Definition: As provided in a community's comprehensive plan, a primary set of tools for conserving and managing natural resources are land use regulations, such as zoning.
Subdivision Regulations
How a community subdivides land for development will have serious, and often unintentional and unnecessary, impacts on natural resource conservation. During subdivision, the community makes fundamental decisions on how much land development will consume, how much of it will be paved (made impervious to water infiltration), and whether opportunities for community trails, greenways, and open space are retained or lost forever.
Both the community's subdivision requirements and the landowner/developer's proposal on how to subdivide the land need to be based on appropriate natural resource information. By thoughtfully using natural resource information, the subdivision layout can be designed to:
- cost-effectively use natural systems to manage storm water,
- minimize the impact on forests, significant trees, natural grassland, wetland, etc, and
- conserve natural areas and corridors for the common good.
A community may require or allow the dedication of park land, utility or trail easements, storm water treatment areas, etc. as part of a subdivision. Decisions on requiring, allowing, or accepting donations of lands or easements through the subdivision process, must be consistent with the community priorities and their plans for parks, open space, trails, and storm water management. By accepting a dedication of land, the community usually assumes liability, maintenance, policing, and associated operating costs.
NRI Information Needed for Subdivision Decisions
For wise decisions on a subdivision to be made, a proposal for subdividing property needs to contain natural resource information including:
- topography (e.g. a map with 2' contours),
- aerial photography (e.g. recent digital ortho quad or color infrared),
- soils (e.g. a soil survey map) and their suitability for proposed type of development,
- water bodies (lakes, rivers, streams, and wetlands) on or adjacent to the site, and
- locations (map) of all existing vegetation and identification of significant vegetation and any rare plant and animal species.
Furthermore, for sound land dedication/easement decisions, the community must have their own assessment of the resources, their value, and implications for public land management.
Zoning Ordinances
Historically, zoning ordinances have been a mechanism for separating different land uses. Through zoning, rural communities can establish permanent agriculture or working forest
zones to reduce conversion of these highly productive lands to other uses. Now, communities may also apply zoning creatively through using planned unit development, mixed use zoning, overlay zones, incentive zoning, transfer of development rights, growth management, and other tools (some referenced below) that offer greater opportunities to efficiently use land while conserving resources. Also, through zoning, performance standards may be used to specify maximum or minimum thresholds for specific nuisances/elements with impacts (e.g. air and water pollution, traffic, noise, odors, runoff, septic system performance, etc.).
NRI Information Useful When Updating a Zoning Ordinance
When updating their zoning ordinance, the community can strengthen its effectiveness as a tool in conserving natural resources by addressing natural resource information questions such as:
- What natural resource-based community values should be recognized in the ordinances purpose statement?
- Does the zoning ordinance use current, science-based definitions of natural resources to be conserved (e.g. bluff, open space and/or green area, natural area, rare species, steep slope, etc.)?
- Do the general provisions of the zoning ordinance call for environmental considerations (e.g. landscaping or buffering, tree preservation, limits to earth moving and construction damage to soil or native vegetation, erosion and runoff controls)? If so, does the ordinance call for a review process and the natural resource information needed for it? (See section below on plan/design review.)
- Does the zoning ordinance incorporate performance standards, allow for, or give incentives for "low impact development" (i.e. development that minimizes storm water runoff through on site infiltration, reduced imperviousness, rain gardens etc.)?
Overlay Zones
An overlay zone or district allows special regulations within all or part of one or several zoning districts. Many communities use this tool to guide or limit development in floodplains, along shorelands, next to airports, in historic preservation districts, and so forth. A newer model is a Natural Area Overlay District which may be used to protect the most fragile natural areas in a community or assure compatible development along with conservation of other natural resources. [see the checklist on Natural Environmental Areas Overlay District Ordinance].
Natural Resource Information Critical for Overlay Zones
Establishment of an overlay zone inherently requires the community to adopt an accurate map of the areas/resources to be protected. This necessitates that a current natural resource inventory be used to identify all areas containing the resource to be protected that will fall within the overlay zone.
For example, when the City of Maple Grove identified forest protection as a community priority, they hired a consulting forester to inventory all of their forests. The city then enacted the Maple Grove Forest Tree Preservation District ordinance which has a mapped "T-zone". Any development proposed within the T-zone must go through a review process which requires a detailed tree inventory and tree preservation plan.
Planned Unit Development (PUD)
Communities can creatively plan development and conservation for a larger parcel through a Planned Unit Development (PUD) rather than a typical subdivision process. This is the mechanism by which some communities are implementing "Conservation Subdivisions" - in which contiguous open space and natural areas are preserved and development is efficiently clustered on the less vulnerable parts of the site. Permanent protection of the open spaces typically depends on a use of a conservation easement.
