Vertical Control - Water Levels Subcommittee

Membership
Terms of Reference
Adopted 6 June 1995

1. Review existing International Great Lakes Datum (IGLD) and revise as appropriate. Issue informational materials and reports establishing bench mark elevations whenever IGLD is updated.
2. Review and update as necessary the apparent vertical, crustal and other movement rates between water level gauge sites in the Great Lakes-St. Lawrence River System, and report coordinated findings.
3. Review and coordinate methodologies for leveling water level gauges in the Great Lakes-St. Lawrence River System used in international coordination activities and conduct inspections according to coordinated procedures.
4. Review the permanent Great Lakes-St. Lawrence River System water level gauge network, and recommend relocations, additions or deletions to the network to meet the changing needs of the users.
5. Update and publish the coordinated histories of water level gauge sites in the Great Lakes-St. Lawrence River System.
6. Review and update the method for determining representative lake-wide water levels for each of the Great Lakes and Lake St. Clair and coordinate the historic statistics for these representative levels