Arthub. — On the Taieri Ri^er Floods. 99 



embankment, 6 chains in length and 15 feet high, would retain 217,800,000 

 cubic feet over an area of 500 acres. The catchment area above this point 

 is 59 square miles, which, with a rainfall run-off of 1-5 inches, gives a daily 

 discharge of 205,603,200 cubic feet. The cost of this dam, if of masonry, 

 I estimate at £3,115. There are other good sites on this river, but none 

 on the Kyeburn, Sutton, or Lee Stream. 



Waipori Reservoir. 



The valley of the Waipori also offers facilities for impounding flood 

 waters above the junction of the Yerterburn, and near the outfall of the 

 sludge-channel. I am not so familiar with this spot as with those sites 

 above described, nor do I think it so good. Still, here also there is an 

 area which I estimate at 900 acres suitable for a reservoir. An embank- 

 ment or dam, 10 chains in length and 33 feet high, would impound about 

 588,060,000 cubic feet of water, the inclination of the flat being 7 feet per 

 mile. If of masonry, its cost would be £12,000 ; but probably a careful 

 survey would show that the dam need not be so long, and, consequently, 

 not so costly. This Waipori reservoir would not, of course, be a check on 

 the floods of the Taieri itself, and may therefore be left out of consideration 

 until the money required for its construction is available. At the same 

 time, it would benefit the Henley estate and others of the low-lying lands 

 in that quarter, while indirectly it would relieve the outflow of the Taieri 

 by the lower gorge into the sea. 



In each of the above dams, self-acting sluices, openings or culverts, would 

 be necessary, the particular form being a detail which need not here be 

 gone into. 



Neither have I particularly referred to the embankment of the Taieri 

 Eiver on the Lower Taieri Plain, from Outram seawards. I would only 

 remark that, while I think it probable the money spent on this might have 

 been expended more profitably in the construction of dams further iip the 

 river m the interior, there can be no question as to the benefit the embank- 

 ment has been to the lands on the right or west bank of the river. This, 

 however, is secured at the expense of the lands on the east side of the 

 river, of the channel of the river, and of the bridges on the river. 



In concluding this paper, I would say that the facts I have given go to 

 prove that nearly all the flood-water which could be impounded at the 

 Taieri Lake, may be confined above the Styx Eiver at much less cost, 

 and that an exhaustive survey should be initiated without loss of time, 

 first to determine where the greatest rainfall occurs on the catchment area, 

 and next the precise capabilities of the various reservoir sites which I have 

 indicated, mj own calculations of the latter being only approximate. 



