1. Drip System Design for a Difficult Siteby
David Morgan

2. Design Parameters 3 Bedroom 2 bath home Soil loading rate
450 gallons, 150 g/d/bedroom
Soil loading rate
0.2 g/d/ft2, from soil report
Depth to seasonal high water table
20 inches, from soil report
Depth to restrictive horizon
36 inches, from soil report
Slope
2 to 4%, from site evaluation

3. Preliminary Design 2250 ft2 required 1125 linear feet drip tube
450 g/d ÷ .2 g/d/ft2
1125 linear feet drip tube
2250 ft2 ÷ 2 ft drip tube spacing
3 laterals
1125 lft req ÷ 400 ft (available area) = 2.8
10 g/m Operating flow
1200 lf ÷ 2 ft dripper spacing X 1 g/h ÷ 60 m/h
14.5 g/m Flushing flow
3 lines X 1.48 g/m(2 ft/sec) + 10 g/m operating
48 minutes maximum run time per day
{[(2 ft X 2 ft) X .2 g/d/ft2] ÷ 1 g/h} X 60 m/h
45 minutes Actual run time per day
450 g/d ÷ 10 g/m (dosing rate)

4. Preliminary Design

5. Preliminary Design 33 psi operating loss on drip tube
93 psi flushing loss on drip tube
WE MUST REDESIGN

6. Modified Design

7. Modified Design 4 psi operating loss on drip tube
24 psi flushing loss on drip tube
NOW THAT WILL WORK

8. Modified Design for Quicker Pressurization

9. Typical Control Valve How well do they drain? 24VAC NC Diaphragm
Lower Body
Diaphragm
Diaphragm Spring, 2 psi
Upper Body
Flow Control Knob
Solenoid
Manual Override

10. Questions or do you want to head down the road?
Thank You
Questions or do you want to head down the road?