8 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 
Filter galleries are now in process of construction at the 
head works where the surface water is tunneled into the bed of 
the river and filtered through sand before entering the head 
works. The bacterial count of the water before entering the 
filtration galleries shows 130 colonies per cu. em. even in their 
incompleted condition. 
The total consumption of water in Los Angeles is as great 
as that of San Francisco— 34,000,000 gallons a day in summer, 
18,000,000 gallons a day in winter. 
The river still increases in volume up to about a mile above 
Tropico. At this pomt the main head works of the system 
are built, the flow is between 65 and 75 cu. ft. There 1s a slight 
increase in volume until Columbia Street is reached, where 
the river disappears altogether as the depth to bed rock 
increases. 
During the five years which the city owned its water supply, 
the development of water has been given close attention by 
Superintendent Mulholland. With the idea of increasing the 
total supply different sets of wells have been bored and tunnels. 
built. 
The Buena Vista Street wells located in Elysian Park aad 
pumping to supply the gravity reservoirs on Beaudry Avenue 
and Elysian Park, come from a 4000 foot tunnel under the 
river bed and supply about 3,000,000 gallons daily. The 
bacterial count varies from about 41 to about 150 bacteria 
to the cu. em., depending on the season of the year. In summer 
time the count runs higher as the water is low. Two other 
wells located at the end of the West Jefferson Street car line 
supply 1,000,000 gallons per day and the bacterial count is. 
between 80 and 100 colonies. 
The largest part of the city water, however, is derived from 
the Los Angeles river. <A trip to the head works occupies the 
greater part of a day and at this poimt the bacteriological 
tests average from 600 to 2380 colonies per cu. em. Above 
the head works to the northeast the water is on the surface. 
It is in this region that the San Fernando farmers drain the 
river for agricultural purposes and in years past their stock 
was pastured on the banks of the stream. Dr. Powers has 
watched this portion of the river most closely and in years 
past has pulled careasses of sheep, horses and mules out of 
the river. At the present time these conditions are ereatly 
improved. 
From the head works 12 miles nouthwest the city water 
runs in a cement conduit into the city mains. Between the 
head works and the Crystal Springs house, located on the other 
side of Griffith Park, the river again flows on the surface for 
a distance of several miles and enters the city mains at Crystal 
