Nevada Administrative Code › Chapter 444 - Sanitation › SEWAGE DISPOSAL › Absorption and Treatment of Effluent › Section 444.8396 - Pressure distribution system: Design criteria

Current through June 11, 2024
1. A
				pump must be used to pressurize a pressure distribution system. A siphon may be
				used in lieu of a pump if adequate elevation head is available. The active
				dosing volume must be approximately 10 times the total volume of the
				distribution pipe.
2. A solid
				delivery pipe which goes from the dosing tank to the perforated distribution
				piping must be placed below the frost line. The delivery pipe must maintain a
				downward slope from the distribution lines to the dosing tank to ensure that
				the line will drain between discharges. Check valves and other devices that
				prevent backflow through the pump must not be used so that effluent may, when
				necessary, drain back to the dosing tank to protect the pipe from
				freezing.
3. To reduce the
				potential for plugging and clogging the distribution lines, the diameter of the
				discharge hole must be 3/8 inch or more. The rate of discharge for
				various-sized holes at various pressures are set forth in the following table:
DISCHARGE RATES AT VARIOUS PRESSURES
							 (gallons per minute)
Pressure
Hole Diameter
Per Foot of Water
Per Square Inch
3/8 Inch
7/16 Inch
1/2 Inch
1
0.43
1.66
2.26
2.95
2
0.87
2.34
3.19
4.17
3
1.30
2.87
3.91
5.10
4
1.73
3.31
4.51
5.89
5
2.17
3.71
5.04
6.59
4.
				Friction losses in schedule 40 plastic pipe are listed in the following table:
FRICTION LOSS IN SCHEDULE 40 PLASTIC
							 PIPE; C = 150 (ft/100 ft)
Pipe Diameter (inches)
Flow in gallons per minute
1
1 1/4
1 1/2
2
3
4
6
8
10
1
0.07
2
0.28
0.07
3
0.60
0.16
0.07
4
1.01
0.25
0.12
5
1.52
0.39
0.18
6
2.14
0.55
0.25
0.07
7
2.89
0.76
0.36
0.10
8
3.63
0.97
0.46
0.14
9
4.57
1.21
0.58
0.17
10
5.50
1.46
0.70
0.21
11
1.77
0.84
0.25
12
2.09
1.01
0.30
13
2.42
1.17
0.35
14
2.74
1.33
0.39
15
3.06
1.45
0.44
0.07
16
3.49
1.65
0.50
0.08
17
3.93
1.86
0.56
0.09
18
4.37
2.07
0.62
0.10
19
4.81
2.28
0.68
0.11
20-24
5.23
2.46
0.74
0.12
25-29
3.75
1.10
0.16
30-34
5.22
1.54
0.23
35-39
2.05
0.30
0.07
40-44
2.62
0.39
0.09
45-49
3.27
0.48
0.12
50-59
3.98
0.58
0.16
60-69
0.81
0.21
70-79
1.08
0.28
80-89
1.38
0.37
90-99
1.73
0.46
100-149
2.09
0.55
0.07
150-199
1.17
0.16
200-249
0.28
0.07
250-299
0.41
0.11
300-349
0.58
0.16
350-399
0.78
0.20
0.07
400-449
0.99
0.26
0.09
450-499
1.22
0.32
0.11
500-599
0.38
0.14
600-699
0.54
0.18
700-799
0.72
0.24
800-899
0.32
900-999
0.38
1000 or more
0.46
5.
				Laterals must be spaced so that they are not less than 4 feet or more than 6
				feet apart. The outside laterals must be placed at a distance from the
				perimeter of the bed that is equal to 1/2 of the distance between the
				laterals.
6. Distribution lines in
				the pressure distribution system must be looped.
7. The required lateral pipe diameters for
				various hole diameters, hole spacings, and lateral lengths for plastic pipe are
				shown in the following diagram:
Click here
				  to view image.
8. Manifold diameters for various manifold
				lengths, number of laterals, and lateral discharge rates for plastic pipe are
				shown in the following diagram:
Click here
				  to view image.
Added to NAC by Bd. of
				  Health by R129-98, eff. 3-25-99
NRS
					 439.200,
					 444.650