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Guideline S.1 Identification and Avoidance of Critical Sites


To ensure that appropriate project sites are chosen, and to minimize the development footprint on portions of sites whose natural features and functions are particularly valuable to the larger community. To ensure that development is minimized on sites where soil, water, and flora/fauna indicators are in a fragile condition because of surrounding development or because of the site’s natural state. Knowledge of critical site conditions help determine actions to be taken under S.4 Sustainable Vegetation Design.

Required Performance Criteria

Guidelines apply to all projects designated New Buildings.

Avoid selecting sites that meets any one of the following Critical Site Criteria:

  1. Land of national, state, regional, or local natural resource and biological/ecological significance as identified in national, state, regional, or local natural resources inventories, assessments and biological surveys and land within 150 feet of this type of these areas that functions as a buffer zone.
  2. Prime farmland and farmed wetland as defined by state statute rules and identified in County Soil Surveys and/or County/regional farmland and natural areas conservation/preservation programs.
  3. Land with elevation lower than 5 feet above the elevation of the 100-year flood (as defined by the local watershed district, watershed management organization, or joint powers organization) and land that acts as a buffer zone within 50 feet of these areas.
  4. Land that provides habitat for any animal or plant species on the federal or state threatened or endangered list, and/or land that provides habitat for any rare animal or plant species using the Minnesota County Biological Survey (CBS), and land that acts as a buffer zone within 300 feet of these areas. If rare, threatened, or endangered species are present on maps of a subject site, contact the CBS for exact coordinates of the said species.
  5. Land that was public parkland prior to acquisition for a project, unless land of equal or greater value as parkland is accepted in trade by the public landowner (Park Authority projects are exempt).
  6. Land under a conservation easement.

If the site does not completely avoid the conditions in S.1A, S.1C, or S.1D, there are site management implications in S.4D, S.4E, and S.4F, respectively.

Implementation in the Design Process:

In the predesign and early design of the project, determine ideal spatial needs for existing or new development. Identify critical sites for preservation or restoration on the project site as defined by the B3 Guidelines, and determine the type of buildings and related infrastructure that will be required for the developed areas and their spatial requirements. After a site has been selected, create potential spatial footprints that preserve any critical sites identified during the predesign phase

Through the design process, refine site plans and details that preserve, protect, and/or enhance critical sites within the project area.

In the construction documents, construction administration and buyout of the project hold a preconstruction meeting to identify requirements for protection/preservation of critical sites during and after the construction process. Consider easements for critical sites that will preserve those sites beyond the life of the project.

Comprehensive County “Critical Natural Resources” map and assessments such as Minnesota County Biological Surveys, DNR Natural Resources Inventory, and Assessment (NRI/A) (in 7 county Metro Area), local NRI/A’s and other national, state, or county databases and maps not listed here may aid in identifying habitat with identified or potential threatened or endangered flora/fauna. A municipality’s current Comprehensive Plan may help identifying areas designate as parkland.


  • S.1A through S.1F: Identification of any critical site conditions.


  • S.1A through S.1F: Identification of any critical site conditions onsite and any impingement, existing, and proposed conditions for critical site concerns, including restored lands as applicable.

Final Design:

  • S.1A through S.1F: Identification of any critical site conditions and impingement on critical site conditions, existing and updated proposed conditions for critical site concerns, including restored lands as applicable.

Public Land Survey Notes are available at the University of Minnesota, Twin Cities Campus, Wilson Library – range, township, and section information is needed on the subject site.

Marshner’s Land Cover Map of Minnesota:,

National Wetland Inventory:

Farmland Information Center:

The Minnesota Board of Water and Soil Resource (BWSR):

Minnesota Land Trust

Minnesota Rules referencing the Board of Soil and Water Resources, Chapters 8400-8420:

Soil and Water Conservation Society

American Land Title Association/American Congress of Surveying and Mapping (ALTA) Survey: