What locations in the Twin Cities are eligible for LEED ND: Part 2

After HUD announced that they would begin scoring grant projects on “location efficiency” using LEED ND as a guide, I got curious as to what that might mean for the Twin Cities region. In Part 1 of the series, I began looking at what requirements LEED ND has for “location efficiency” and came up with a map that identifies areas of the region that are basically off-limits due to special environmental or land use characteristics. This was based on prerequisites 2 – 5 in the Smart Location and Linkage topic area of LEED ND. This post will focus on the last prerequisite in Smart Location and Linkage: Smart Location.

This exercise isn’t supposed to be just about HUD, but about what planning in our region might look like if location efficiency, smart growth and infill development were prioritized over greenfield development.

Instead of being about what is off-limits, as the other prerequisites in SLL are, Smart Location is about identifying locations that are best for development. The “intent” of the Smart Location prerequisite is described in the LEED ND rating system as:

To encourage development within and near existing communities and public transit infrastructure. To encourage improvement and redevelopment of existing cities, suburbs, and towns while limiting the expansion of the development footprint in the region to appropriate circumstances. To reduce vehicle trips and vehicle miles traveled (VMT). To reduce the incidence of obesity, heart disease, and hypertension by encouraging daily physical activity associated with walking and bicycling.

The requirements of Smart Location, in brief, are as follows:

  1. All projects must be within a legally-adopted, publicly-owned, planned water and wastewater service area AND
    1. the project must be on an infill site OR
    2. an adjacent site with connectivity OR
    3. a transit corridor with adequate service level OR
    4. a site with nearby neighborhood assets.

So, sewer and water are required for all projects, and then the project must meet one of the last four criteria.

Water and Wastewater Service

Sewer is relatively straightforward. In the Twin Cities metro area, we have a planned Metropolitan Urban Service Area, which is intended to identify phasing for development. While cities are supposed to identify development phases of 2010, 2020 and 2030, it is not unheard of for cities to amend the phasing based on the wishes of landowners and developers. If existing pipes are close enough, cities may extend them or ask developers to pay the cost of extension. The point is, the phasing is not an iron law. Therefore, identifying the 2030 MUSA boundary as the limit of the first requirement seemed reasonable. Also, the 2010 and 2020 MUSA boundaries are not significantly different to exclude much of the area that will be eligible anyway.

Infill Site

The rating system has a complex definition of infill site which basically is a way of measuring how much of the land surrounding the project boundary has been previously developed. There are a number of reasons why my estimates of what is infill may not be exactly accurate, including not knowing specifically how any particular project site would be shaped, but what I’ve come up with is a conservative estimate of areas that would qualify as infill in the metro. So this map of eligible infill sites probably represents a slight underestimation of the eligible areas, but better safe than sorry.

Adjacent Sites with Connectivity

Areas With High Intersection Density

This criterion allows projects to meet the prerequisite if they are adjacent to previously developed areas that have a street-network density of at least 90 intersections per square mile (measured along at least 25% of the project boundary, within 1/2 mile). There are also requirements about how frequent through-streets must be at the project boundary. Street network (or intersection) density is an important determination of walkability and transit use.

To measure intersection density, I broke the metro into a grid with each square being 1/2 mile on a side. I then counted the intersections in each grid square. This map shows the intersection density throughout the metro. For any 1/2 mile project boundary, I figure you’d need at least 23 intersections in the adjacent grid square to meet the criteria. Singling out those squares with at least 23 intersections and buffering them to capture adjacent land that would be eligible, you get this map.

Adding areas with high intersection density to the “eligible” category does not really expand the possibilities for LEED ND in the Twin Cities, since there are much greater infill opportunities than sites with high intersection density, and the infill sites largely overlap these areas.

Transit Corridors

Transit Corridor or Route with Adequate Transit Service

Projects can also qualify if they are within 1/4 mile walk distance of bus stops, or within 1/2 mile walk distance of BRT, LRT, heavy rail, or ferry terminals AND the service at those stops meet certain thresholds (e.g. 60 trips per weekday). Not all the bus stops in the metro met this threshold. Also, the Northstar Commuter Rail does not meet the threshold due to low numbers of trips. Again however, this path to eligibility does not add much land beyond what is already included as potential infill.

