Transcript No Slide Title

Wastewater Storage Pond
Design
Prepared by J.E. Andrews, PE, NRCS - Lakewood, CO
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Workshop Objectives
• Assemble some basic design data
• Estimate pond size required
• Develop a preliminary cost estimate
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Consult with a knowledgeable Engineer to:
• Consider other options and alternatives
• Evaluate pond site location(s) & lining requirements
• Analyze technical requirements for
•
•
•
•
storage period and pump needs
solids trap and snow removal
hydrologic & waste loading factors
need for treatment
• Design inlet, outlet & other related facilities
• Prepare construction drawings & specs
• Perform construction inspection
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Design Considerations
 Location
 Site Options and Constraints
 Plans and Options for Future Expansion
 Soil Options and Constraints (clay borrow or liner)
 Surface or Groundwater Concerns and Constraints
 Volume - needs to facilitate the utilization plan
 How will the liquids & sludge be removed and used?
 How often will (or can) the pond be emptied?
 What is your concern level for odor control?
 What is your concern level for nutrient conservation?
 Features (shape, depth, side slope, inlet/outlet type, etc.)
 Operation & Maintenance Options and Requirements
 THINK SAFETY, SAFETY, SAFETY !!!
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Cross Section of a Waste Storage Pond
Top Width - 8' to 16'
Overflow Pipe or Spillway
Outside Slope
3:1 or flatter
(wh en n eed ed )
freeboard - 2 ft. min.
Start Pum ping Level
25 year Storm Runoff
Normal Contaminated Runoff
Working Storage
Liner for
Seepage Control
+ Precipitation - Evaporation On Pond Surface
W aste Storage
manure, waste water,
waste feed & bedding
Inside slope 3:1
accumulated solids
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Information Needed for Estimating Pond Volume
• Storage Period
• Size of Runoff Producing Areas
• Roofs, Paved Lots & Unpaved Lots
• Areas for future expansion
• Other Areas
• Climate Data for site location (including evaporation)
• Volume of manure, wastewater & other by products
to be stored in the pond.
• Worksheet #8 &Tables 8a, 8b & 8c
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Example - Frank’s Dairy
• Located near Fort Morgan, Colorado
• Pond effluent can be applied May through September
• 5 acres of earthen feedlot & solid manure stacking area
• 2,000 sq. ft. concrete surfaced holding area
• 1,000 sq. ft. of roofs that drain across the concrete lot
• 2,000 gal. wastewater per day from the milking center
• Manure & other solids are kept out of the pond
• No plans for expansion at this site
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Step 1 - Get Climate Data
Table 8a. COLORADO CLIMATE DATA FOR WASTE MANAGEMENT SYSTEM DESIGN
Runoff as % of Annual Rainfall 3
Average Annual Annual FWS Paved Feedlot Earth Feedlot 25 yr - 24 hr
Precipitation1 Evaporation2
CN= 97
CN=90
Precipitaion4
County
Climate Station
(inches)
(inches)
(% of annual) (% of annual)
(inches)
Montrose
Cimmaron 3S
13.1
40
30%
10%
2.0
Montrose
Uravan
12.9
45
30%
10%
2.2
Morgan
Fort Morgan
12.7
48
43%
15%
3.4
Morgan
Wiggins 7SW
16.1
47
43%
15%
3.4
Otero
La Junta
15.7
55
45%
16%
4.0
Otero
Rocky Ford 2SE
11.7
54
45%
16%
4.0
@ Fort Morgan Climate Station
Annual Rainfall = 12.7”
43% runs off paved areas
15% runs off earthen feedlots
25yr-24hr Rainfall = 3.4”
Average Lake Evaporation = 48”
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Worksheet 8. Waste Storage Pond Volume Determination
Facility Name:
Frank's Dairy
Prepared by: JEA
Location: Fort Morgan, CO
date: Dec-00
Checked by:
Runoff Volume Computations
Average Annual Rainfall:
Roofed Area (CN = 100)
Runoff
(
Paved Area (CN = 97)
Runoff
(
Annual Runoff %:
Annual Runoff %:
15
inches
25 year-24 hour Rainfall:
+
Annual
Rainfall
43
Earthen Area (CN = 90 )
Runoff
12.7
+
inches
/ 12 =
) x
25yr-24hr
Rainfall
3.4
Roof Area
(sq. ft.)
