6 1893906.91 5.0 1 0.38
10.0
9.0
8.0
7.0 �-
i
lCFS)
6.0
I �
V(Ms)
5.0 �
-E(ft)
4.0
I
3.0 000, '
i
2.0 1000,
1.0
0.0
0.00 0.20 0.40 0.60 080 1.00 1.20 1.40 1.60
Depth(ft)
1/27/2020 concretesipe_sizes I SD&W
ARCH PIPES:
Pipc Size (in.) Round Equiv. Metric Equivalent(mm) Area(I'tQ) Weight(lbs/t't) Wall Thickness
18x11 15 460x280 1.1 188 IF 3
22x 13 18 560x245 1.6 233 3 1/8
29x18 24 725x460 2.9 325 j 3'/2
36x23 30 920x570 4.4 392 j 3'/z
44x27 36 1110x675 6.5 537 4
51x31 42 1300x795 8.7 696 4%Z
58x36 48 1485x915 11.4 885 5
65x40 54 1650x1015 14.3 1,079 5'/Z
73x45 60 1855x1145 17.7 1,333 6
88x54 72 2235xl370 25.6j 1,856 j 7
www.sd-w.com/channel—fiDw/concrete_pipe—sizes/ 1/1
Appendix C — Area Drain Grate Sizing
■ Note:Whan specifying/ordering grates,refer to"Choosing the Proper Inlot Grate"on pages 125-126.
For a complete listing of FREE OPEN AREAS and WEIR PERIMETERS of all NEENAH grates,referto pages 327-332.
R•4370 Series
Round Drainage Grate
Heavy Duty
A WEIR
SO. PERIMETER �� m
CATALOG ORATE FT. LINEAL
NUMBER TYPE OPEN FEET
R4T101 C D.1 1.7
R431(1-2 G U 25
Ri910.3 _ E CA 99
RAI3744 G CA 39 PAR 011MV.1
na370-5 G u 4.7
R-4310.8 G 01B 5.1
R471&7 G 1)1 52 g7ustrating R-4370.12
R—M&B 12 55
R4310-9 13 5B
11431610 A 1.1 52
R-r310-12 r 09 sB
11-M13 G J3— 5B
R-4310,15 D ID 53
R-1370.17 D ID BD
R-4370.18 E IS 8D
R431a21 D 1)9 An
R471D92 D 1.1 BD
R4910.23 H 0.9 63
R-4310.25 6 112 73
R437&28 G 23 as
R-WQ-27A G 24 as
MDst grates listed can be furnished with cast iron angleframe when specked.
Frame is of 112"metal
Dimensions in inches
Catalog No. A a G H Type
R-4370.1 G 3/8 1 1/4 1 x 1 1/2 C
R-4370-2 9 1/2 2 112 1 112 x 3112 5/8 G
R-4370-3 15 1 1/4 1 x 121/4 1 E
R-4370.4 15 1 1/4 3/4 x 21/4 3/4 G
R-4370.5 18 1 112 4 x Fj 11 1 114 G 1 FOo4wva
_ R-4370•6' 19 111 1 1/'J 3/4 x 5 1/4 319 G
R-4370.7 20 1 3/3 2 x 2 1 G
R-4370-8 21 1 1/4 3/4 x 19 112 3/4 E aQ.
R-4370-9 22 11/2 11/4 1 C
R-4370-10 22 1 1/2 1 1/4 I §A
R-4370.12 22 1 1/2 1 3/8 x 5 1 F
R-4370.13` 22 1 112 2 x 6 1 114 G
R-4370-15" 22 1/2 1 3/4 1 1/11 1 D
R-4370-17 22 3/4 1 3/4 1 112 1 D
R-4370.18 22 3/4 1 3/4 1 1/2 718 E
R-4370.21 23 1 1/2 1 1/4 1 D
R-4370-22"" 23 1 3/4 1 1 116 D
R-4370-23 24 1 112 2 1/4 x 2 114 1 112 H
R-4370.25 29 3 3/4 1 G
R-4370-26 33 2 1 112 1 G
R-4370-27A 38 1112 1 1 G
Light Duty.
••Frame not available.
§Alternate Type 6 or Type C grates available.
Alternate Type G grate available.
1 NEENAH FOUNDRY
CLICK HERE to return to the Table of Contents
0
r ,10
I
I °o
cC
it
- _ 41
! a°
IL
'C -
o �
a177
- -- - - -- -— —j - - -
— - 0r
I 4—F
aCL S
p
JL
co
- --- - -- — - ( s
• —! -- i g�'16 8n 3
—{— — - - - - - - Z 8
cc
O
W� ;--
o
Z LL
0 0 0 0 0
0 0 0 T O 0
N N 0 O O � O f F E
src`N�
(SIO) o4ou mou lolul GIRJE)
Appendix D — Stormwater Maintenance
Plan
STORMWATER MAINTENANCE PLAN
Flanders Mill Apartments
Owner's responsibility for routine inspection and maintenance
1. Keep the inlets of the facilities free of leaves, rocks, and other debris.
2. Re-sod damaged or maintained areas immediately, or use grass plugs from the
adjacent up-slope area.
