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King County operates the King County TDR Bank, which has three key roles:

(1) Facilitate the private TDR market by bridging the time gap between willing sellers and buyers of TDRs;

(2) Act as a revolving fund for continued land protection through buying, holding, and selling TDRs (proceeds from TDR sales are used for future land protection); and

(3) Catalyze city-county TDR agreements by strategically acquiring development rights from high priority conservation rural / resource lands in the County that are of compelling interest for specific cities to see protected.

The TDR Bank was established in 1999 with an appropriation by the Metropolitan King County Council of $1.5 million to purchase TDRs and continues to play an important role in the King TDR Program. The primary function of the Bank is to facilitate the market in transferable development rights by engaging in high conservation priority transactions to open new markets for private TDR participants in cities that partner with King County. The remainder of this page covers several topics related to the King County TDR Bank:

Options to buy TDRs

In addition to direct TDR sales, the Bank is offering potential buyers options to buy TDRs. This way developers can, with a minimal outlay of capital, lock in a certain number of TDRs at a certain price for a specified length of time. This is especially valuable for development projects inside cities following passage of the new Tax increment Financing / TDR bill passed by the State Legislature and signed into law by the Governor in 2011 (SB 5253). In addition the King County TDR Bank can develop creative extended purchase and sale agreements with prospective buyers to ensure reduced developer risk and minimize up-front outlays of capital for TDR purchases.

Please contact Michael Murphy. for more information about options to buy TDRs from the Bank and SB 5253.

Revenue-share with cities

 To open new markets for TDRs inside cities, the Bank can, depending on the city-county arrangement, enter into a revenue share agreement with the city. Under such an agreement the county provides the city with a portion of the proceeds it receives from sale of TDRs used for increased density inside the city. The funds provided to the city can be used for infrastructure improvements, creation of parks/open space, and streetscapes etc. inside the city.

In this way Bank dollars are used as amenity funds to help facilitate development right sales by assisting cities with infrastructure improvements needed to accommodate the extra density. Before amenity funds may be spent in a city, an interlocal agreement must be in place between the city and the county.

Development rights purchased from the TDR bank can only be used on receiving sites in urban unincorporated King County or incorporated cities. An interlocal agreement must be in place between King County and a city before TDR Bank development rights may be transferred to a development project within the city. As of August 2011, King County has interlocal agreements in place with the following cities: Bellevue, Issaquah, and Sammamish.

TDRs from sending sites must also meet any additional criteria specified in the particular interlocal agreement before the rights may be applied to a development project. For example, a particular interlocal agreement may specify that the city will only accept development rights from a specific area of rural King County that was of compelling interest to the City to see protected. Therefore, not all of the TDRs in the bank would be suitable for a project in a particular city.

For questions about the TDR Program please contact Michael Murphy, TDR Program Manager, or Charlie Governali, TDR Project Manager, King County WLRD Rural and Regional Services Section.