396 
On  River  Conservancy, 
and  locks  and  weirs  constructed  for  holding  the  water ; but 
the  greater  facilities  afforded  by  railways  have  almost  entirely 
diverted  the  traffic.  The  proprietors  of  these  navigations  have 
suffered  seriously  by  the  loss  of  the  dues  ; and  although  unable  to 
fulfil  the  duties  belonging  to  a proper  maintenance  of  the  streams, 
they  still  cling  to  the  remnant  of  traffic  left,  and  would  offer 
great  obstruction  to  any  scheme  of  improvement  which  did  not 
offer  to  reimburse  them  for  their  lost  rights.  So  long  as  these 
navigations  were  maintained  in  order,  the  shoals  dredged  out, 
the  weeds  cut  or  kept  down  by  the  traffic  of  the  boats,  and  the 
staunches  and  weirs  kept  in  good  order  and  properly  attended 
to,  the  rivers  were  in  a fair  condition  to  discharge  the  flood- 
waters  ; but  since  the  navigation  has  ceased,  there  are  no  funds 
to  maintain  the  works  in  an  efficient  condition,  or  to  alter  and 
improve  the  weirs  so  as  to  adapt  them  to  modern  requirements 
of  drainage.  In  some  cases  the  canals  have  been  entirely  aban- 
doned by  their  original  owners,  the  Acts  of  Parliament  obtained 
for  this  purpose  making  no  provision  for  restoring  the  rivers  to 
their  original  condition.  Thus,  on  the  Ivel,  a tributary  of  the  Ouse, 
the  navigation  Trust  created  in  the  reign  of  George  II.  was 
abolished  in  1876  ; the  works  have  been  all  abandoned,  the  locks 
and  weirs  allowed  to  go  to  ruin,  the  channel  has  diminished  one- 
half  in  width  and  one-half  in  depth,  and  the  bottom  is  gradually 
being  raised  to  the  level  of  the  land.  A miller,  to  protect  his 
supply  of  water,  has  placed  a solid  dam  across  the  stream,  and 
nobody  has  now  sufficient  power  over  the  river  to  prevent  him. 
In  like  manner  the  Lark,  another  canalised  river,  is  said  to  be 
almost  entirely  silted  up  since  the  navigation  ceased. 
Another  cause  of  floods  is  undoubtedly  to  be  traced  to  the 
condition  of  bridges.  In  many  cases  these  are  utterly  in- 
adequate to  take  the  water  in  times  of  flood,  and  form  a 
permanent  block  to  its  flow.  Even  where  the  arches  are  of 
sufficient  capacity,  they  have  often  been  allowed  to  become 
blocked  up,  and  otherwise  unsuited  for  the  free  flow  of  the 
water.  As  a rule,  the  duty  of  maintaining  bridges  over  public 
streams  devolves  on  the  county  ; but  this  duty  only  relates  to 
maintaining  the  roadway,  and  not  the  waterway,  and  there  is 
nobody  whose  duty  it  is  to  compel  the  removal  of  obstructions, 
or  to  undertake  to  raise  the  funds  and  carry  out  improvements 
necessary  to  render  many  of  the  older  bridges  adapted  to  the 
altered  condition  of  the  streams  and  rivers. 
Present  Condition  of  Legislation.  . 
The  ownership  in  the  bed  and  banks  of  a non-tidal  stream 
of  water  is  in  the  proprietors  of  the  adjacent  lands  up  to  the 
