• TDRs have sufficient value to buyers and sellers to sustain an active market to accomplish preservation goals,
• The county has strong Comprehensive Plan and Zoning policies that support use of TDRs,
• Administration of TDRs is simple, efficient and predictable, and
• The TDR program has broad public support.

• TDRs make economic sense to developers in a robust real estate market for new housing development, where the demand for additional dwelling units greatly exceeds the base-level zoning density in designated receiver areas.
• Forward thinking elected officials considered the broad public interest in land preservation and were willing to make unpopular decisions that impacted a large number of people. They adopted TDR programs to gain political support for and mitigate anticipated negative impacts of downzoning, but this was only one part of a larger implementation strategy for managing growth and land preservation.
• Counties calibrate zoning rules for sending and receiver areas in support of the TDR program. In Montgomery County TDRs were established in connection with significant downzoning of farmland to preserve the agricultural land base of the community, and in Calvert County downzoning was implemented after TDRs were adopted to limit growth and maintain the demand for TDRs.
• Several large receiver areas were designated, with bonus density ratios for using TDRs that exceed the base level as-of-right density by more than 100% and as high as 700% in Montgomery and 1900% in Calvert.
• The demand for TDRs was carefully balanced with the total available supply of TDRs during the administration of the program, with public intervention in the market when necessary to sustain the price of TDRs through occasional purchases of TDRs by the county.
• County government requires TDRs for any increase in zoning density in receiver areas.
• TDRs were offered as one tool in a menu of land preservation alternatives to landowners, including active and well-funded Purchase of Development Rights (PDR) programs.
• TDR sending sites are protected by easements on land from which TDRs have been sold, permanently restricting the land to agricultural or forestry uses.
• Sustained professional staff support for implementation of the TDR program was provided to explain the program to the landowners and the public, monitor the progress of the program, and recommend changes to make it more effective, such as rezoning to increase demand for TDRs in receiver areas.
• The TDR program and the zoning supporting it were changed over time to maintain a demand for TDRs and to control development in rural areas. The original program was not complete when it was first enacted, but was modified as experience was gained.

• A TDR voluntary program was established as an option for private landowners to protect their equity and enable them to sell development rights, while the county maintained permissive rural zoning also allowing these landowners to utilize the development rights on the sending sites.

• TDRs were initially established at a time when comprehensive plans or other proposals recommended downzoning to preserve farmland (e.g. 1 du/20 acres or more), but elected officials decided not to downzone, or to couple limited downzoning with incentives allowing cluster development at higher densities within the agricultural sending areas.
• Weak real estate markets for new development in either the sending or receiving areas or both, where the base-level zoning density in the receiver area is rarely exceeded by what developers can build by right.
• Community opposition to higher density residential development in receiver areas, in some cases even to densities allowed by the base level zoning without TDRs.
• Prices for TDR sales that are lower than the per acre sale value of easements to MALPF or other local or state PDR programs, and substantially lower than the sale value of development lots permitted by local zoning in TDR sending areas.
• The availability of other alternatives for developers to obtain density bonuses to achieve the desired market for new development, including upzoning, variances, cluster zoning, non-contiguous development, planned-unit development, or project design features or amenities committed to in Developers Rights and Responsibility Agreements.
• Administrative constraints to the free-market sale of TDRs, causing uncertainty and delays in their sale. These include government approvals of the use of TDRs on the receiver sites which include discretionary public hearings for new development that can limit the use of TDRs for higher density; simultaneous joint approvals of sending and receiving site transfers delaying the sale of TDRs until they are approved for use in the receiving project: or required documentation of the development potential of the sending sites to qualify for eligible TDRs (e.g. net-area TDRs).

Adoption of State TDR Legislation similar to the New Jersey State Transfer of Development Rights Act, providing state review, guidance and technical assistance for the establishment of county TDR programs. The State could also establish a framework and guidelines for coordination and cooperation in the annexation process established by the General Assembly in 2006 by H.B. 1141, where TDRs would be part of the discussions.

Success with TDRs is more likely in counties that have zoned rural lands to protect agricultural and natural resource lands, limiting allowable residential densities to 1 dwelling per 20 acres or more, as several counties in Maryland have done.

Source: The Feasibility of Successful TDR Programs for Maryland’s Eastern Shore, Eastern Shore Land Conservancy, Inc. January 2007.