MSDI Data: Hydrography
framework hydrography data includes surface water features – lakes, rivers,
wetlands, and watersheds, structured to reference data related to those
features. Referenced data include stream flow measured at gage locations; trout
stream designations; point discharger locations; or water quality, water levels,
or zoning as lake descriptors. Surface water features need the following
- Good spatial representation
- Stable and consistent identification codes tied to established state and
- Vertical integration among river, lake, wetland, and watershed features if
maintained as separate GIS layers
- For rivers, the ability to identify a location for a stream-related
characteristic, feature or activity through an ‘addressing’ scheme
- For rivers, connectivity through lakes, wetlands, and two-dimensional
Changes in hydrology and data capture improvements necessitate periodic
updates to these data. The current hydrography data plan focuses on “framework”
data. Geology, hydrogeology, aquifers, wells, ground water extent or quality
data will be addressed at a later time.
The Hydrography Committee of the Governor's Council on Geographic Information
serves as the MSDI Cadastral data workgroup. It's members are responsible for
developing and maintaining a strategic plan for meeting the state's needs for
- Maps of rivers, lakes, wetlands, and watersheds at various scales as
- Maps of water characteristics, such as impaired waters maps or trout
- Analysis of relationships among water-related features, such as discharges
into rivers in relation to surface water intakes
- Analysis of upstream/downstream relationships among river features,
characteristics, or activities, especially useful for assessing impacts of
hazardous spills or discharges on downstream water users
- Engineering applications, such as hydraulic analysis for bridge and road
construction and inputs to engineering models
Through coordination and significant collaborative investments by many
agencies, Minnesota has developed several statewide hydrography datasets
consistent with federal standards.
- DNR 24K Streams and Lakes. This statewide dataset represents basic
lines for river and lake features. DNR derived rivers from the Mn/DOT base map
data and lakes from the National Wetland Inventory. Development is completed.
- National Hydrography Dataset, High-Resolution. With production
spearheaded by the MPCA, the High-Resolution National Hydrography Dataset (NHD)
is 95 percent completed for the state. Using the DNR 1:24,000 streams and
lakes as input and software provided by federal agencies, the NHD offers
consistency with national standards.
- Wetlands. The National Wetlands Inventory for Minnesota was
completed in the early 1990s. The data update issue is being studied by the
Comprehensive Wetland Assessment, Monitoring and Mapping Strategy Project and
the U.S. Fish and Wildlife Service.
- Watersheds. The last statewide watershed layer was completed by the
DNR in 1999. The DNR has completed 30 percent of a project to improve
delineation of watersheds and add delineations for all lakes greater than 100
acres. Additional work is needed to bring the DNR’s watershed data into full
compliance with the federal Watershed Boundary Dataset .
- Hydrographic Events. The statewide 1:24,000 NHD layer provides the
consistent, networked data that supports mapping of hydrographic events. An
MPCA project to reference key data about rivers and lakes to the NHD will
begin in fall 2004.
A draft MSDI Data Plan for hydrography was prepared in March 2003 and revised
in February 2004. The plan will be completed by the summer of 2005.
Data development has been dependent largely on short-term grants. There is no
long-term funding plan for data completion and update for all hydrography
- Scale. Statewide databases are produced at a 1:24,000 scale. Larger
scale sources are needed for some state and local government applications,
engineering applications, and some legal designations. Some uses that cross
state boundaries require smaller scales.
- Roles and responsibilities. With a few exceptions, roles and
responsibilities have not been defined for updating key hydrography data
layers or for maintaining vertical integrity among the various data sets.
- Long-term funding. Long-term funding sources for completing and
maintaining these databases have not been identified or secured.
- Data standards. The Hydrography Committee has established standards
for naming and feature identification of lakes, rivers, and watersheds, and
will complete a hydrographic event standard next year.
To learn more about the strategic plan for meeting hydrography data needs within
Minnesota, contact one of the chairs of the
Hydrography Committee of the MN Governor's Council on Geographic Information.