﻿HYDROLOGY 
  OF 
  NEW 
  YORK 
  39 
  

  

  265,000 
  cubic 
  feet 
  per 
  second. 
  The 
  recent 
  studies 
  indicate 
  that 
  

   the 
  extreme 
  low 
  flow 
  of 
  a 
  cycle 
  of 
  minimum 
  years 
  may 
  not 
  be 
  

   more 
  than 
  60 
  per 
  cent 
  to 
  70 
  per 
  cent 
  of 
  this 
  figure. 
  From 
  this 
  

   point 
  of 
  view, 
  the 
  people 
  of 
  the 
  State 
  of 
  New 
  York 
  have 
  great 
  

   interest 
  in 
  any 
  project 
  which 
  would 
  tend 
  to 
  decrease 
  the 
  low- 
  

   water 
  runoff 
  of 
  that 
  stream. 
  The 
  figures 
  obtained 
  by 
  the 
  Deep 
  

   Waterways 
  Survey, 
  substantiate 
  this 
  statement. 
  Such 
  interest 
  is 
  

   equally 
  pronounced 
  in 
  the 
  case 
  of 
  the 
  St 
  Lawrence 
  river. 
  

  

  The 
  measurements 
  of 
  discharge 
  of 
  a 
  number 
  of 
  inland 
  streams 
  

   of 
  New 
  York 
  indicate 
  considerable 
  variation 
  in 
  the 
  water 
  yield 
  

   in 
  different 
  parts 
  of 
  the 
  State. 
  Genesee 
  river, 
  in 
  1895, 
  gave, 
  with 
  

   a 
  rainfall 
  of 
  31 
  inches, 
  a 
  minimum 
  flow 
  for 
  the 
  year 
  of 
  only 
  6.67 
  

   inches. 
  The 
  catchment 
  area 
  of 
  this 
  stream 
  is, 
  as 
  already 
  stated, 
  

   mostly 
  deforested, 
  whence 
  it 
  results 
  that 
  serious 
  floods 
  are 
  

   frequent. 
  

  

  The 
  lowest 
  annual 
  runoff 
  thus 
  far 
  measured 
  in 
  the 
  State 
  of 
  New 
  

   York 
  is 
  that 
  of 
  the 
  Hemlock 
  lake 
  catchment 
  area, 
  where, 
  in 
  1880, 
  

   the 
  total 
  runoff 
  from 
  an 
  area 
  of 
  48 
  square 
  miles 
  was 
  only 
  about 
  

   3.35 
  inches. 
  

  

  Oswego, 
  Mohawk, 
  and 
  Hudson 
  rivers 
  and 
  their 
  tributaries 
  in 
  

   this 
  State 
  all 
  have 
  large 
  pondage 
  on 
  natural 
  lakes, 
  which, 
  with 
  

   other 
  conditions, 
  tend 
  to 
  maintain 
  the 
  low-water 
  flow. 
  Croton 
  

   river 
  presents 
  surface 
  geologic 
  conditions 
  which 
  tend 
  to 
  increase 
  

   its 
  low-water 
  flow. 
  Without 
  going 
  into 
  detail, 
  we 
  may 
  say 
  that 
  

   these 
  streams 
  will 
  yield 
  a 
  minimum 
  flow 
  of 
  about 
  0.2 
  of 
  a 
  cubic 
  

   foot 
  per 
  second 
  per 
  square 
  mile. 
  Variations 
  from 
  this 
  limit 
  are 
  

   given 
  in 
  the 
  chapters 
  specially 
  discussing 
  minimum 
  flow. 
  

  

  As 
  a 
  typical 
  flood 
  stream 
  of 
  the 
  State 
  we 
  have 
  Chemung 
  river, 
  

   where 
  serious 
  floods, 
  due 
  to 
  deforestation 
  of 
  a 
  mountainous 
  catch- 
  

   ment 
  area, 
  have 
  become 
  so 
  common 
  as 
  to 
  necessitate 
  the 
  carrying 
  

   out 
  of 
  extensive 
  protection 
  works 
  at 
  the 
  large 
  towns 
  on 
  that 
  

   stream. 
  

  

  Value 
  of 
  ivater 
  to 
  industries. 
  Water 
  power 
  is 
  extensively 
  sold 
  

   at 
  Oswego, 
  Cohoes, 
  and 
  Niagara 
  Falls, 
  and 
  to 
  some 
  extent 
  at 
  

   Rochester. 
  It 
  will 
  also 
  be 
  extensively 
  sold 
  at 
  Massena 
  when 
  the 
  

   development 
  there 
  is 
  completed. 
  

  

  