Runoff Volume
(cubic feet)
/ 12 =
) x
Annual
25yr-24hr
Area
Runoff Volume
Runoff
Runoff
(sq. ft.)
(cubic feet)
+
(
) x
x 3,630 =
Annual
25yr-24hr
Area
Runoff Volume
Runoff
Runoff
(acres)
(cubic feet)
Design Runoff Volume =
(cubic feet)
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Step 2 - Calculate Roof Runoff Volume
Worksheet 8. Waste Storage Pond Volume Determination
Facility Name:
Frank's Dairy
Location: Fort Morgan
Prepared by: JEA
date: Dec-00
Checked by:
Runoff Volume Computations
Average Annual Rainfall:
12.7
(
12.7
Roofed Area (CN = 100)
Runoff
inches
Annual
Rainfall
Section 8 - Wastewater Storage Pond Design
+
25 year-24 hour Rainfall:
3.4
25yr-24hr
Rainfall
) x
1,000
Roof Area
(sq. ft.)
3.4
inches
/ 12 =
1,342
Runoff Volume
(cubic feet)
Colorado CNMP Workshop
Step 3 - Calculate Paved Area Runoff Volume
Worksheet 8. Waste Storage Pond Volume Determination
Facility Name:
Frank's Dairy
Prepared by: JEA
Location: Fort Morgan
date: Dec-00
Checked by:
Runoff Volume Computations
Average Annual Rainfall:
12.7
inches
(
5.5
* +
Paved Area (CN = 97)
Runoff
Annual Runoff %:
43
25 year-24 hour Rainfall:
3.06
**) x 2,000
3.4
inches
/ 12 = 1,420
Annual
25yr-24hr
Area
Runoff Volume
Runoff
Runoff
(sq. ft.)
(cubic feet)
* Annual Runoff = Annual Runoff % x Annual Rainfall 100
** Find 25yr-24hr runoff from 3.4” rain in Table 8b.
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Finding runoff depth from a 3.4” rain
on a concrete feedlot using Table 8b.
Runoff for Paved Surface Feedlots, Curve Number:
Inches
0.0
1.0
2.0
3.0
4.0
5.0
tenths\
97
6.0
0
0.02
0.71
1.67
2.66
3.65
4.65
5.64
0.1
0.00
0.80
1.77
2.76
3.75
4.75
5.74
0.2
0.04
0.89
1.87
2.86
3.85
4.85
5.84
0.3
0.10
0.99
1.97
2.96
3.95
4.95
5.94
0.4
0.18
1.09
2.06
3.06
4.05
5.05
6.04
0.5
0.26
1.18
2.16
3.15
4.15
5.15
6.14
0.6
0.34
1.28
2.26
3.25
4.25
5.25
6.24
0.7
0.43
1.38
2.36
3.35
4.35
5.34
6.34
0.8
0.52
1.48
2.46
3.45
4.45
5.44
6.44
0.9
0.61
1.57
2.56
3.55
4.55
5.54
6.54
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Step 4 - Calculate Earthen Area Runoff Volume
Worksheet 8. Waste Storage Pond Volume Determination
Facility Name:
Frank's Dairy
Prepared by: jea
Location: Fort Morgan, CO
date: Dec-00
Checked by:
Runoff Volume Computations
Average Annual Rainfall:
Earthen Area (CN = 90 )
Runoff
Annual Runoff %:
15
(
12.7
inches
1.9
* +
25 year-24 hour Rainfall:
2.36
**) x
5.00
3.4
inches
x 3,630 = 77,359
Annual
25yr-24hr
Area
Runoff Volume
Runoff
Runoff
(acres)
(cubic feet)
* Annual Runoff = Annual Runoff % x Annual Rainfall 100
** Find 25yr-24hr runoff from 3.4” rain in Table 8b.
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Finding runoff depth from a 3.4” rain
on a earth surfaced feedlot using
Table 8b.
