NPDES: Stormwater Best Management Practice, Conservation

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Stormwater Best Management Practice

Conservation Easements

Minimum Measure: Post Construction Stormwater Management in New Development and

Redevelopment

Subcategory: Innovative Practices for Site Plans

Description

Conservation easements are voluntary agreements that

allow individuals or groups to limit the type or amount of

development on their property to achieve certain

conservation purposes. A conservation easement can

cover all or just part of a property and can be either

permanent or temporary. Easements typically focus on

specific land uses, such as agriculture, forest, historic

properties and open space.

Easements can relieve property owners of the burden of

managing these areas. They shift responsibility to a

private organization (land trust) or government agency

that may be in a better position to take responsibility for

management and compliance issues associated with the

property. In some cases, property owners might realize

tax benefits by placing conservation easements on some

or all of their property.

Conservation easements may indirectly help protect

water quality. Land that property owners set aside in a

permanent conservation easement has a prescribed set

of uses or activities that generally restrict future

development. Often, this limits impervious surface

development and preserves an area’s natural hydrology.

Owners can evaluate the location of their land held in a

conservation easement to determine its relative ability to

provide water quality benefits. Property along stream

corridors and shorelines can act as a vegetated buffer

that filters out pollutants from stormwater discharge. The

ability of a conservation easement to function as a

stream buffer depends on the width of the easement and

type and condition of the vegetation within the easement

(see the “Riparian Forested Buffer” fact sheet).

Applicability

Conservation easements typically aim to preserve

agricultural lands and natural areas that development

threatens. For rapidly urbanizing areas, conservation

easements may provide a way to preserve open space

before land prices make it impractical for government

Conservation easements allow property owners to

conserve natural areas that may otherwise be developed.

agencies with limited budgets to buy land with important

cultural and natural features. Urban areas typically have

fewer conservation easements than other areas due to

the lack of available open space for purchase and the

high cost of undeveloped land. In addition, private land

trusts may limit the size and type of land that they are

willing to manage as conservation easements.

Implementation

Conservation easements ensure that land remains in its

current state long after the original owners no longer

control it. By agreeing to restrict the development rights

for a parcel of land, landowners guarantee that it will

remain in a prescribed state for a fixed period of time

(e.g., 30 years, permanent) while receiving tax benefits.

Often, state agencies and private land trusts have

specific qualifications for a property before they enter

into an easement agreement with landowners. Table 1

contains examples of criteria that private land trusts use

to determine if a property is worth managing in a

conservation easement.

https://www.epa.gov/npdes

EPA-832-F-21-031M

December 2021

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NPDES: Stormwater Best Management Practice—Conservation Easements

Table 1. Typical criteria that land trusts use

to determine feasibility of entering into

conservation easement agreements.

Criteria Details

Natural resource

value

Does the property provide a

critical habitat or important

environmental aspects worth

preserving?

Uniqueness of the

property

Does the property have unique

traits worth preserving?

Size of land

Is the land large enough to have

a natural resource or

conservation value?

Financial

considerations

Are funds available to meet all

financial obligations?

Perpetuity

Is the conservation agreement a

perpetual one?

Land trust’s

mission

Does the property align with the

land trust’s mission and the

organization’s specific criteria?

Conservation easements are applicable in all parts of the

country; many private groups, both national and local,

exist to preserve natural lands and manage conservation

easements. States also use conservation easements

and land purchase programs to protect significant

environmental features and open space. The U.S. Land

and Water Conservation Fund, a federally funded

program, provides 50/50 matching grants to state and

local governments to acquire land for public outdoor

recreational use.

Maryland has received national recognition for its

programs that provide funding for state and local parks

and conservation areas. The state is one of the first to

use real estate transfer taxes to pay for land

conservation programs. Funding for several programs

comes from this tax of one-half of one percent ($5 per

thousand) of the purchase price of a home or land, or

other state funding programs (MDNR, 2019). To date,

Maryland has preserved more than 1.75 million acres of

land, tracked through its interactive Protected Lands

Dashboard. Maryland’s conservation programs include:

 Program Open Space. This program, which has both

a s

tate and a local version, has acquired near

400,

000 acres of open space for state parks, loc

par

ks and natural resource areas. Every five years

tate, federal and local organizations develop

Land P

reservation and Recreation Plan that out

lines

acquisition and development goals in order to

aintain eligibility to receive Land and Wat

Cons

ervation Fund grants and guide the long ter

ision of Program Open Space

 Maryland Environmental Trust. This state-funded

agency helps local citizen groups form and operate

loc

al land trusts. It offers the land trusts technic

sistance, training, grants for land protect

ion

ojects and administrative expenses,

and

par

ticipation in the Maryland Land Trust Alliance

 Rural Legacy Program. This smart growth initiative

edirects existing state funds into a focused

dedic

ated land preservation program that specific

ally

aim

s to limit the adverse effects of spr

awl on

agr

icultural lands and natural resources. T

ogram purchases conservation easements f

large contiguous tracts of agricultural, forest and

nat

ural areas subject to development pressure,

and

it pur

chases fee interests in open space wher

public

access and use are necessary

ther examples where communities have strategically

used conservation easements for water quality purposes

can be found on EPA’s Green Infrastructure Web site.

The holder of a conservation easement—whether a

government agency or a private land trust—has certain

management responsibilities. Some examples:

 Ensure that the easement’s language is clear and

enf

orc

eable.