3. See that litter and other debris are removed from inlets, swales, and vegetated and
paved areas.
4. Maintenance of the underground systems are as follows:
• Minimum required maintenance includes a quarterly inspection during the
first year of operation and a yearly inspection thereafter. Utilize inspection
ports for inspections.
• The inspection ports can be used to pump water into the system and re-
suspend accumulated sediment so that is may be pumped out. Flush and
pump as inspections deem necessary.
• Utilize the adjacent upstream storm sewer manhole for removal (vacuuming)
of debris from the end of the storm drain at the connection point with the
underground chamber.
5. Owner to maintain and fund Operation and Maintenance of stormwater facilities.
Jesse Chase, Owner
G:\MADISON ENGINEERING\PROJECTS\2017\17-128 Flanders Mill\Storm\STORMWATER MAINTENANCE PLAN.doc
StormTeche
Detention oRecharge
Subsurface • .•-
��� `; yam,• 1'. i •, -
r..
i
Isolator"' Row
k
Y... y.
♦ M Manual
•rmTech' Chamber System for • Management
1.0 The Is olatorT" Row
1.1 INTRODUCTION The Isolator Row is typically designed to capture the
An important component of any Stormwater Pollution "first flush" and offers the versatility to be sized on a vol-
Prevention Plan is inspection and maintenance.The ume basis or flow rate basis.An upstream manhole not
StormTech Isolator Row is a patent pending technique only provides access to the Isolator Row but typically
to inexpensively enhance Total Suspended Solids (TSS) includes a high flow weir such that storm water flowrates
removal and provide easy access for inspection and or volumes that exceed the capacity of the Isolator Row
maintenance. overtop the over flow weir and discharge through a
manifold to the other chambers.
The Isolator Row may also be part of a treatment train.
By treating storm water prior to entry into the chamber
system, the service life can be extended and pollutants
such as hydrocarbons can be captured. Pre-treatment
best management practices can be as simple as deep
sump catch basins,oil-water separators or can be inno-
vative storm water treatment devices.The design of
the treatment train and selection of pretreatment devices
by the design engineer is often driven by regulatory
requirements.Whether pretreatment is used or not,the
Isolator Row is recommended by StormTech as an
effective means to minimize maintenance requirements
and maintenance costs.
Note:See the StormTech Design Manual for detailed
Looking down the Isolator Row from the manhole opening,woven information on designing inlets for a StormTech system,
geotextile is shown between the chamber and stone base. including the Isolator Row.
1.2 THE ISOLATOR'ROW StormTech Isolator Row with Overflow Spillway
The Isolator Row is a row of StormTech chambers,either (not to scale)
SC-740 or SC-310 models,that is surrounded with filter OPTIONAL
fabric and connected to a closely located manhole for PRE-TREATMENT
easy access.The fabric-wrapped chambers provide for
settling and filtration of sediment as storm water rises in STORMTECH
the Isolator Row and ultimately passes through the filter ISOLATOR ROW
fabric.The open bottom chambers and perforated side-
walls allow storm water to flow both vertically and horizon-
tally out of the chambers. Sediments are captured in the
Isolator Row protecting the storage areas of the adja- MANHOLE
cent stone and chambers from sediment accumulation. OVERFLOW
WEIR
Two different fabrics are used for the Isolator Row.A
woven geotextile fabric is placed between the stone
and the Isolator Row chambers.The tough geotextile
provides a media for storm water filtration and provides ECCENTRIC
a durable surface for maintenance operations. It is also HEADER
designed to prevent scour of the underlying stone and
remain intact during high pressure jetting.A non-woven
fabric is placed over the chambers to provide a filter
media for flows passing through the perforations in the
sidewall of the chamber.
OPTIONAL ACCESS STORMTECH CHAMBERS
2 Call StormTech at 888.892.2694 or visit our website at www.stormtech.com for technical and product information.
2.0 Isolator Row Ins pection/Maintenance StormTech"
2.1 INSPECTION
The frequency of Inspection and Maintenance varies -
by location.A routine inspection schedule needs to be
established for each individual location based upon site - f
specific variables. The type of land use (i.e. industrial,
commercial residential),anticipated pollutant load, per-
cent imperviousness, climate,etc. all play a critical role
in determining the actual frequency of inspection and
maintenance practices.
At a minimum, StormTech recommends annual inspec-
tions. Initially, the Isolator Row should be inspected every
6 months for the first year of operation. For subsequent
years,the inspection should be adjusted based upon
previous observation of sediment deposition.
The Isolator Row incorporates a combination of standard
manhole(s)and strategically located inspection ports
(as needed).The inspection ports allow for easy access Examples of culvert cleaning nozzles appropriate for Isolator Row
to the system from the surface,eliminating the need to maintenance.(These are not StormTech products.)
perform a confined space entry for inspection purposes.
Maintenance is accomplished with the JetVac process.