(include areas outside the feedlot too)
Runoff for Earth Surfaced Feedlots, Curve Number:
90
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0
0.06
0.32
1.09
1.98
2.92
3.88
4.85
0.1
0.02
0.39
1.18
2.08
3.01
3.97
4.94
0.2
0.00
0.46
1.27
2.17
3.11
4.07
5.04
0.3
0.01
0.53
1.35
2.26
3.20
4.17
5.14
0.4
0.02
0.61
1.44
2.35
3.30
4.26
5.24
0.5
0.06
0.68
1.53
2.45
3.40
4.36
5.33
0.6
0.10
0.76
1.62
2.54
3.49
4.46
5.43
0.7
0.14
0.84
1.71
2.64
3.59
4.55
5.53
0.8
0.20
0.93
1.80
2.73
3.68
4.65
5.63
0.9
0.26
1.01
1.89
2.82
3.78
4.75
5.73
tenths\
Section 8 - Wastewater Storage Pond Design
Inches
Colorado CNMP Workshop
Step 5 - Total Runoff Volumes
Worksheet 8. Waste Storage Pond Volume Determination
Facility Name:
Frank's Dairy
Prepared by: JEA
Location: Fort Morgan, CO
date: Dec-00
Checked by:
Runoff Volume Computations
Average Annual Rainfall:
12.7
Roofed Area (CN = 100)
Runoff
(
12.7
Paved Area (CN = 97)
Runoff
(
Annual Runoff %:
Annual Runoff %:
15
+
Annual
Rainfall
43
Earthen Area (CN = 90 )
Runoff
inches
5.5
25 year-24 hour Rainfall:
3.4
) x
25yr-24hr
Rainfall
+
3.06
1,000
Roof Area
(sq. ft.)
) x
2,000
3.4
inches
/ 12 = 1,342
Runoff Volume
(cubic feet)
/ 12 = 1,420
Annual
25yr-24hr
Area
Runoff Volume
Runoff
Runoff
(sq. ft.)
(cubic feet)
(
1.9
Annual
Runoff
+
2.36
) x
5.00
x 3,630 = 77,359
25yr-24hr
Area
Runoff Volume
Runoff
(acres)
(cubic feet)
Design Runoff Volume =
80,120
(cubic feet)
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Step 6 - Calculate Design Volume
Storage Volume Computations
Design Runoff Volume, in cubic feet:
(from calculations above)
Manure Solids Volume, in cubic feet:
(Multiply tons/year by 50 cu. ft./ton)
Other Solids Volume, in cubic feet:
Liquid Manure Volume, in cubic feet:
(Divide gal/year by 7.5 gal/cu. ft.)
Process Wastewater Volume, in cubic feet:
(Divide gal/year by 7.5 gal/cu. ft.)
Total Volume Required, in cubic feet:
* Process Wastewater Volume = 2,000 gal/day x 365 days/year / 7.5gal/cu. ft. = 97,333 cu. ft.
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Step 7 - Choose Pond Dimensions
•
Choose a depth between 6’ & 12’
• As deep as possible within site limits
• Pond bottom should be 4’ above the water table
•
From Table 8c, select a length & width,
such that:
• Fits available space
• Selected volume is greater than design volume
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Use Table 8c - for a given depth choose a width & length
that results in a volume greater than 177,453 cu ft.
