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. OSTP Non-Level Pressure Distribution <br /> UNIVERSITY ` � <br /> Minnesota Poflution Design Worksheet OF MINNESOTA �� " ' <br /> Control A enc ,�_��.� <br /> 1. Enter soil treatment area (STA)length in order of the Highest Elevation to the Lowest Elevation: <br /> Lateral 1 Pipe Elevation 91.4 ft Length of STA from manifold 25 ft Highest <br /> Lateral Z Pipe Elevation 90.2 ft Length of STA 25 ft <br /> Lateral 3 Pipe Elevation ��ft Length of STA ��ft <br /> Lateral 4 Pipe Elevation ��ft Length of STA C�ft <br /> Lateral 5 Pipe Elevation ��ft Length of STA �_�ft Lowest <br /> 2. Calculate Change in Elevotion over the laterals <br /> =Highest Elevation (Lateral 1)-Lowest Elevation(Last Lateral above) 91.4 ft - 90.2 ft = 1-2 ft <br /> 3. Select Minimum Average Head: 1.0 ft <br /> Use 1.0 ft for dwellings using 1/4 inch or 3/16 inch holes. <br /> Use 2.0 ft for dwellings using 1/8 inch hotes;or,for MSTS or other establishments using 1/4 inch or 3/ib inch holes. <br /> This worksheet cannot be used for a Minimum Average Head of 5.0 feet. Design must be modified or valving must be used to <br /> equalize flow. <br /> 4. Calculate the Totol Heod =Minimum Averoge Heod (Line 3)+Chonge in E(evation (Line 2) <br /> 1.0 ft + 1.2 ft = 2.2 ft <br /> 5. Calculate Pressure Head for Each Latera( <br /> A. Highest trench elevation (Pipe Elevation 1):Pressure Heod equals Minimum Average Head (Line 3) <br /> B.All other trenches:Pressure Heod equals Minimum Avernge Heod (Line 3)ptus the Change in Elevation from Lateral 1. <br /> Minimum Avera e Head tievation or tievation or <br /> 4 �atP�a� � i arP��� Pressure Head <br /> �at 1 1.0 ft + [ 91.4 ft - 91.4 ft] = 1.0 ft <br /> Lat 2 1.0 ft + [ 91.4 ft - 90.2 ft] = 2.2 ft <br /> Lat 3 �ft + [�ft -��ft] _ �ft <br /> Lat 4 �ft + [�ft -�ft] _ �ft <br /> Lat 5 �ft + [��ft -��ft] = C�ft <br /> 6. Determine the Flow Rate per Hole � = 1 9 . 65 cd 2 � <br /> Select a Perforation Diameter and the corresponding gallons per minute <br /> from the Perforation Discharge table below, adjusting as needed. c=0.60;d=perforation diameter; h=pressure head <br /> or Calculate Perforation Discharge(�in GPM: <br /> Lat 1 Pressure Head 1.0 ft Perforation Diameter 1/4 - 0.74 GPM 0.25 Highest <br /> Lat 2 Pressure Head 2.2 ft Perforation Diameter 1/4 = 1.09 GPM 0.25 <br /> Lat 3 Pressure Head � ft Perforation Diameter� - � GPM FALSE <br /> Lat 4 Pressure Head �� ft Perforation Diameter�� - �� GPM FALSE <br /> �----- <br /> ,_.� �.---- -- ��--, �-� - - - -. f� - f-1 ,-�.. _.. -- <br />