A New Chapter for a Seaside City
The City of Duluth, Minn., began an entirely new chapter in November 2010 ... a Unified Development Chapter, that is, of the Duluth Legislative Code. Sound exciting? Probably not, but if you're interested in water quality, you may want to push back that creeping feeling of boredom at the mention of a "legislative code" and keep reading.
Water is one thing that makes Duluth exceptional. The city of 87,000 overlooks Lake Superior, North America's largest inland sea. It also spans 14 trout streams and is bounded by the St. Louis River, a major tributary to Lake Superior. Duluth's Unified Development Chapter recognizes this water and its ties to the land around it.
The impetus for this new chapter began over a decade ago when the city started to develop a new comprehensive plan to set a vision for the future of Duluth. In 2006, with a fresh vision in place, the city reexamined the laws, regulations, and policies on the books. Considering that the previous regulations dated to 1958, it became clear that new rules were needed. It's important that such regulations are written carefully. Enforceable by law, they determine what property owners can do on their land and plot a course for the community. They affect residents and visitors in tangible ways including aesthetics, safety, recreation, transportation, and, yes, impacts to natural resources.
Most people, if asked about water-related land use regulations, would perhaps mention lot size or setbacks from shorelines. Others might talk about wetland protection or erosion control practices. These important regulations have been updated in Duluth's new code. But four lesser-known facets of the code are worth applauding as contributions to a future that includes outstanding water quality. These examples highlight innovative ways that Duluth is purposefully moving towards its future.
Parking Lot Landscaping Requirements
Typically dark and impervious, parking lots can produce huge volumes of warmer-than-average runoff carrying salt, sand, dirt, oil, and other pollutants. Few would argue that parking lots are aesthetically pleasing. With a few requirements in the new code, Duluth's next iteration of parking lots will include 10-15 percent of the space as landscaped areas, with trees planted so that at maturity they will shade at least 30 percent of the pavement. Leaves from these trees will intercept rainfall and keep the runoff (and cars) cooler in the summer. These landscaped areas are required to be set lower than the pavement, meaning the runoff will have a chance to filter into the ground and cool off before reaching nearby streams or Lake Superior. Research has found that parking lots shaded by trees can last longer, so Duluth's parking lot regulations may help save money, too.
Prior to the new code, a minimum amount of parking was set for new developments in Duluth. Under the new code, minimums are still set, but so are maximums. The number of spaces allowed is reduced 20 – 30 percent if the business or development is within a half- or quarter-mile (respectively) of a bus route. In some cases, adjacent businesses can share spaces, saving money on both construction and maintenance. With an estimated 800,000,000 parking spaces in the U.S. (about 3 for every car), parking spaces are an expansive issue.
According to the new code, new subdivisions in the more rural parts of Duluth will incorporate conservation design principles to preserve undeveloped land. Duluth's new regulations for these rural subdivisions set maximum lot sizes, with the result that 50 – 85 percent of the land is left undeveloped, which means significantly less runoff and more open spaces for residents to enjoy. Though it may sound counterintuitive, larger lots can create a greater impact on water quality than smaller lots. If four houses are placed on one acre, there will be more runoff than if just one house was put there, but those other three households worth of people still need somewhere to live. A recent study in Duluth found that using conservation design principles can reduce runoff by up to 106 percent compared to traditional large-lot development.
For new subdivisions, many communities require developers to submit a detailed technical plan, with the exact locations of lots, streets, and utilities, before the community reviews the proposal. By this time and before getting any feedback from the community, the developer has invested significant money in those plans, which can require soil analyses, stormwater studies, and consultations with engineers. Naturally, developers are recalcitrant to spend more money to make big changes. Duluth's new code requires, instead, a preliminary concept plan, where the general layout of lots, streets, and natural areas are indicated. This delays the expense of a technical plan until after discussions with city staff. At this point recommendations to better protect resources or otherwise help the project meet the community's goals can be made without the developers incurring additional expense.
Jesse Schomberg is the Program Leader and Coastal Communities and Land Use Planning Extension Educator for Minnesota Sea Grant. He worked with officials, staff, and residents as Duluth's new chapter was being written; he also provided 27 pages of comments and suggestions on the draft ordinance.
By Jesse Schomberg