﻿HYDROLOGY 
  OP 
  NEW 
  YORK 
  471 
  

  

  river 
  would 
  prevent 
  the 
  broken 
  ice 
  from 
  passing 
  rapidly 
  away, 
  

   and 
  (3) 
  that 
  floods 
  frequently 
  come 
  with 
  little 
  warning, 
  means 
  

   that 
  to 
  certainly 
  prevent 
  ice 
  dams 
  the 
  ice 
  must 
  be 
  continually 
  

   broken 
  during 
  these 
  months, 
  a 
  condition 
  involving 
  heavy 
  cost 
  for 
  

   furnishing 
  and 
  operating 
  powerful 
  ice-breaking 
  steamers. 
  More- 
  

   over, 
  when 
  we 
  consider 
  that 
  ice 
  dams 
  sometimes 
  obstruct 
  the 
  river 
  

   for 
  several 
  miles 
  in 
  extent, 
  the 
  impracticability 
  of 
  removing 
  them 
  

   by 
  mechanical 
  means 
  seems 
  sufficiently 
  obvious. 
  

  

  While 
  it 
  is 
  doubtless 
  possible 
  to 
  mitigate 
  floods 
  in 
  this 
  section 
  

   of 
  the 
  river 
  by 
  isolating 
  the 
  flooded 
  districts 
  by 
  dykes 
  or 
  levees, 
  

   which 
  would 
  necessitate 
  intercepting 
  sewers, 
  as 
  well 
  as 
  the 
  pump- 
  

   ing 
  of 
  the 
  surface 
  and 
  sewer 
  drainage 
  whenever 
  there 
  is 
  a 
  slight 
  

   freshet 
  in 
  the 
  river, 
  nevertheless 
  the 
  most 
  rational 
  treatment 
  is 
  

   believed 
  to 
  be 
  by 
  storage 
  of 
  the 
  flood-flow 
  in 
  the 
  upper 
  tributaries 
  

   of 
  the 
  stream. 
  

  

  The 
  opinion 
  has 
  been 
  expressed 
  that 
  storage 
  should 
  be 
  devel- 
  

   oped 
  proportionate 
  to 
  the 
  catchment 
  area 
  on 
  the 
  several 
  tributaries 
  

   of 
  the 
  Hudson 
  above 
  Troy, 
  and 
  while 
  this 
  is 
  theoretically 
  true, 
  

   the 
  writer 
  imagines 
  that 
  the 
  question 
  of 
  cost 
  will 
  finally 
  come 
  in, 
  

   very 
  greatly 
  modifying 
  any 
  purely 
  theoretical 
  deductions 
  based 
  

   on 
  this 
  view. 
  To 
  show 
  how 
  material 
  an 
  element 
  in 
  the 
  problem 
  

   cost 
  may 
  become, 
  it 
  may 
  be 
  mentioned 
  that 
  reservoirs 
  have 
  been 
  

   at 
  various 
  times 
  considered 
  costing 
  from 
  about 
  $20 
  per 
  million 
  

   cubic 
  feet 
  stored, 
  to 
  as 
  high 
  as 
  $200 
  or 
  $300 
  per 
  million 
  cubic 
  feet. 
  

   The 
  cost 
  of 
  such 
  reservoirs 
  as 
  compared 
  with 
  the 
  cost 
  of 
  reservoirs 
  

   for 
  municipal 
  purposes, 
  even 
  at 
  these 
  prices, 
  is 
  very 
  low, 
  the 
  cost 
  

   per 
  million 
  gallons 
  frequently 
  rising 
  higher 
  than 
  the 
  cost 
  per 
  

   million 
  cubic 
  feet 
  here 
  proposed. 
  But 
  nobody 
  is 
  likely 
  to 
  expend 
  

   a 
  large 
  amount 
  of 
  money 
  in 
  order 
  to 
  meet 
  the 
  theoretical 
  require- 
  

   ment 
  of 
  equal 
  storage 
  in 
  all 
  parts 
  of 
  a 
  catchment 
  area 
  when 
  con- 
  

   siderably 
  less 
  money 
  will 
  build 
  a 
  storage 
  reservoir 
  of 
  equal 
  

   capacity 
  elsewhere. 
  Practically, 
  therefore, 
  it 
  is 
  impossible 
  to 
  reg- 
  

   ulate 
  as 
  large 
  a 
  catchment 
  as 
  that 
  of 
  the 
  Hudson 
  river 
  to 
  anything 
  

   like 
  a 
  uniform 
  flow 
  throughout 
  all 
  of 
  its 
  tributaries. 
  The 
  mere 
  

   matter 
  of 
  cost 
  alone 
  will 
  militate 
  against 
  such 
  a 
  conclusion. 
  In 
  

   a 
  few 
  words 
  the 
  conditions 
  are 
  that 
  in 
  the 
  upper 
  Hudson, 
  above 
  

   Glens 
  Falls, 
  very 
  extensive 
  storage 
  reservoirs 
  may 
  be 
  constructed, 
  

   either 
  on 
  the 
  main 
  river 
  or 
  its 
  chief 
  tributaries, 
  Sacandaga, 
  

   Schroon 
  and 
  Cedar 
  rivers, 
  which 
  were 
  estimated 
  in 
  1895, 
  for 
  the 
  

   whole 
  system, 
  to 
  cost 
  something 
  like 
  $60 
  per 
  million 
  cubic 
  feet 
  

  

  