Canada's National Hydro Network (NHN) Standard is now official. In August, the Canadian Council on Geomatics (CCOG) approved the "National Hydro Network, Canada, Level 1, Edition 1.0" Standard, in accordance with CCOG resolution F03-05 on GeoBase Data Standard Maintenance.

The NHN is a digital geospatial data set describing Canada's surface waters. The NHN standard includes a data model, specifications, and a catalogue that describes the entities to be included and their attributes. It synthesizes elements of hydrography and hydrology so as to be compatible with several different types of applications including both cartographic representations and the spatial analysis of data. Both are important for sustainable water management.

Adoption of the NHN standard comes after many years work and following extensive consultations, including meetings with data producers and users as well as two national consultations that brought together federal, provincial, and territorial stakeholders.

The adoption of the NHN standard is an important step for sustainable water management in Canada. Many experts capture digital geospatial data relating to water in our country, but the integration of this data is difficult since the data geometry and models used are different. In addition, this water-related geospatial data must be manipulated and incorporated into modern decision-making systems such as GIS in order to be most useful. This process is costly and time-consuming and risks the integrity of the data itself. The NHN will resolve these difficulties by establishing a common standard so that specialists and decision-makers can use the same water-related data.

The NHN will:

• Prevent the duplication of work
• Allow information sharing, analysis and decision-making among groups, as these groups will all be working from the same set of data
• Improve the reliability and accuracy of data, as updates will be available to all via the Internet
• Provide for the integration of water-related data into decision-making tools and systems, as the NHN data will be GIS-ready, standardized against a national model, using a common vocabulary, in a single data base

The NHN standard was developed in alignment with the GeoBase objective of making quality geospatial data available to Canadians. In addition, the NHN will be developed according to GeoBase principles and best practices. Thus, NHN data will be captured only once, as close to the source as possible, and from the best available data. It will also be distributed without user restrictions to the Canadian community. The NHN is a flexible model that allows partners and end-users to integrate their own data into the NHN's common model and vocabulary.

Partners are already producing data according to the newly accepted NHN standard. In fact, the provinces of Nova Scotia and British Columbia are already producing data using their provincial topographic data bases. Both provinces foresee the completion of data production for the whole province by the spring of 2005. NRCan has also begun data production for parts of Manitoba and Saskat-chewan using data from the National Topographic Data Base that have already been geometrically corrected according to GeoBase Landsat-7 ortho-images.

The GSDNR Communicator: Fall 2004