Isthmus District Recommendations
see also: Isthmus District - Isthmus District Findings
Summary of Findings
The Isthmus district, by nature of its dense urban development, fails to meet the performance standards for several ecological attributes, but excels beyond performance standards for other ecological attributes characteristic of dense urban areas. The Isthmus is deficient in green space attributes, such as open space and natural areas, both in terms of performance standards and in comparison to other districts within Madison. However, the Isthmus not only surpasses every other district in Madison in terms of pedestrian and transit orientation, but notably excels beyond performance standards in these areas as well. As a result of its various ecological strengths and weaknesses, the Isthmus sets the standard for the rest of Madison in terms of transit and pedestrian connectivity, but will need to find innovative ways of creating adequate green space.
In terms of overall green space, the Isthmus is deficient in both public open space, based on the performance standards of 10 acres of open space per 1,000 residents, and community gardens plots, based on the standard of one community garden per 2,000 residents. The district has a total of 268 acres of open space, 99% of which is public open space. Yet with only 5.9 acres of open space per 1,000 residents, the Isthmus has a total open space deficit of 186 acres. As the district with the highest population density, the Isthmus lacks more open space than any area within the city. There are a few parcels within the district that are privately owned and recommended for public acquisition, but it not likely that the bulk of the 186 acres of open space will be acquired within the district itself.
The Isthmus district is served by three community gardens. The Atwood and East Main community gardens are located along former rail lines, and are among Madison's best examples of creative reuse of land resources. At 1/10 of an acre, the Reynolds garden is the smallest in the City, but also serves residents the City's most densely populated area, where space is at a premium. The Isthmus currently provides only one community garden space for every 15,000 residents, leaving the Isthmus a deficit of 19 gardens. With open space as scarce as it is in the district, the city will need to be open to alternative ways accessing gardening space for Isthmus residents in order to develop the 19 community garden sites needed to meet the desired standards.
The Isthmus has 22 acres of natural areas and forest fragments found within 6 patches, the majority of which lie along the Yahara River, in addition to Olbrich Gardens and Park and Orton Park. Because the Isthmus is densely populated, this amounts to less than ½-acre of natural areas for every 1,000 residents. The Isthmus has the least amount of natural areas in the City by far, and with the full and dense development characteristic of the district, new sizable natural areas will not be developed, and existing natural areas have very little room for expansion.
Street trees are one way the Isthmus can improve both its stormwater management and reduce the urban heat island effect, but it lacks 15% of the tree cover necessary to achieve the goal of 100% street tree coverage. Compared to other districts in the city, the Isthmus is average in this respect. The majority of streets lacking adequate tree coverage are in one of two areas. The central business district, with dense developments of commercial, office, and residential spaces is often built out to the lot line, leaving little to no room for tree plantings. While some downtown streets may be planted, others may require easements in order to permit planting along the public right-of-way. The other area in the district most seriously lacking tree coverage is the commercial district east of the Yahara River, where many arterials, including, Washington, Winnebago, Commercial, and Fordem, are lacking proper tree coverage. Siting tree lawns along these areas and planting trees on the edges of large street-fronting parking lots will help to remedy this problem.
As the Isthmus is the most densely populated district in the city, it is not surprising that it has the highest percentage of impervious cover, with a combined residential and non-residential impervious coverage comprising 1,369 acres, or 52% of the district's area. This is more than double every other district's total impervious coverage, except the Near West side. Yet, based on performance standards for impervious coverage in relation to population density, the Isthmus fares very well, only 2%, or 56 acres, above the prescribed limits. Further, on a per capita basis, the Isthmus actually has the fewest impervious parcels, with just 30 parcels per 1,000 residents, less than half the per capita amount for any other district, save the Near West side. With some long-term changes in roofing and paving practices, the Isthmus can recover the 56 acres by which it exceeds impervious coverage standards.
The Isthmus is exceptionally successful in transit and pedestrian friendliness. The performance standard for transit are based on the number of minimum density census blocks within ¼ mile of a transit stop, and in Madison, the Isthmus is the only district to achieve 100% transit coverage. That is, every census block within the Isthmus district is located within ¼ mile of a bus stop, providing district residents and employees with excellent transit usage opportunities. In terms of pedestrian orientation, standards are derived from the percentage of residential sidewalks, with the standard being 95% coverage. Within the Isthmus district, 99% of the residential parcels have sidewalks, while in the rest of Madison the percentiles are considerably lower. Pedestrian and cyclist conductivity is further enhanced by the dense street grid, short blocks, and the number of bike paths and street bike lanes found throughout the Isthmus.
Recommendations by Goal
Though the Isthmus must implement several changes to meet our performance standards, we believe it is possible for the district, and the rest of Madison, to become a model of ecological sustainability. Already well endowed with transit service, street trees, and pedestrian connectivity, the Isthmus serves as a model district for reducing per capita energy consumption and greenhouse gas emissions. As noted above, the primary challenge for the district entails the provision of sufficient green space for residents. We believe that the development of rooftop gardens - the creation of a green patches above the City - will provide an important ecological amenity as the density of the district continues to increase in future years.