Assume an 8 foot depth for Frank’s Dairy
Table 8c. Volume of Retangular Ponds for given width, length & depth
Foot Depth
3 : 1 Inside Slope
75
100
125
150
175
200
225
250
275
60
75
100
125
11,904
16,224
23,424
30,624
37,824
45,024
52,224
59,424
66,624
73,824
16,224
22,344
32,544
42,744
52,944
63,144
73,344
83,544
93,744
103,944
23,424
32,544
47,744
62,944
78,144
93,344
108,544
123,744
138,944
154,144
30,624
42,744
62,944
83,144 103,344
123,544
143,744
163,944
184,144
204,344
150
37,824
52,944
78,144 103,344 128,544
153,744
178,944
204,144
229,344
254,544
175
45,024
63,144
93,344 123,544 153,744
183,944
214,144
244,344
274,544
304,744
200 52,224 73,344
225 59,424 83,544
250 66,624 93,744
275 73,824 103,944
300 81,024 114,144
350 95,424 134,544
400 109,824 154,944
500 138,624 195,744
108,544 143,744 178,944
214,144
249,344
284,544
319,744
354,944
123,744 163,944 204,144
244,344
284,544
324,744
364,944
405,144
138,944 184,144 229,344
274,544
319,744
364,944
410,144
455,344
154,144 204,344 254,544
169,344 224,544 279,744
304,744
334,944
354,944
390,144
405,144
445,344
455,344
500,544
505,544
555,744
199,744 264,944 330,144
395,344
460,544
525,744
590,944
656,144
230,144 305,344 380,544
455,744
530,944
606,144
681,344
756,544
290,944 386,144 481,344
576,544
671,744
766,944
862,144
957,344
T
O P
W
I
,
F
T.
60
H
T O P L E N G T H, F T.
D T
8
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Waste Storage Pond Design Volume:
177,453
(cubic feet)
Approximate Design Dimensions Depth:
8
Width:
150
Length:
200
(select dimensions from Table 8c that result in a pond volume equal or greater than the design volume)
Volume Selected:
178,944
(cubic feet)
Step 8 - Estimate Construction Cost
Volume Selected x $0.10 per cu. ft. ~ Cost
178,944 x $0.10 = $17,894
(round to nearest $1,000)
Estimated Cost ~ $18,000
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Worksheet 8. Waste Storage Pond Volume Determination
Facility Name:
Worksheet 8 should
now be complete
for your operation.
Frank's Dairy
Prepared by: JEA
Location: Fort Morgan, CO
date: Dec-00
Checked by:
Runoff Volume Computations
Average Annual Rainfall:
Roofed Area (CN = 100)
Runoff
Paved Area (CN = 97)
Runoff
Annual Runoff %:
(
15
12.7
25 year-24 hour Rainfall:
inches
+
3.4
(
) x
1,000
3.4
inches
/ 12 =
1,342
Annual
25yr-24hr
Roof Area
Runoff Volume
Rainfall
Rainfall
(sq. ft.)
(cubic feet)
5.5
+
3.06
Annual
Runoff
43
Earthen Area (CN = 90 )
Runoff
Annual Runoff %:
(
12.7
1.9
) x
25yr-24hr
Area
(sq. ft.)
Runoff
+
2.36
2,000
) x
5.00
/ 12 =
1,420
Runoff Volume
(cubic feet)
x 3,630 =
77,359
Annual
25yr-24hr
Area
Runoff Volume
Runoff
Runoff
(acres)
(cubic feet)
Design Runoff Volume =
80,120
(cubic feet)
Storage Volume Computations
Design Runoff Volume:
80,120
(from calculations above)
Manure Solids Volume:
0
(Multiply tons/year by 50 cu. ft./ton)
Other Solids Volume:
0
Liquid Manure Volume:
0
(Divide gal/year by 7.5 gal/cu. ft.)
Process Wastewater Volume:
97,333
(Divide gal/year by 7.5 gal/cu. ft.)
Total Volume Required:
177,453
(cubic feet)
Approximate Design Dimensions Depth:
8
Width:
150
Length:
200
(select dimensions from Table 8c that result in a pond volume equal or greater than the required volume)
Volume:
178,944
(cubic feet)
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
However, a complete engineer’s evaluation ...
