244 H. G. McKINNEY. 



A factor of much importance in connection with the flow in 

 the river Darling, and one which has a great tendency to com- 

 plicate the question of water-rights, is the intermittent character 

 of the flow in a number of its tributaries. When the channel of 

 a river becomes quite dry, the loss of water from the first freshet 

 is enormous. Cases have come under the notice of the writer in 

 which the water in a creek after a period of drought has flowed 

 only from two to three miles per day, while the same discharge 

 after the channel was saturated covered twenty -five to thirty miles 

 per day. Thus a small flow which would merely keep the bed of 

 a channel saturated, might be the means of accelerating by weeks 

 the flow of a succeeding freshet. On the other hand a work of 

 comparatively trifling importance which interfered with a small 

 flow might be the cause of extensive loss. Numerous cases of this 

 kind are conceivable on tributaries of the River Darling. For 

 instance, it is not difficult to imagine circumstances under which 

 injudicious interference with the waters of the Namoi or of the 

 Mclntyre would have a perceptible effect on the River Darling 

 hundreds of miles distant. But, as already indicated, the storage 

 of water on the higher parts of the catchments of tributaries of 

 the Darling may be made distinctly beneficial. The question of 

 benefit or injury in such cases, so far as navigation is concerned, 

 would have to be judged by the Federal Government, or the 

 Inter-State Commission. 



Throughout the lower parts of the River Darling few difficulties 

 are likely to arise. The Upper and Lower Tallywalkas on the 

 east side of the river, and the Great Ana Branch on the west are 

 the only outflow channels of any considerable importance, and 

 though they are capable of great improvement they are so much 

 above the bed of the river that no alterations likely to be attempted 

 will affect navigation. 



Licenses under the Water Rights Act have been granted for a 

 number of pumping plants along the course of the Darling, but 

 considering the uncertainty of the rainfall and the dryness of the 

 district, the number of these pumps is surprisingly small, being 



