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Transferring development rights is principally a way to compensate sending site landowners for protecting their land from development and subsequently allow developers to achieve increased density in qualified receiving areas, but there are other potential benefits associated with TDRs - for both sellers at sending sites and for developers at receiving sites.

Sending TDRs from your property can reduce your property taxes.

When development rights are "certified" for transfer from a sending site, a conservation easement is placed over the sending site property. Because conservation easements limit some or all of the future development and preserve "conservation values" of a property, easements are one of the ways to achieve property tax reductions through King County's Public Benefit Rating System (PBRS). There are other requirements for enrollment in the PBRS program, but generally speaking, if a property is eligible for the TDR program it will also be eligible to enroll in the PBRS program, and vice versa.  Please visit the PBRS website to learn more about reducing your property taxes with TDR.

TDRs can satisfy Traffic Concurrency requirements

New developments or subdivisions in Rural areas (outside the Urban Growth Area) are required to meet "Traffic Concurrency" requirements. That is, for each new development or subdivision, there must be adequate transportation infrastructure within a given commuting area – called a “travelshed” –  to accommodate increased traffic that comes with additional development. Some travelsheds in King County are currently closed to subdivision development and are called “non-concurrent” because they lack the necessary road and transportation capacity.

However, in these non-concurrent travelsheds, since transferring development rights results in permanently removing development potential from sending sites (via conservation easements), which creates a net long-term reduction in traffic, TDRs can be used to satisfy traffic concurrency requirements. This applies as long as the TDR sending site is in the same travelshed as the proposed development or subdivision. If TDRs are used to meet traffic concurrency requirements, that is their only value, i.e. TDRs used for traffic concurrency cannot also be used to increase density.

Learn more about traffic concurrency requirements on King County Department of Transportation's website.

See a map of Traffic Concurrency Zones.

Rural TDRs may allow you to build a larger ADU

King County Code chapter 21A.08.30 outlines the rules for building an Accessory Dwelling Unit (ADU). In the Rural Area zones, ADUs are allowed under certain conditions. In most cases, these ADUs are limited to 1000 square feet. However, in certain cases a Rural TDR can be used to increase the allowed size of ADUs to 1500 square feet. It is important to note that each parcel and development proposal will have a unique set of conditions and circumstances; final authority rests with DPER to permit residential ADU's. Contact DPER or a TDR program staff member if you have questions about using TDRs to permit a larger ADU.

TDRs Can Help Satisfy Greenhouse Gas Emissions Requirements

The newly adopted 2008 King County Comprehensive Plan stipulates that TDRs are an option available to developers to mitigate for project-related greenhouse gas (GHG) emissions that exceed a set threshold. That is, developers who use TDRs for increased density can also capture the GHG reducing benefits that TDRs create to meet emission reduction requirements. The requirements, which are forthcoming in 2009, will be in accordance with the State Environmental Policy Act.

The idea is that TDRs carry with them a GHG reduction "value" which is based on the vehicle miles that will not be traveled as a result of restricting future development on rural TDR sending sites and relocating the development potential onto projects within existing urban areas – areas known to require less driving and commuting. In August 2011, the Sightline Institute published a report analyzing how TDRs reduce climate-warming emissions which explains the method for determining reductions and estimates emissions reductions related to certain types of TDR transactions.

For questions about alternative uses of TDRs contact Michael Murphy at 206-477-4781 or Charlie Governali 206-477-8767.