PLANE OF REFERENCE
==================
 
In Saimaa Canal two planes of reference (datums) are used as follows:
(1) Low water (LW) is used for depth related information, e.g. soundings and 
    fairway depths, and heights of lights and other aids to navigation;
(2) High water (HW) is used for vertical clearences;
 
Both datums are based on water levels during sailing season and are equal to 
values NWnav and HWnav referred to in some publications. 
  
The heights LW and HW in different sections of the canal based on reference 
level N2000:
 
Pälli to Soskua
   LW: N2000+48.90 m
   HW: N2000+49.00 m
Soskua to Mustola
   LW: N2000+57.16 m
   HW: N2000+57.30 m
Mustola to Mälkiä
   LW: N2000+64.27 m
   HW: N2000+64.57 m
Mälkiä to Lauritsala
   LW: N2000+75.40 m 
   HW: N2000+76.85 m
  
Finnish Transport and Communications Agency
Hydrographic Office 2025