﻿HYDROLOGY 
  OF 
  NEW 
  YORK 
  337 
  

  

  Geologically, 
  the 
  catchment 
  area 
  of 
  the 
  Genesee 
  river 
  above 
  

   Mount 
  Morris 
  lies 
  in 
  the 
  shales, 
  sandstones, 
  etc. 
  of 
  the 
  Portage 
  

   and 
  Chemung 
  groups. 
  Its 
  extreme 
  headwaters 
  south 
  of 
  the 
  

   Pennsylvania 
  line 
  issue 
  from 
  the 
  Carboniferous. 
  Generally 
  the 
  

   soils 
  throughout 
  the 
  whole 
  basin 
  are 
  heavy 
  and 
  tenacious, 
  in- 
  

   clining 
  to 
  clay. 
  Their 
  capacity 
  for 
  absorbing 
  and 
  retaining 
  

   water 
  must 
  therefore 
  be 
  considered 
  small. 
  

  

  Discharge 
  measurements 
  of 
  Oatka 
  creek. 
  The 
  measurements 
  

   of 
  Oatka 
  creek, 
  referred 
  to 
  in 
  the 
  preceding, 
  were 
  made 
  at 
  the 
  

   milldam 
  in 
  the 
  south 
  part 
  of 
  the 
  village 
  of 
  Warsaw, 
  in 
  Wyoming 
  

   county. 
  The 
  dam 
  was 
  new, 
  practically 
  tight, 
  and 
  well 
  adapted 
  

   for 
  securing 
  accurate 
  results. 
  Measurements 
  were 
  also 
  made 
  

   of 
  the 
  outflow 
  of 
  the 
  head 
  raceway 
  leading 
  from 
  the 
  dam 
  for 
  

   different 
  elevations 
  of 
  water 
  on 
  the 
  dam, 
  and 
  a 
  curve 
  prepared 
  

   from 
  which 
  the 
  discharge 
  of 
  the 
  raceway 
  was 
  read 
  off 
  and 
  added 
  

   to 
  the 
  discharge 
  over 
  the 
  dam. 
  

  

  The 
  catchment 
  area 
  of 
  Oatka 
  creek 
  above 
  Warsaw 
  includes 
  

   27.5 
  square 
  miles 
  of 
  rolling, 
  semi-mountainous 
  country. 
  The 
  

   valley 
  of 
  the 
  creek 
  is 
  deep 
  cut, 
  with 
  numerous 
  springs 
  at 
  the 
  

   headwaters. 
  The 
  catchment 
  is 
  mostly 
  deforested 
  and 
  in 
  a 
  high 
  

   state 
  of 
  cultivation, 
  the 
  soil 
  inclining 
  to 
  clay 
  for 
  a 
  considerable 
  

   portion. 
  Geologically 
  the 
  stream 
  lies 
  in 
  the 
  rocks 
  of 
  the 
  Port- 
  

   age 
  formation, 
  as 
  developed 
  in 
  western 
  New 
  York. 
  The 
  runoff 
  

   from 
  this 
  area 
  may 
  be 
  taken 
  as 
  typical 
  of 
  many 
  small 
  streams 
  

   in 
  western 
  New 
  York. 
  

  

  Discharge 
  measurements 
  of 
  Hemlock 
  lake. 
  Measurements 
  of 
  

   the 
  runoff 
  of 
  the 
  Hemlock 
  lake 
  area 
  for 
  the 
  water 
  years 
  1880 
  to 
  

   1884, 
  inclusive, 
  were 
  made 
  by 
  the 
  Kochester 
  Waterworks. 
  Hem- 
  

   lock 
  lake 
  lies 
  at 
  an 
  elevation 
  of 
  896 
  feet 
  above 
  tide, 
  and 
  has 
  a 
  

   length 
  of 
  6.5 
  miles, 
  with 
  an 
  average 
  width 
  of 
  about 
  0.5 
  of 
  a 
  mile. 
  

   The 
  area 
  of 
  the 
  surface 
  at 
  low 
  water 
  is 
  1828 
  acres. 
  The 
  total 
  

   catchment, 
  including 
  the 
  area 
  'of 
  the 
  lake, 
  is 
  27,554 
  acres, 
  or 
  

   about 
  43 
  square 
  miles. 
  The 
  shores 
  are 
  bold, 
  and 
  on 
  the 
  east 
  side 
  

   rise 
  to 
  a 
  hight 
  of 
  several 
  hundred 
  feet 
  above 
  the 
  lake 
  in 
  a 
  dis- 
  

   tance 
  of 
  2 
  or 
  3 
  miles. 
  At 
  the 
  head 
  of 
  the 
  lake 
  there 
  is 
  a 
  swamp 
  

   of 
  118 
  acres, 
  partially 
  covered 
  at 
  high 
  water. 
  

  

  The 
  outflow 
  of 
  the 
  lake 
  during 
  the 
  period 
  covered 
  by 
  the 
  

   measurements 
  included 
  in 
  the 
  following 
  table 
  may 
  be 
  considered 
  

   as 
  having 
  taken 
  place 
  at 
  three 
  points: 
  (1) 
  At 
  the 
  natural 
  outlet 
  

  

  