Utah Administrative Code
Topic - Environmental Quality
Title R317 - Water Quality
Rule R317-401 - Graywater Systems
Section R317-401-6 - Construction and Installation of Irrigation Systems
Current through Bulletin 2024-06, March 15, 2024
6.1. Each distribution zone shall have a minimum effective irrigation area for the soil characteristics and vegetation needs.
6.2. The area of a distribution zone shall be equal to the total length of the perforated pipe sections within the distribution zone multiplied by the width of the proposed trench. The required square footage shall be determined using Table 4 or Table 5.
TABLE 4
Subsurface Irrigation System Design
Soil Characteristics |
Subsurface Irrigation System Area Loading, gallons of graywater per day per square foot |
Coarse Sand or Gravel |
5 |
Fine Sand |
4 |
Sandy Loam |
2.5 |
Sandy Clay Loam |
1.6 |
Clay Loam |
1.1 |
Clay with Sand or Gravel |
0.8 |
TABLE 5
Drip Irrigation System Design
Soil Characteristics |
Minimum Number of Emitters, per gallon per day |
Maximum Emitter Discharge, gallons per day |
Coarse Sand or Gravel |
0.6 |
1.8 |
Fine Sand |
0.7 |
1.4 |
Sandy Loam |
0.9 |
1.2 |
Sandy Clay Loam |
1.1 |
0.9 |
Clay Loam |
1.6 |
0.6 |
Clay with Sand or Gravel |
2.0 |
0.5 |
6.3. The lowest point of any distribution zone shall be at least two vertical feet above the maximum groundwater table. Applicant shall provide sufficient groundwater data to the regulatory authority. Subsection R317-4-4.1.B.4 may be used to determine maximum groundwater elevation.
6.4. Subsurface drip irrigation system.
Subsurface drip irrigation systems shall be constructed so that:
6.5. Subsurface Irrigation System.
Subsurface irrigation systems consisting of pipe and gravel or chambers may be used for dispersal of graywater.
TABLE 6
Lateral Construction Details
Description |
Minimum |
Maximum |
Number of drain lines per zone |
1 |
--- |
Length of each perforated line, feet |
--- |
150 |
Bottom width of trench, inches |
6 |
36 |
Total depth of trench, inches |
9 |
36 |
Spacing of lines, wall to wall, feet |
4 |
--- |
Depth of backfill, inches |
6 |
--- |
Depth of aggregate cover over lines, inches |
2 |
--- |
Depth of aggregate beneath lines, inches |
3 |
--- |
Grade of drain lines, inches per 100 feet |
Level |
4 |
TABLE 7
Minimum Standards for Graywater Sewer and Distribution Pipe Materials (a)
Acceptable Graywater Pipe Materials
Type of Pipe |
Minimum Standard |
Acrylonitrile-Butadiene Styrene (ABS) |
ASTM (b), D-2680, D-2751, F-628 |
Polyvinyl Chloride (PVC) |
ASTM D-2665, D-3033, D-3034 |
Acceptable Distribution Pipe Materials
Type of Pipe |
Minimum Standard |
ABS |
ASTM D-2661, D-2751 |
Polyethylene (PE) |
Smooth Wall ASTM D-3350 |
PVC |
ASTM D-2665, D-3033, D-3034, D-2729(c) |
Notes: