40 BULLETIX 57. U. S. DEPAETMENT OF AGRICULTUEE. 



Dimensions for automatic siphons. 



liead. 



I'iaraotor of- siphon.. 



Uiameter of bell 



Diiuneier of disi-harg 



Dnnvint; dopth 



Depth of trap 



AVidth of trap 



Height above (3oor 



Clearance under bell 



Diameter of carrier 



Invert to discharge line 



.\verage discharge per second cubic feet 



Inches. Inches, i Inches. 



<?/9rs c//^Af^£-/? 



4 

 204 



4 

 12 



4 

 14 

 13 

 12 



8f 



2 

 4-6 

 22f 



15 

 6 

 23 

 22 

 14 

 9i 

 3" 

 6-8 

 334 



0.35 



0.73 



X. 



i 



! 

 i 



■^"77'/e 



4- 



Fig. 32.— /Ground plans of tile sewage disposal systems. 

 THE FINAL DISPOSAL SYSTEM. 

 DISPOSAL BY SURFACE OR SUBSURFACE DISTRIBUTION'. 



^Vhere the soil is porous or sandy and there is plenty of area 

 available which is used for no other purpose, the sewage froni the 

 septic tank may be discharged through 4-inch distribution tile laid 

 on the surface of the ground in gridiron or herringbone fashion. 

 Four hundred and fifty to 500 square feet of area are necessary for 

 each person served if the soil is very porous and sandy, and the soil 

 should either be tile-drained or have natural underdrainage. 



