PLANE OF REFERENCE
==================

On waters of Vuoksi Water Course three reference datums are used as follows:

(1) High water during navigation season (HWnav) is used for vertical 
    clearences;
(2) Low water during navigation season (NWnav) is used for depth related 
    information, e.g. soundings and fairway depths;
(3) Mean sea level (MSL) is used for height countours.

The heights HWnav and NWnav in different lake basins based on reference
level NN:

Lappeenranta to Varkaus, Pilppa Canal and Joensuu
HWnav: NN+76.60 m 
NWnav: NN+75.10 m

Varkaus to Konnus Canal
HWnav: NN+81.40 m
NWnav: NN+81.10 m

Konnus Canal to Kuopio
Kuopio to Karvio and Taivallahti Canals
HWnav: NN+82.30 m
NWnav: NN+81.25 m 

Karvio Canal to Kerma Canal
HWnav: NN+80.50 m
NWnav: NN+79.45 m

Kerma Canal to Vihovuonne Canal
HWnav: NN+78.20 m
NWnav: NN+77.05 m

Vihovuonne Canal to Pilppa Canal
HWnav: NN+77.00 m
NWnav: NN+76.05 m

Taivallahti Canal to Kaavi
HWnav: NN+101.05 m
NWnav: NN+100.40 m


INFORMATION ON CURRENT WATER LEVEL
----------------------------------

Automatic water gauges

Lauritsala, tel. +358 5 4524696 (Zero at NN+70.00 m)
Kallavesi, tel. +358 17 2631646 (Zero at NN+80.37 m)

Water scales

Lappeenranta to Varkaus, Pilppa Canal and Joensuu
 Savonlinna lower, NWnav at 0 cm
 Savonlinna upper, NWnav at 21 cm 
 Oravi, NWnav at 103 cm
 Taipale lower, NWnav at 216 cm
 Pilppa lower, NWnav at 235 cm
 Puhos, NWnav at 20 cm
 Tikka, NWnav at 402 cm
 Joensuu lower, NWnav at 140 cm

Varkaus to Konnus Canal
 Taipale upper, NWnav at 339 cm
 Konnus lower, NWnav at 267 cm

Konnus Canal to Kuopio
Kuopio to Karvio and Taivallahti Canals
 Konnus upper, NWnav at 231 cm
 Kallavesi, NWnav at 88 cm
 Karvio upper, NWnav at 257 cm
 Varistaipale lowerm NWnav at 261 cm

Karvio Canal to Kerma Canal
 Karvio lower, NWnav at 198 cm
 Kerma upper, NWnav at 200 cm

Kerma Canal to Vihovuonne Canal
 Kerma lower, NWnav at 225 cm
 Vihovuonne upper, NWnav at 225 cm

Vihovuonne Canal to Pilppa Canal
 Vihovuonne lower, NWnav at 235 cm
 Pilppa upper, NWnav at 228 cm

Taivallahti Canal to Kaavi
 Taivallahti upper, NWnav at 202 cm

Finnish Maritime Administration
Hydrographic Department 2008