 Develop maps, descriptions and baseline

doc

umentation of the property’s characteristics

 Regularly monitor the use of the land.

 Provide information on the easement to new or

ospective property owners

 Establish a review and approval process for land

tivities that the easement stipulates

 Enforce the easement’s restrictions through the legal

syst

em, if necessa

ry.

 Keep property/easement-related records.

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NPDES: Stormwater Best Management Practice—Conservation Easements

Limitations

Conservation easements have limits as a stormwater

management tool. For example, there are significant

impediments to using these measures in heavily

urbanized areas, where the size, quality and cost of land

limits the viability and feasibility of such easements.

Depending on the specific type of easement, another

limiting factor can be its duration—if the easement does

not hold the land in perpetuity, long term water quality

protection may not be possible. In addition, easements

may not be able to address concentrated stormwater

impacts from developed areas, because property owners

use them more frequently outside of developed areas.

Maintenance Considerations

The responsibility for maintenance of property held in a

conservation easement depends on the terms of the

individual agreement. While many organizations assume

the responsibility for managing the easement property

and for meeting the terms of the easement, some land

trusts leave maintenance responsibilities to the

landowner.

Effectiveness

A conservation area’s effectiveness in protecting water

quality depends on how much land the property owner

conserves, conservation techniques, the land’s location

in relation to a waterbody, and the specific nature of the

easement. Generally, maximum effectiveness occurs

when those responsible for the site keep it relatively

undisturbed and ensure the retention of a site’s natural

hydrology. Any alteration of natural conditions, such as

partial development or limited agricultural use by

landowners, may reduce water quality benefits. The

downstream effects of these management actions—

whether positive or negative—tend to be enhanced the

closer the easement property is to the downstream

waterbody.

These benefits are difficult to measure directly, as the

purpose of conservation easements is to prevent

environmental impacts, not to remediate existing

impacts. Still, studies have explored the benefit of

conserving natural lands (or the impact of developing

natural lands), showing direct links between the level of

development and the health of benthic organisms in

local streams, which is an indicator of water quality (May

and Horner, 2002; Schueler et al., 2009; Walsh, 2004).

Over time, these observations have caused stormwater

practitioners to revise the broad goals of stormwater

management, adding a focus on restoration or

conservation of natural hydrologic processes to the

traditional focus on flood control and pollution mitigation

(Clark et al., 2010; Walsh et al., 2016).

Cost Considerations

The costs associated with conservation easements

include administrative costs and land management

costs. Generally, tax or fee programs fund these costs,

though specific arrangements depend on local

circumstances. For example, Virginia Beach’s Open

Space Special Revenue Fund receives partial funding

through a $0.44 dedication of restaurant meal taxes (City

of Virginia Beach, 2018), while organizations like

Alachua Conservation Trust rely on donations and

various grants to support the conservation of more than

53,000 acres of Florida land.

Additional Resources

Additional resources detailing design, implementation

and funding of conservation easement programs include:

 The Land Trust Alliance—a national leader in policy,

tandards, education and tr

aining.

 The Conservation Easement Handbook—a resource

or land conservation professionals dev

eloping

onservation easement programs, by the Land Trus

lliance and the Trust for Public

Land.

 Better Site Design: A Handbook for Changing

Dev

elopment Rules in Your Community (Part 1)—

handbook

by the Center for Watershed Protect

ion.

 The Pennsylvania Land Trust Association’s

Cons

ervation Tools Web page—a resource f

odel easements, tax rules and helpful articles fr

onservation professionals

 Managing Growth and Development in Virginia: A

Review of the Tools Available to Localities—a report

the Virginia Chapter of the American P

lanning

ssociat

ion.

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NPDES: Stormwater Best Management Practice—Conservation Easements

Additional Information

Additional information on related practices and the Phase II MS4 program can be found at

EPA’s National Menu of Best Management Practices (BMPs) for Stormwater website

References

City of Virginia Beach. (2018). Adopted operating budget: Resource management plan FY 2017–2018.

Clark, S. E., Baker, K. H., Treese, D. P., Mikula, J. B., Siu, C. Y., & Burkardt, C. S. (2010). Sustainable stormwater

management: Infiltration vs. surface treatment strategies. Water Environment Research Foundation.

Maryland Department of Natural Resources (MDNR). (2019). Land acquisition and planning. Maryland Department of

Natural Resources.

May, C. W., & Horner, R. R. (2002). The limitations of mitigation-based stormwater management in the Pacific Northwest

and the potential of a conservation strategy based on low-impact development principles. In Global solutions for urban

drainage (pp. 1–16).

Schueler, T. R., Fraley-McNeal, L., & Cappiella, K. (2009). Is impervious cover still important? Review of recent research.

Journal of Hydrologic Engineering, 14(4), 309–315.

Walsh, C. J. (2004). Protection of in-stream biota from urban impacts: Minimise catchment imperviousness or improve

drainage design? Marine and Freshwater Research, 55(3), 317–326.

Walsh, C. J., Booth, D. B., Burns, M. J., Fletcher, T. D., Hale, R. L., Hoang, L. N., Livingston, G., et al. (2016). Principles

for urban stormwater management to protect stream ecosystems. Freshwater Science, 35(1), 398–411.

Disclaimer

This fact sheet is intended to be used for informational purposes only. These examples and references are not intended to be

comprehensive and do not preclude the use of other technically sound practices. State or local requirements may apply.

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