258 CONSERVATION OF GROUND WATER 



propriators the amount of impairment each caused to the static 

 head of a prior user of users. ... I desire tentatively to express 

 the view that the point of diversion is not at the surface where the 

 water either by its own static head or by artificial means emerges, 

 but at the point or points where the appropriator takes it from the 

 underground source. I have doubt as to whether an appropriator 

 of underground water appropriates static pressure or head as a 

 concomitant of the water he appropriates, even when he appropri- 

 ated by diligence before the statutory method was in force. 



INTERRELATIONSHIP OF SUBDIVISIONS OF MAJOR DRAINAGE 

 BASINS 



In the early stages of water development it is possible to treat 

 various subdivisions of a drainage basin as separate and inde- 

 pendent units, even when the units obviously are dependent 

 upon a common source of water. As the separate areas ap- 

 proach full utilization of available supplies, however, their 

 interdependence becomes more and more apparent and the 

 need for establishing the rights as between areas grows greater. 

 The lack of adequate hydrologic data has hampered or de- 

 layed such determinations in many areas where water prob- 

 lems have become acute, but even where there is a substantial 

 volume of data the problem is likely to be complex. The water 

 rights of individuals in the separate areas are especially diffi- 

 cult to adjudicate if the areas are in different states and subject 

 to different water laws or doctrines. Economics may be a major 

 factor, bringing in arguments as to the relative cost of neces- 

 sary development and the relative value of the water in various 

 areas. 



Interstate streams have produced the most difficult problems 

 to date, where utilization of water in one state is dependent 

 upon flow from source areas beyond the jurisdiction of that 

 state. The problems dealing with water not yet developed 

 and utilized are particularly difficult to solve, for they bring 

 up the question of the respective claims of source areas and 

 of the areas lower in the drainage basin. The states, which 

 are the arbiters of most water disputes, become protagonists 



