Frequently asked questions about rivers and streams

What is a watershed?

A watershed is a topographically delineated area that is drained by a stream system. It is the total land area above some point on a stream or river. It is sometimes referred to as a drainage basin. The watershed is a hydrologic unit that has been described and used as a physical-biologic unit and a socioeconomic-political unit for planning and management of natural resources.

     Learn more about watersheds.

What are some common hydrologic terms and definitions?

See Hydrologic Terms.

What constitutes a "stream" versus a "river"?

"Stream" is a generic word that is used to refer to either a creek or a river, although there are no universally accepted definitions that clearly differentiate between the two. It is generally accepted that a river is larger than a creek, however, it is possible to find a few named rivers that are tributary to named creeks across the United States. These few cases are a function of local name use or preference, and have nothing to do with the size of the respective streams.

What is the definition of ordinary high water level (OHWL) and why is it important?

The ordinary high water level (OHWL) is a reference point that defines the DNR's regulatory authority over development projects that are proposed to alter the course, current, or cross section of public waters and public waters wetlands. For lakes and wetlands, the OHWL is the highest water level that has been maintained for a sufficient period of time to leave evidence upon the landscape. The OHWL is commonly that point where the natural vegetation changes from predominately aquatic to predominantly terrestrial. For watercourses (rivers and streams), the OHWL is the elevation of the top of the bank of the channel. For reservoirs and flowages, the OHWL is the operating elevation of the normal summer pool. The OHWL is also used by local units of government as a reference point from which to determine structure setbacks from water bodies and watercourses.

     Learn more about ordinary high water levels.

What is a wild and scenic river?

A wild and scenic river is a river that has been designated under the Minnesota Wild and Scenic Rivers Act or the National Wild and Scenic River Act. These designated rivers are the following:

What can I do to prevent erosion?

Two general methods are available to prevent your lakeshore from eroding: hard armoring and soft armoring. The most common hard-armor technique is riprap, which consists of placing large rocks in the water and up the slope of the eroding shoreline. Riprap is commonly used to control erosion along streambanks and lakeshores where vegetation is not sufficient to prevent erosion caused by high water or wave action. It is expensive to install and is often installed incorrectly. If installed properly, however, riprap normally provides good protection from the impact of waves, stream velocities and ice. Some believe that riprap is overused and unsightly and that Minnesota lakes have lost much of their natural shoreline to riprap.

In contrast to hard-armor techniques, soft-armor methods use organic and inorganic materials combined with plants to create a living barrier of protection. Bioengineering, a soft-armor method, provides erosion control through the use of live vegetation. Bioengineering can be used in addition to or in place of hard armor such as rock riprap. It creates a more natural, environmentally friendly shoreline that includes additional benefits to erosion control, such as habitat enhancement. Specific to rivers and streams, DNR Waters published a booklet in 1991 called ?Streambank Erosion: Gaining A Greater Understanding, August 1991?, which is available in limited quantities from our Stream Hydrology Program personnel in St. Paul. A DNR public waters work permit (application available under DNR Waters Forms) may be required for both soft and hard armoring methods.

How do I name a river or stream?

Naming a river or stream in Minnesota, or changing the name, is guided by Minnesota Statue 83A.04 - 83A.07.

The process begins at the county where the river or stream is located. Fifteen or more voters registered in that county must petition the county board of commissioners for a public hearing. If the county board agrees on the proposed name, the board adopts a resolution in support of the name.

The resolution is forwarded to the Department of Natural Resources Commissioner for approval. The Commissioner will not approve a name that commemorates or may be seen to commemorate, a living person.

Approved names are submitted to the U.S. Board on Geographic Names for federal approval and use.

Also see: Naming Geographic Features