﻿HYDROLOGY 
  OF 
  NEW 
  YORK 
  515 
  

  

  the 
  Atlantic 
  coast 
  region 
  than 
  in 
  the 
  region 
  of 
  the 
  Central 
  

   Lakes. 
  

  

  The 
  preceding 
  mean 
  rainfalls 
  are 
  for 
  a 
  period 
  of 
  12 
  years 
  only, 
  

   which 
  is 
  not 
  long 
  enough 
  for 
  perfectly 
  safe 
  averages. 
  Moreover, 
  

   while 
  these 
  12 
  years 
  have 
  included 
  the 
  minimums 
  of 
  1895 
  and 
  

   1899, 
  these 
  minimums 
  were 
  not 
  as 
  well 
  denned 
  on 
  some 
  of 
  the 
  

   plateaus 
  as 
  on 
  others. 
  

  

  Since 
  the 
  precipitation 
  of 
  the 
  storage 
  period 
  largely 
  determines 
  

   the 
  runoff 
  of 
  that 
  period, 
  let 
  us 
  for 
  a 
  moment 
  consider 
  the 
  relation 
  

   between 
  precipitation 
  in 
  the 
  storage 
  period 
  of 
  the 
  Atlantic 
  coast 
  

   and 
  Central 
  Lakes 
  regions. 
  The 
  minimum 
  precipitation 
  in 
  the 
  

   storage 
  period 
  of 
  the 
  Atlantic 
  coast 
  region 
  for 
  the 
  12-year 
  period 
  

   included 
  in 
  the 
  tables 
  was 
  for 
  the 
  year 
  1896, 
  and 
  amounted 
  to 
  

   19.70 
  inches. 
  The 
  minimum 
  precipitation 
  of 
  the 
  Central 
  Lakes 
  

   region 
  for 
  the 
  same 
  period 
  was 
  in 
  1895 
  and 
  amounted 
  to 
  11.26 
  

   inches, 
  a 
  difference 
  of 
  8.44 
  inches 
  in 
  the 
  storage 
  period 
  alone. 
  

  

  The 
  yearly 
  minimum 
  precipitation 
  of 
  the 
  Atlantic 
  coast 
  region 
  

   for 
  the 
  period 
  considered 
  was 
  in 
  1895 
  and 
  amounted 
  to 
  40.77 
  

   inches. 
  The 
  yearly 
  miinimum 
  precipitation 
  of 
  the 
  Central 
  Lakes 
  

   region 
  was 
  also 
  in 
  1895 
  and 
  amounted 
  to 
  27.31 
  inches, 
  a 
  difference 
  

   of 
  13.46 
  inches. 
  The 
  proposition 
  that 
  there 
  was 
  over 
  10 
  inches 
  

   more 
  runoff 
  in 
  the 
  Atlantic 
  coast 
  region 
  in 
  1895 
  than 
  in 
  the 
  

   Central 
  Lakes 
  region 
  is 
  therefore 
  abundantly 
  established. 
  In 
  the 
  

   same 
  way 
  a 
  comparison 
  of 
  the 
  balance 
  of 
  the 
  regions 
  will 
  show 
  

   in 
  a 
  general 
  way 
  the 
  runoff 
  that 
  may 
  be 
  expected 
  in 
  any 
  given 
  year. 
  

  

  Taking 
  into 
  account 
  in 
  a 
  broad 
  way 
  these 
  several 
  precipitation 
  

   areas, 
  we 
  may 
  say 
  that 
  in 
  the 
  minimum 
  year 
  the 
  following 
  quan- 
  

   tities 
  of 
  water 
  can 
  be 
  stored, 
  the 
  statement 
  being 
  made 
  without 
  

   reference 
  to 
  the 
  economic 
  conditions 
  involved 
  in 
  considering 
  the 
  

   area 
  of 
  catchment, 
  topography, 
  cost, 
  etc. 
  The 
  statement 
  also 
  

   involves 
  conclusions 
  based 
  on 
  consideration 
  of 
  all 
  the 
  circum- 
  

   stances, 
  which 
  are 
  much 
  too 
  extensive 
  to 
  again 
  give 
  in 
  detail 
  but 
  

   which 
  are 
  given 
  in 
  different 
  parts 
  of 
  this 
  report 
  • 
  

  

  1) 
  On 
  the 
  western 
  plateau, 
  from 
  6 
  to 
  7 
  inches 
  may 
  be 
  stored 
  in 
  

   the 
  minimum 
  year. 
  

  

  2) 
  On 
  the 
  eastern 
  plateau, 
  7 
  to 
  10 
  inches. 
  

  

  3) 
  On 
  the 
  northern 
  plateau, 
  10 
  to 
  12 
  inches. 
  

  

  4) 
  In 
  the 
  Atlantic 
  coast 
  region, 
  13 
  to 
  15 
  inches. 
  

  

  