Natural Resource Information Needed to Guide PUD
Clearly, planning for any form of PUD needs to be based on detailed natural resource information to direct land conservation where needed most. The purpose of this resource assessment is to assure that the PUD design recognizes and accounts for all the site's resources and to assist the local unit in evaluating the proposal's impacts on those resources.
For example, in 1997, Washington County released their "Open Space Design Development: A Guide for Local Governments" that provides their development standards and outlines the procedure for developing a Open Space Design (OSD) development ordinance or adding provisions to an existing zoning ordinance. It requires applicants for a OSD submit a resource inventory with information on topography, soil , hydrology, vegetation, land use, land cover, and visual and cultural resources. It also outlines performance standards, including siting development to minimize fragmentation of open space and disturbance to woodlands and other natural features.
Plan/Design Review
Many communities require plans to be submitted for review and approval before a local permit, such as a building permit, is issued. The review of the plans is based on standards adopted by ordinance or less formal guidelines and administrative processes. To provide meaningful natural resource conservation, plan review must be authorized and designed to significantly influence fundamental ecological, land cover and water management issues. Also, applicants need to be provided with the standards/guidelines as early as possible. When well done, site plan review is an effective tool for minimizing localized environmental impact and achieving improved, and at times innovative, storm water management, conservation of native soil and vegetation, tree protection, shoreland or prairie restoration, retention of naturalized riparian corridors, pedestrian connections, etc
Natural Resource Information Needed in Plan Review
Applicants going through site plan review should be required to submit the existing and proposed natural resource information necessary for the community to adequately review the project, including before and after data including:
- topographic map with 2' contours,
- soils (and their protection during construction),
- storm water drainage,
- delineation of waterbodies,
- vegetation (and its protection/management during and after construction),
- pedestrian access and circulation,
- opportunities for linking to community greenways or conservation areas
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- if applicable, wildland fire risk
When a landscape plan is required for review and approval, information should be submitted on:
- soils and grading,
- native vegetation,
- exotic species control (if applicable),
- snow storage,
- maintenance, and
- how the landscape improvements enhance storm water infiltration and other community objectives.
Incentive Zoning
The premise of incentive zoning tools is that a community can gain qualities it wants - such as natural resource conservation, energy/resource efficiency, and/or affordable housing - in exchange for something the private developer would like - such as higher density. [see checklist on Conserving Natural Resources through Density Bonuses]
Natural Resource Information Needed for Incentive Zoning Decisions
Before offering developers incentives, the community needs to decide its conservation priorities. Information is needed that identifies and maps the community's most important types and locations of natural resources, its remaining natural areas, its proposed greenway and trail alignments, and other important opportunities
Also, the development proposal needs to supply enough information for the community to ascertain whether the proposal meets their criteria for offering an incentive. Basic submission requirements could be:
- a scaled map of site features including existing vegetation, water bodies, topography and soil, and
- descriptions or maps of natural areas on adjoining properties, site hydrology, proposed natural resource conservation strategies.
Transfer of Development Rights
Transfer of development rights (TDR) is an innovative way of regulating land use that involves shifting the location of development to the areas most suitable for it, while maintaining the community's overall number of housing units. TDR programs are enabled by a local or regional ordinance, which create 'sending areas'(to be preserved) and 'receiving areas', which have increased densities. Developers purchase the development rights from the sending area and use them to increase existing or planned densities in the receiving areas. TDR programs are complex and require knowledge of market forces, as well as significant administrative investments. Typically, they have been most successful in areas that have very limited open space opportunities and the community is collectively motivated to keep what open space is left.
Urban Growth Area/Boundaries
A local comprehensive plan may include policies on how the community would like to direct future development. An "urban growth area" is the land needed to accommodate projected residential, commercial, and/or industrial development over a specified period of time.
Basing Urban Growth Areas on Natural Resource Information
The best process of determining growth areas with an adequate urban land supply is to identify lands to be excluded before identifying developable lands. This involves using a natural resource-based planning process (as outlined above) in which lands are identified and eliminated from consideration which have physical constraints (e.g. unbuildable soils, steep slopes, and regulated wetlands), are needed for public purposes (e.g. utility corridors and green infrastructure including storm water management and recreation open space), and which have economically and socially critical resources (e.g. gravel resources and historic sites).
Moratoriums
Several Minnesota communities have recently enacted moratoriums to halt all or some types of development (e.g. large animal feed lots or residential subdivisions) until local officials can make critical improvements to their development decision-making process. By state law, a moratorium may be for up to one year and extended for up to another 18 months.
Using a Moratorium to Gain Natural Resource Information
A community may use moratorium as a time-out in which to conduct a natural resource inventory or investigate in more detail critical natural resources or issues (e.g. impacts of septic systems on lake water quality. In either case, the moratorium should be carefully timed so that the critical field information can be gathered and analyzed, implications discussed, and any needed revisions to policies and regulations made before the moratorium expires.
