The City of Cambridge, 6.5 square miles is size, is separated from Boston by the Charles River. It has a population of 101,355 (2000) and a college population of over 32,000, primarily at Harvard, Radcliffe and the Massachusetts Institute of Technology.
Cambridge uses TDR to encourage the concentration of development near public transportation.
In 2001, the City adopted Citywide Growth Management policies and zoning recommendations designed to reduce traffic and other growth-related impacts. The Citywide effort was followed by rezonings that employ TDR to achieve land use goals in three neighborhoods: Eastern Cambridge, Cambridgeport and Concord-Alewife.
In Eastern Cambridge, TDR provisions encourage the reduction of density close to existing neighborhoods and facilitate development near transit services. The TDR Donating District and Receiving District are described in the Code. Gross floor area (GFA) can be transferred from any lot in the Donating District to any lot in the Receiving District subject to approval of a special permit from the Planning Board.
When the owners of non-residential floor area choose to use the TDR option, they must permanently restrict all non-residential development from the site. Following a transfer, the Donating Lot must be used for a park or for residential purposes at a floor area ratio (FAR) of at least 0.75. The GFA available for transfer is either the potential non-residential floor area as allowed by code or the actual floor area from an existing building proposed for demolition, whichever is greater. Residential development can also be transferred as long as FAR 0.75 of residential remains or is built on the donating site.
The transferred GFA is subject to dimensional limits in the Receiving District but is exempt from FAR or GFA limitations. Transferred non-residential GFA may be applied to any use allowed at the Receiving Lot but transferred residential GFA can only be used to create bonus residential GFA at the Receiving Lot. In considering approval of the special permit, the Planning Board must be assured that the proposed development is consistent with the Eastern Cambridge Plan and Design Guidelines and that the proposed Donating Lot changes will occur, such as the demolition of existing structures, the construction of new residential buildings or the creating of a park.
The Cambridgeport ordinance calls for the transfer of 103,250 GFA from a specified Donating Lot to a specified Receiving Lot. The transfer would allow for the creation of a 59,000 square foot park at the Donating Lot. After the specified Donating Lot becomes a park, the code allows other parcels to be considered as Donating Lots. The transfer would be subject to approval of a Special Permit to ensure that the proposed park and receiving site development are consistent with all design regulations.
In 2002, a Study Committee was formed to address the Concord-Alewife area in western Cambridge. As a result of that effort, the Concord-Alewife Rezoning and Design Guidelines were adopted on June 26, 2006. These changes have been incorporated into the Cambridge Zoning Ordinance and Zoning Map. The new zoning generally lowered densities for as-of –right development and allows prior levels in six overlay districts only via special permit. In addition, a TDR component encourages the redirection of development from west to east, moving growth closer to public transit.
The TDR provisions, like those in Eastern Cambridge, allow Donating Lot landowners to transfer the maximum FAR permitted by zoning or the actual GFA of an existing structure, whichever is greater. Donating Lot owners have the option of retaining some development potential on site either in new construction or existing buildings. Alternatively, all GFA may be removed to allow for the creation of a park. Transferred non-residential GFA can be used for any use allowed at the Receiving Lot but transferred residential GFA must be used for bonus residential development. Transferred GFA is not subject to GFA or FAR limitations but must meet other dimensional requirements.