The Town of Troy, population 2,328 (2000), lies in St. Croix County in western Wisconsin, across the St. Croix River from Minnesota. Interstate Highway 94 crosses the river at the City of Hudson, one mile north of Troy and 19 miles east of downtown St. Paul. Given its location within the greater Twin Cities Region, Troy has been concerned about agricultural land preservation. According to an article by Rhonda Ambuehl in the Spring 2007 issue of the Land Use Tracker, the Town originally considered spearheading a countywide TDR program but abandoned that idea out of concern that Troy would become the receiving area. Troy also considered a purchase of development rights, PDR, program but the citizens were reluctant to pay additional taxes to fund the program. Ultimately, the Town adopted a cluster development subdivision ordinance that later evolved into the TDR program described below.

Troy’s TDR program is designed to preserve the best farmable land. Troy uses exclusive agricultural zoning to protect the owners of farmland from nuisance claims and to qualify land for tax credits under Wisconsin’s Farmland Preservation Program. In addition, the Town adopted a requirement that land zoned exclusive agriculture must have an approved farm plan prior to any subdivision of land that would create lots of 35 acres or less. Landowners can choose between a 40/60 plan and a 50/50 plan. Under a 40/60 plan, the most agriculturally-productive 40 percent of the total parcel area is secured by a conservation easement that limits future subdivision to a density of no more than one unit per 12 acres (unless this 40-percent portion becomes the receiving area for an inter-farm TDR transfer as described below.) The remaining 60 percent of the parcel can be proposed for subdivision at a density of one dwelling per three acres, a minimum lot size of one acre and a buffer space of one undeveloped acre per lot. Under the 50/50 plan, half of the original farm site is secured by a conservation easement limiting subdivision to a maximum density of one unit per 12 acres and the other half can be subdivided to a maximum density of one unit per three acres with individual lots no smaller than 2.5 acres but no buffer space requirement.

With some exceptions, eligible TDR sending sites include farms zoned exclusive agriculture and subject to an approved farm plan as described above. Intra-farm transfers can occur as long as the receiving sites are part of the less-agriculturally –productive 60 percent or 50 percent of the farm plan boundary where subdivision to a density of three units per acre can be proposed. One TDR is generated at a sending site for each lot that could be created in accordance with the parcel’s farm plan.

The transfer ratio is one-to-one: one additional lot can be created at the receiving site for each TDR. When TDR is used, maximum density is limited to one unit per 1.5 acres, a doubling of the density allowed under the farm plan. Minimum lot size is one acre when the receiving site is served by individual wells and septic and 0.25 acres when served by municipal or equivalent private water and wastewater treatment facilities.

In addition to the intra-farm transfers described above, the Troy code allows “inter-farm” transfers from a sending area to “another area in the Town” provided that the receiving site is also subject to an approved farm plan. In an inter-farm transfer, the receiving area can be that portion of the farm planned for subdivision to smaller lots, as in the intra-farm transfers, as well as the portion of the farm under conservation easement limiting subdivision to larger lots. In the later case, TDR can be used to change allowable density from one unit per 12 acres to a maximum of one unit per six acres.

All proposed transfers require a TDR permit. In considering whether or not to approve the permit, the Town Board considers the following seven criteria.

1. The transfer must economically benefit both the sending and receiving site owners.
2. Sending areas are limited to land zoned exclusive agriculture as of 1999 or parcels of at least 35 acres containing a meaningful amount of productive farmland.
3. The proposed transfer must achieve the goals of the TDR program.
4. Receiving areas can only be located on prime farmland if the purposes of the TDR program are better served by the proposed transfer.
5. Areas zoned conservancy cannot receive TDRs.
6. TDRs cannot be transferred into previously created subdivision lots or outlots.
7. The receiving site subdivision must comply with all applicable development standards.

According to Ambuehl, the first transfer under Troy’s TDR ordinance occurred in 2003. In 2009, the Wisconsin chapter of the American Planning Association recognized Troy Town Supervisor Dan Pearson with its Distinguished Leadership – Citizen Award for his work in designing the TDR program as well as being the first farmer to use it.