﻿HYDROLOGY 
  OP 
  NEW 
  YORK 
  187 
  

  

  it 
  may 
  be 
  fixed 
  at 
  f 
  100 
  per 
  acre. 
  At 
  this 
  rate 
  the 
  catchment 
  area 
  

   of 
  339 
  square 
  miles 
  would 
  cost 
  $21,696,000. 
  The 
  planting 
  out 
  of 
  

   trees 
  could 
  hardly 
  cost 
  less 
  than 
  $20 
  per 
  acre 
  additional, 
  but 
  in 
  

   order 
  to 
  make 
  the 
  estimate 
  as 
  reasonable 
  as 
  possible 
  we 
  will 
  take 
  

   it 
  at 
  $10 
  per 
  acre, 
  which 
  makes 
  an 
  additional 
  sum 
  of 
  $2,169,900, 
  

   or 
  a 
  total 
  of 
  $23,865,900. 
  

  

  If 
  we 
  assume 
  the. 
  annual 
  interest 
  at 
  3 
  per 
  cent, 
  and 
  place 
  this 
  

   sum 
  at 
  compound 
  interest 
  for 
  120 
  years, 
  we 
  have 
  at 
  the 
  end 
  of 
  

   that 
  time 
  the 
  sum 
  of 
  $779,510,000. 
  The 
  present 
  safe 
  yield 
  of 
  the 
  

   Croton 
  catchment, 
  with 
  all 
  available 
  storage, 
  is 
  about 
  280,000,000 
  

   gallons 
  per 
  day. 
  We 
  would 
  pay, 
  therefore, 
  this 
  large 
  sum 
  for, 
  

   perhaps, 
  75,000,000 
  gallons 
  additional 
  per 
  d&y 
  at 
  the 
  end 
  of 
  120 
  

   years. 
  ' 
  It 
  is 
  true 
  there 
  would 
  be 
  some 
  increase 
  in 
  water 
  supply 
  

   after 
  about 
  '30 
  years, 
  and 
  the 
  supply 
  might 
  be 
  expected 
  to 
  go 
  on 
  

   increasing 
  until 
  the 
  average 
  increase 
  of 
  yield 
  was 
  attained 
  in 
  120 
  

   years. 
  But 
  the 
  increase 
  in 
  water 
  supply 
  would 
  not 
  be 
  at 
  all 
  

   commensurate 
  with 
  the 
  increase 
  of 
  capitalization. 
  It 
  is 
  very 
  

   evident 
  that 
  an 
  expenditure 
  of 
  this 
  sum 
  of 
  money 
  would 
  procure 
  

   a 
  far 
  greater 
  quantity 
  of 
  water 
  from 
  other 
  sources. 
  Hence 
  it 
  

   does 
  not 
  seem 
  expedient 
  to 
  suggest 
  the 
  forestation 
  of 
  the 
  Croton 
  

   catchment 
  area 
  as 
  a 
  method 
  of 
  obtaining 
  an 
  increased 
  water 
  

   supply. 
  As 
  to 
  whether 
  it 
  is 
  desirable 
  to 
  reforest 
  this 
  area 
  as 
  a 
  

   forestry 
  investment 
  is 
  another 
  question 
  which 
  is 
  not 
  discussed 
  

   here. 
  

  

  Another 
  objection 
  to 
  the 
  forestation 
  of 
  the 
  Croton 
  catchment 
  

   as 
  a 
  remedy 
  for 
  the 
  water 
  difficulties 
  of 
  New 
  York 
  city 
  may 
  be 
  

   found 
  in 
  the 
  fact 
  that 
  a 
  considerably 
  increased 
  water 
  supply 
  is 
  

   wanted 
  at 
  once 
  ; 
  it 
  is 
  entirely 
  out 
  of 
  the 
  question 
  to 
  wait 
  120 
  years 
  

   for 
  such 
  increased 
  supply. 
  

  

  As 
  a 
  broad 
  proposition, 
  however, 
  catchment 
  areas 
  from 
  which 
  

   municipal 
  water 
  supplies 
  are 
  drawn 
  should 
  be 
  in 
  forests, 
  and 
  

   undoubtedly 
  as 
  time 
  goes 
  on 
  this 
  condition 
  will 
  be 
  more 
  and 
  more 
  

   attained. 
  Already 
  various 
  European 
  and 
  American 
  municipali- 
  

   ties 
  have 
  recognized 
  the 
  advisability 
  of 
  owning 
  the 
  catchments 
  

   from 
  which 
  their 
  municipal 
  water 
  supplies 
  are 
  drawn. 
  From 
  

   this 
  point 
  of 
  view 
  it 
  is 
  desirable 
  to 
  reforest 
  the 
  Croton 
  catchment. 
  

  

  