If upon visual inspection it is found that sediment has The JetVac process utilizes a high pressure water noz-
accumulated,a stadia rod should be inserted to deter- zle to propel itself down the Isolator Row while scouring
mine the depth of sediment. When the average depth and suspending sediments.As the nozzle is retrieved,
of sediment exceeds 3 inches throughout the length of the captured pollutants are flushed back into the man-
the Isolator Row, clean-out should be performed. hole for vacuuming. Most sewer and pipe maintenance
companies have vacuum/JetVac combination vehicles.
2.2 MAINTMANCE Selection of an appropriate JetVac nozzle will improve
The Isolator Row was designed to reduce the cost of maintenance efficiency. Fixed nozzles designed for cul-
periodic maintenance. By"isolating" sediments to just verts or large diameter pipe cleaning are preferable.
one row, costs are dramatically reduced by eliminating Rear facing jets with an effective spread of at least 45"
the need to clean out each row of the entire storage are best. Most JetVac reels have 400 feet of hose allow-
bed. If inspection indicates the potential need for main- ing maintenance of an Isolator Row up to 50 chambers
tenance, access is provided via a manhole(s)located long.The JetVac process shall only be performed on
on the end(s)of the row for cleanout. If entry into the StormTech Isolator Rows that have AASHTO class 1
manhole is required, please follow local and OSHA rules woven geotextile(as specified by StormTech)over
for a confined space entries. their angular base stone.
StormTech Isolator Row(not to scale)
COVER ENTIRE ROW WITH AASHTO M288
1 2"MIN ID 25"MAX OD PIPE INSPECTION PORT- CLASS 2 NON-WOVEN GEOTEXTILE
SET 1.5"FROM BOTTOM LOCATION PER SC-740—B'WIDE STRIP _STORM TECH
OF CHAMBER ENGINEER'S DRAWING SC-310—T WIDE STRIP f ENDCAP
CATCH
BASIN
OR
ANHIO
,4,i� ,y5 V.
vp I
- 6"1.......
2FT MIN. _ I IF
r
SU P - WOVEN GEOTEXTILE THAT MEETS AASHTO M288 CLASS 1
REQUIREMENTS,BETWEEN STONE BASE AND CHAMBERS
SC-740-5'-6'WIDE STRIP
SC-310-4'WIDE STRIP
Call StormTech at 888.892.2694 or visit our website at www.stormtech.com for technical and product information. 3
3 .0 Isolator Row Step By Step Maintenance Procedures
Step 1) Inspect Isolator Row for sediment StormTech Isolator Row(not to scale)
A)Inspection ports(if present)
11 ej- AI
i. Remove lid from floor box frame �2 ;�)
ii. Remove cap from inspection riser
iii. Using a flashlight and stadia rod,
measure depth of sediment and J1
record results on maintenance log.
iv. If sediment is at, or above, 3 inch
depth proceed to Step 2. If not 4
proceed to step 3.
B)All Isolator Rows
i. Remove cover from manhole at
upstream end of Isolator Row
ii. Using a flashlight, inspect down Isolator Row through outlet pipe
1.Mirrors on poles or cameras may be used to avoid a confined space entry
2.Follow OSHA regulations for confined space entry if entering manhole
iii. If sediment is at or above the lower row of sidewall holes(approximately 3 inches)proceed to Step 2.
If not proceed to Step 3.
Step 2)Clean out Isolator Row using the JetVac process
A)A fixed culvert cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable
B)Apply multiple passes of JetVac until backflush water is clean
C)Vacuum manhole sump as required
Step 3)Replace all caps,lids and covers, record observations and actions
Step 4)Inspect&clean catch basins and manholes upstream of the StormTech system
Sample Maintenance Log
•..
Sediment
. .. point Depth Observations!Actions Inspectoi
to ch
Otto
131/b/O 1 6.3 ft. none New inst allat ion.Bed pant is Cl frame at grade dim
24/01 62 0.1ft. Some grit felt sm
6/20/03 5.8 0.5 ft. Micky fed,debris visible in manhole and in ry
Isolator rook maintenance due
717103 6.3ft. 0 System jet tad and%ecuned djm
0
StormIT:eCcft"
Detention•Retention•Recharge
Subsurface Stormwater Management'
20 Beaver Road,Suite 104 Wethersfield Connecticut 06109
860.529.8188 888.892.2694 fax 866.328.8401 www.stormtech.com
StormTech products are covered by one or more of the following patents: U.S.Patents:5,401,459;5,511,903;5,716,163;5.588,778;5,839,844;
Canadian Patents:2,158,418 Other U.S.and Foreign Patents Pendinfrinted in U.S.A.
0 Copyright.All rights reserved.StormTech LLC,2004 S090104-1
Appendix E - Groundwater Monitoring
3 0o M M
N
O
N
O
N �
kn 00 110 �10
N
3 M O� M
O C7 N r- r-
O
N
k b
N
kn N O
N
�,6 tt�
3 M
M 01 M
rn
N
0000 O
'n O N
N
�,O �,O V1
O M O`
O C7 N N M
O
N
O
M y
O N
O �
> M 't N
cd N N 00 M l-
E+ Lij N M M
on
p � N
O. C
fi a •° "q 0000
O O > oM M 06
H
on
° N M
F3
O