80 



DIVISION OF WATER RESOURCES 



the arrangement to supi)ly water for tule Tank No. 2 and also 'the still 

 well for measuring- the amonnt of water used. Because of the volume 

 of water required to supply tule Tank No. :>, a different arrangement 

 was necessary there. This tank was supplied through an automatic 

 float-valve feed connected to a supply tank of larger capacity. Plate 

 XIV shows the arrangement for regulating the supply of water and 

 measuring the amount used in tule Tank No. 3. 



Beginning November 22, 1930, Tanks Nos. 1, 2, and 3 were main- 

 tained with free water surfaces until January 29, 1931, when they 

 w'ere planted with tules {Scir])iis olnciji). During the installation of 

 the equipment, the old tules around the tanks were broken down and 

 the tanks were not completely surrounded with new growth until about 

 ]\Iay, 1931. Prior to May 15 the side exposure of Tank No. 2 was some- 

 what greater than that of Tank No. 3 but after that date the surround- 

 ing growth completely hid the rims of both tanks and thereafter the 

 exposure of the tules in Tanks Nos. 2 and 3 Avas similar to tliat of the 

 natural swamp tules. 



PLATE XVI 



1,%^ 



•i 



-.^> 



ft. 



VIEW OF TANK NO. 1, TAKEN OCTOBER 31, 1931. 



