100 



TrMT^actions. — Miscellaneous. 



I append a table of Taieri Eiver floods, data from Danedin Meteoro- 

 logical Observatory ; also a map of the Taieri Basin (pi. XI.) 



Date. 



Direction of Storm 

 Average. 



Total Eainf all 

 in Inches. 



1867— November 19th to December 1st. . 

 1868— January 29tli to February 8th . . 

 1876— January 22nd to 24th . . . . 

 1877— February 2nd to 9th 

 1879— March 24th to April 1st . . 



June 28th to 30th 



N.W. to N.E. 

 N.E. to S.W. 



S. to S.W. 



N.E. to S.W. 



N.E. to W. 



S.E. to S. 



4-002 

 5-246 

 4-960 

 6-200 

 4-728 

 4-560 



Abt. VII. — On the Reclamation of Waste River Beds. 

 By A. D. DoBsoN, F.G.S. 

 [Read before the PhilosopJdcal Institute of Canterbury, 2nd June, 1881.] 

 One of the most striking features of the Canterbury Plains is the great area 

 of ground occupied by the shingle beds of the rivers, an area quite out of 

 proportion to the size of the rivers were they confined so as to flow in one 

 deep channel instead of spreading as they now do in numerous shallow 

 streams over their wide shingle beds. 



From the Waipara to the Eangitata the area of the shingle beds is at 

 least 100,000 acres, one half of which would be amply sufficient for the 

 water-way were the rivers properly regulated. Not only do the rivers 

 occupy a much greater area than is at aU necessary for the water-way, but 

 in the lower part of their courses they are continiially filling up their beds 

 with the shingle brought down from the mountains, and cutting fresh 

 channels in the adjoining lands, thus destroying valuable property, and 

 being a continual source of expense and anxiety to those who live on their 

 banks. 



The Waimakariri in Canterbury, and the Wairau in Marlborough, are 

 well-known illustrations of this statement. 



All rivers have a tendency to raise their beds in the lower part of their 

 courses, this action being slowest when fine silt only is brought down, such 

 as that deposited by the Nile and Mississippi, and most rapid in shingle- 

 bearing torrents, such as our own rivers. 



Even in the case of large rivers with long courses and little fall, the rise 

 of the river bed, and often the adjoining overflowed country, is more rapid 

 than would be expected by a casual observer. From long before the 

 JjjstoriQal period, the Nile has been steadily raising its bed, but as its 