Job Name: Frank's Dairy
Location: Fort Morgan, CO
Climate Station: Fort Morgan, 3038
Computed By:
BASIC DATA
Solids & Slurry Inflow :
Other Liquid Waste Inflow:
Contributing Roof Area:
Contributing Concrete Lot Area:
Contributing Earth Lot Area:
25yr-24hr Precipitation Depth:
Annual FWS Evaporation:
Month
Jan.
Feb.
Mar.
Apr.
May
June
July
Aug.
Sep.
Oct.
Nov.
Dec.
Totals:
Precip.
(inches)
0.25
0.22
0.66
1.26
2.61
2.04
1.85
1.39
1.03
0.69
0.39
0.28
12.67
12/18/00
Date
REQUIRED POND VOLUME
0 cu. ft. /day
2000 gal. /day
1,000
2,000
192,000
3.4
sq. ft.
sq. ft. (CN 97)
sq. ft. (CN 90)
inches
STORAGE POND DESIGN DATA
Bottom Width:
102 ft.
110 ft.
Residuals Storage:
46,555 cu.ft.
Bottom Length:
25yr. Storm Runoff:
Design Volume:
45,184 cu.ft.
91,739 cu.ft.
Inside Slope:
Design Depth:
Evaporation Area:
Freeboard:
Available Storage:
101% of design
48.0 inches
INFLOW
Monthly Contribution from Precipitation
Waste Inflow
Earth Lot
Concrete Lot
Roofed Area
On Pond Solids Liquids
%P
(cu. ft.)
%P
(cu. ft.)
%P
(cu. ft.) (cu. ft.) (cu. ft.) (cu. ft.)
10%
400
22%
9
100%
21
494
0
8,278
10%
352
18%
7
100%
18
435
0
7,477
10%
1,056
30%
33
100%
55
1,304
0
8,278
10%
2,016
40%
84
100%
105
2,489
0
8,011
18%
7,517
50%
218
100%
218
5,155
0
8,278
18%
5,875
46%
156
100%
170
4,029
0
8,011
17%
5,032
45%
139
100%
154
3,654
0
8,278
14%
3,114
45%
104
100%
116
2,745
0
8,278
15%
2,472
45%
77
100%
86
2,034
0
8,011
13%
1,435
42%
48
100%
58
1,363
0
8,278
10%
624
25%
16
100%
33
770
0
8,011
10%
448
25%
12
100%
23
553
0
8,278
30,341
903
1,056
25,023
0
97,463
1.90 inches
5.42 inches
12.67 inches
Seepage Rate:
3
6
11220
2
H:1V
ft.
sq. ft
ft.
0.000 in./day
150
158
8
Top Width:
Top Length:
Total Depth:
Design Surface Area:
Storage Volume:
Freeboard Volume:
23,700
92,808
40,104
Total Volume:
136,608
OUTFLOW
Total
Surface
Seepage Planned
Inflow
Evaporation
Loss
Drawdown
(cu.ft.) (inches) (cu. ft.) (cu. ft.) (acre-in.)
9,201
1.44
1,346
0
0
8,288
1.68
1,571
0
0
10,725
2.64
2,468
0
0
12,704
4.32
4,039
0
16
21,384
5.76
5,386
0
0
18,241
6.96
6,508
0
0
17,256
7.20
6,732
0
0
14,357
6.48
6,059
0
0
12,680
4.80
4,488
0
16
11,181
3.36
3,142
0
0
9,454
1.92
1,795
0
0
9,314
1.44
1,346
0
0
154,786
48
44,880
0
32
Total
Outflow
(cu. ft.)
1,346
1,571
2,468
62,119
5,386
6,508
6,732
6,059
62,568
3,142
1,795
1,346
161,040
STORAGE
Monthly
In - Out
(cu. ft.)
7,855
6,717
8,257
-49,415
15,999
11,734
10,524
8,298
-49,888
8,040
7,658
7,967
results in a smaller pond, reducing cost ~ $4,000 for Frank
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop
Section 8 - Wastewater Storage Pond Design
Colorado CNMP Workshop