Sites with Nearby Neighborhood Assets

Finally, sites can also qualify by being located within a 1/4 walking distance of 5 diverse uses. Without parcel data, I was unable to do any analysis of these locations. However, like some of the other areas above, I don’t think this option would add much area outside of what is eligible from being infill. So while I technically may have missed something, I’m relatively confident that any site that qualifies under this category has already been taken care of by one of the above.

The Results

Location Efficient Sites

Identifying the final eligible areas is mostly an exercise in layering all the eligible areas together, then cutting out any ineligible areas (areas outside the MUSA and ineligible areas that were computed in the last post). I also excluded any areas that were under 1/2 acre, assuming that this would be the minimum size for an area to be considered realistically developable.

Here is the final map. Areas in green are the locations in the metro that could be considered “location efficient” according to LEED ND, and perhaps soon, HUD. In my opinion, a surprising amount of the metro area is eligible.

In the next post, I’ll try to do a little bit more analysis of this final result by city. I’ll also look at another critical factor, whether a LEED ND project would likely be allowed in a particular area given the existing intensity of development in that area (and the planned intensity). In other words, would a community’s planning and zoning rules allow a LEED ND project?

14 thoughts on “What locations in the Twin Cities are eligible for LEED ND: Part 2

  1. Excellent analysis, Brendon. Looking quickly through the maps, it seems that the eligible areas are just everything inside the MUSA minus the areas deemed ineligible for environmental sensitivity, etc, that you analyzed in Part 1. The other criteria do not seem to make much of a difference. Some of those “or”s should be replaced with “and”s.

    • True, Paul. The requirement for being “infill” permits a larger area than any of the other criteria, and much of the area currently inside the MUSA has already been developed, with a few exceptions. There is a prerequisite in a different category that requires a minimum density, so next time I hope to look at what areas would actually likely permit a LEED ND-type development.

  2. I think the NPD Prerequisite #3 Connected and Open Community will limit potential sites much more than the SLL prerequistes. NPD PR3 requires projects with internal streets to have at least 140 intersections/ sq mi and projects without internal streets to have at least 90 intersections/ sq mi within 1/4 mile of the project boundary.

    Based off of your map, only the dark blue areas will be eligible. Alleys count in the intersection density calculation so Minneapolis is still fair game, but most suburban areas after the first ring will drop off.

    Can’t wait to see the next set of maps!

    • Very true. I have avoided that one up until now, because it partially dealt with what was inside the project boundary. Also, to be honest, I kind of overlooked that option for projects without internal streets, although in LEED ND I’m not certain how common these would be. In the next post, I’m hoping to tackle NPD p3 and NPD p2.

    • I want to clarify that NPDp3 looks at the intersection density that is designed for the project if the project includes streets. This is something that the designer has some control over. This conversation seems to be considering LEED-ND more for existing neighborhoods. LEED-ND has been designed for new development or redevelopment within existing neighborhoods.

      If there are no streets inside the project, then that is when the area within a 1/4 mile radius is evaluated for existing intersections.

      • Yes, I understand that NPDp3 mostly deals with what is internal to the project, and thus is partially at the discretion of the project designer. However, it is somewhat unlikely that a development would have significantly higher intersection density than the area around it given local codes, politics and the attitude of the city engineer. Thus, I’m looking at it more as an information item, not a final determination of eligibility.

  3. If I ran HUD, I surely would ratchet down the eligibility, much like Paul suggests. Bottom line: you can’t live in Elko New Market and consider yourself location efficient, at least not in a LEED-certified way.

    • Thanks Eliot, it looks like you guys really have this process down. One of my limitations, described in previous comments, is that I don’t have access to the parcel dataset for the region, so I have to use other geospatial land use data, which may not be quite as accurate.

      In the Twin Cities we have a regional planning agency responsible for determining what levels of growth each community must plan for. So I am attempting to look regionally, to explore whether these concepts could help provide a guide for a more sustainable region. As I’m sure you know, one community limiting growth or trying to increase density may only mean that development moves to the next adjacent community with fewer protections or restrictions.

  4. Pingback: What locations in the Twin Cities are eligible for LEED ND: Part 3 | Net Density

  5. Pingback: Joe Urban » Blog Archive » The Hot White Line of LEED-ND

  6. Pingback: [Personal Project] LEED-ND Smart Location andLinkage | Adventures in V515

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