(716) 
simple means of estimating the population per acre and also the water require- 
ment, area by area, of the city, once we understand the nature af each area. 
In Figure 2 we see a typical congested native section whose population 
averages an estimated 700 people per acre, but whose population may be ex- 
pected to rise to about 1,000 per acre. 
  
Fig. 2, 
In the photograph, this area measures about 240 acres. On the basis of 10 
gallons per capita and 700 people per acre, the area now requires about 1,700,000 
gallons of water daily. To meet the normal increase of population a minimum 
of 2'/; million gallons of water daily for domestic use at present per capital 
consumption should be provided. Further estimates, of course, need to be made 
concerning the increasing demands per capita. While these figures cannot al- 
ways be used as concrete statistical data they do indicate the order or size of 
the water problem in this section of the town. 
This has been a brief generalized presentation of a typical problem but it 
indicates how by measurement of easily definable areas, whose characteristics 
have previously been explored in sample areas, the rapid evaluation of many 
urban problems may be made. 
With further development of systems of relating various data to the struc- 
tural and functional patterns of the city as observed in aerial photography, the 
urban analyst and planner can be considerably aided in his daily tasks.