WATER-STAGE REGISTERS 



269 



gauges with bench marks for checking the record and maintaining 

 the datum. The well and the house should be located far enough 

 back from the river to be out of danger from floating ice or 

 drift and to provide sufficient protection for the well and pipes 

 to prevent freezing. A permanent ladder should extend to the 

 bottom of the well, so that the float and intake can be readily 



FIG. 149. Method of Installing Automatic Water Stage Register. 



inspected. If the register is to be maintained for a long period 

 the well should be lined with concrete, otherwise a heavy plank 

 lining may be used. The intake pipe should be placed well 

 below the lowest stage of the river and provided with a screen 

 for keeping out silt and foreign material. It should also be pro- 

 vided with check gate as it enters the well, so that the flow can 

 be reduced if necessary to eliminate wave action. 



