Crediting Conservation

Land conservation has long been recognized as an important aspect of Chesapeake watershed stewardship — and of maintaining water quality in the bay and its tributaries. The Chesapeake 2000 agreement and the Chesapeake Bay Watershed Agreement of 2014 both set goals for land protection.

Over 18 million people currently call the Bay watershed home. By 2050, that population will likely increase to 22.5 million.  If recent trends continue, most new jobs and homes are expected to be located at the periphery of major cities (e.g., Harrisburg, Baltimore, Washington D.C., Richmond, and Norfolk) and major transportation corridors (e.g., I-81, I-95, I-66). These trends could change due to emerging technologies (e.g., driverless cars), more flexible workplaces and schedules, changing cultural preferences, the construction of new roads, state and local land use policies, land conservation efforts, and other factors.

In 2010, Chesapeake Bay TMDL (Total Maximum Daily Load) became the primary driver for managing water quality and nutrient and sediment pollution reduction, established 2025 as the year to achieve full implementation of all Best Management Practices (BMPs), and required states to account
for potential growth in pollution through 2025. Soon thereafter, conservationists became increasingly concerned that the TMDL did not directly account for — or “credit” — permanent land protection as a positive contribution to preventing future pollution loads. In 2013, the Chesapeake Bay Commission explored this issue in the report Crediting Conservation: Accounting for the Water Quality Value of Conserved Lands Under the Chesapeake Bay TMDL.

In 2018, the Chesapeake Bay Program (CBP) Partners agreed to account for the potential growth in pollution by basing their restoration plans on plausible future conditions for the year 2025. Because population growth and associated changes in land use can increase population, the Chesapeake Bay Land Change Model (CBLCM) was developed to forecast future scenarios of urbanization throughout the watershed based on the best available local and regional-scale data and information. The Chesapeake Bay Program adopted a “Current Zoning” scenario as representing the most probably land use conditions in 2025: this will serve as the TMDL baseline scenario for evaluting the effects of BMPs.

The CBP partners have crafted a set of thematic “what if” scenarios that include conservation and/or land use planning elements.  Each of these thematic scenarios assumes a variety of organizations and government agencies proactively pursue efforts focused on one of three themes: conserving forests and wetlands, conserving farmlands, or managing growth.  These thematic scenarios — referred to as the “Conservation Plus Family of Scenarios” — serve as strawmen for “land policy BMPs”, and as such they can be used to demonstrate the potential for crediting land use planning and land conservation efforts under the Bay TMDL restoration framework.

Each state will consider including land conservation and land use planning elements as BMPs in their Watershed Implementation Plans for the TMDL. The Chesapeake Conservation Partnership has worked with the CBP to ensure that the best available conservation data are available for use in WIP development.

Over time, adoption of land conservation and land use planning BMPs is expected to provide an important incentive for conservation — and a new tool for localities to meet the TMDL requirements.

For more information, see: Crediting Conservation FAQs