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ONStTl' Univeristy of Minnesota sCVYA6! TRCATMEN'T Non-Level Pressure Ditribution Worksheet PwooRwar ,�'c,',,"C� 1. Enter each system lateral elevation and len h in order of highest to lowest elevation Latera� 1 Elevation 1001.6 ft Length of pipe 38 ft Lateral2 Elevafion 999.6 ft Length of pipe 38 ft Lateral 3 Elevation ft Length of pipe ft Lateral 4 Elevation ft Length of pipe ft Lateral 5 Elevation ft Length of pipe ft 2. Calculate change in elevation over the laterals. Highest elevation-lowest elevation: 1001.6 - 999.6 = 2.0 feet 3. Calculate the Total Head=head at orifices(either 1 or 2 ft)+change in elevation(2) Enter 1 ft if design if for a single family home or 2 R for anything etse(min design pressure head at perforation) 01 ft + 2.0 ft = 3.0 feet This worlcsheet can not be used if greater�an 5 feet. Design must be modified or valving must be used to equalize flow. 4. Calculatie pressure head for each lateral 1. Highest Trench Elevation(E1)the Head= 1 or 2 feet 2. For all other laterals the pressure head is calculated as 2 feet plus the change in elevation from Lateral 1. Laterall Elevation 1001.6 1.0 ft Lateral 2 Elevation 999.6 1 + [E1 -E2] = 1 + [ � - 999.6 ]= 3.0 ft Lateral 3 Elevation 0.0 0 + [E1 -E3] = 0 + [ ##### - 0.0 ]= 0_0 ft Lateral 4 Elevation 0.0 0 + [E1 -E4] = 0 + [ ##### - 0.0 ]= 0.0 ft Lateral 5 Elevation 0.0 0 + [E1 -E5] = 0 + [ ##### - 0.0 ]= 0.0 ft 5. Determine flow rate per hole(See figune E-6). Se/ect a perforation diameter and the corr�sponding gallons per minute inteipolatin as needed. Lateral 1 Pres 1.0 Pert Diameter 1/4 = 0.74 gpm Lateral 2 Pres 3.0 PerF Diameter 1/4 = 128 gpm Lateral 3 Pres 0.0 Perf Diameter = gpm Lateral 4 Pres 0.0 Pert Diameter = gpm Lateral 5 Pres 0_0 Pert Diameter = gpm 6. Calculate flow in gallons per minute for Lateral 1 -Select a spacing and enter in box. Number of perforations=[(len of ipe-2)/spacingj+1 [( 38 ft-2ft) / �3 ft]+1 = 13 perforations(Check figur�e E-4 to make sure it is ok) Flow=number of perforations x ftow rate 13 perf x 0.7 gpm = 9.6 gpm for Lateral 1 7. Calculate the gallons per minube per foot for Lateral 1 This value will then be used to make sure the gal/on per minute per foot is equivalent in each lateral. Gallons/length= 9.6 gpm i 38 ft= 0.25 gpm/ft E-6 Perforation Dischar e in GPM E-4 Maximum Number of 1/4 inch perforations Pressure er lateral to uarantee<10%dischar e variation Head Pertoration Diameter in inches Perf feet 1/8 3/16 7/32 1/4 Spacing 1 0.18 0.42 0.56 0.74 feet 1 in 1.25 in 1.5 in 2.0 in 1.5 0.22 0.51 0.68 0.90 2.5 8 14 18 28 2 026 0.59 0.80 1.04 3.0 8 13 17 26 2.5 0.29 0.65 0.88 1.17 3.3 7 12 16 25 3 0.32 0.72 0.98 1.28 4.0 7 11 15 23 4 0.37 0.83 1.13 1.47 5.0 6 10 14 22 5 0.41 0.94 12& 1.65 Page 1 of 2