Summary: Smart Growth: Twin Cities

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THE SMART GROWTH TWIN CITIES DEVELOPMENT SCENARIOS INDICATOR MODELING SUMMARY OVERVIEW

INFORMING THE BLUEPRINT

During the past two years, the Smart Growth Twin Cities (SGTC)

The Smart Growth Twin Cities process represents an important step

process has incorporated extensive input from public workshops,

in the development of Blueprint 2030. The Blueprint will chart a

local comprehensive plans, business associations and regional

course for future growth and development in the Twin Cities region.

transportation policy into the creation of three alternative development

The following seven objectives form the core of the Blueprint:

Scenarios for the Twin Cities Region. For the SGTC process, each

- Increase lifecycle and affordable housing

alternative future illustrates a distinct way in which the Twin Cities can

- Preserve and protect natural resources

accommodate the Region’s next 280,000 households (approximately

- Support rural communities and preserve agricultural lands

580,000 people) and 360,000 jobs.

- Provide greater transportation choices linked to development patterns and jobs

Ranging from auto-oriented to transit-oriented, the Scenarios vary in

- Reinvest in fully developed and older communities

land consumption, levels of reinvestment, walkable development,

- Invest in new, developing communities

density, and other development characteristics. The land use variations

- Focus growth and redevelopment in urban and rural centers along corridors

in each Scenario hold different consequences for regional housing diversity, transportation choice, air quality, public infrastructure costs,

By measuring the consequences of the SGTC development Scenarios,

agriculture and environmental preservation. Each Scenario has

the Metropolitan Council will be able to weigh particular advantages

undergone extensive land use and transportation modeling to measure

and disadvantages of each Scenario against these core objectives. The

these consequences and better understand the implications of various

Council can then incorporate particular elements or patterns into the

regional development patterns. These findings will serve as essential

Blueprint that align with the seven objectives, or choose to avoid

input as the Metropolitan Council develops Blueprint 2030.

patterns that are not consistent with local and regional goals.

Current Plans Scenario

Regional Workshop Scenario A

Regional Workshop Scenario B

The above figures provide a sense of land consumption in each development Scenario. The colored areas represent the newly developed land in each Scenario, also referred to as the increment. Gray represents existing developed land.

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THE SGTC DEVELOPMENT SCENARIOS

LAND CONSUMPTION

The Current Plans Scenario represents a mosaic of local comprehensive

A comparison of land consumption illustrates one of the most

plans in the region and is mainly auto-oriented. Considering the growth

dramatic differences between the development Scenarios. The Current

forecasts, local jurisdictions generally over-planned commercial land.

Plans Scenario consumes 286 square miles of land in the Region,

Likewise, local plans often did not provide enough multi-family

significantly greater than the 152 square miles developed in Regional

housing or plan for walkable development types. Thus, the Current

Workshop Scenario A and more than double the 136 square miles

Plans Scenario consists of low-density, often single-use development

developed in Regional Workshop Scenario B. Higher levels of

and little reinvestment.

reinvestment, often with higher-density development, reduced the

Regional Workshop Scenario A is derived directly from the local and

overall land consumption and development of existing agriculture

regional public workshops. Regional Workshop Scenario A balances

and undeveloped land in the Regional Workshop Scenarios.

more compact, auto-oriented development with a greater amount of

Reinvestment and density are further discussed in the following

development that is walkable, particularly along the planned 2025

sections.

Transit Network and on underutilized land in existing urban centers. It also provides more housing choices than the Current Plans Scenario.

LAND CONSUMPTION COMPARISON

Regional Workshop Scenario B is also based on public input from the workshops, but it concentrates compact, walkable centers along the Transit Network to a greater degree than Workshop Scenario A. Regional Workshop Scenario B incorporates the greatest amount of reinvestment and rural conservation development. It also provides the greatest diversity of housing. Both Regional Workshop Scenarios preserved known green corridors in the region.

ASSUMPTIONS All three Scenarios incorporate the same set of assumptions regarding environmentally constrained land. Growth was not allocated to 100year floodplains, National Wetlands Inventory wetlands and slopes greater than 18 percent. When the Metropolitan Council - Department Acres of Development

of Natural Resources (DNR) natural resources inventory and assessment is completed, the Council and the DNR can refine the

Land Consumption Agricultural Land Developed Prime Ag Soils Developed

definition of environmentally constrained lands. The same set of

Current Plans

Workshop A

Workshop B

182,922 95,205 56,885

96,972 45,884 34,419

87,173 41,342 31,953

tools was used to build each Scenario: a set of 16 development types, each with a unique number of dwelling units and jobs per acre and with a unique mix of housing and commercial land use types. These are the same development types used in the public workshops. Each Scenario assumes the same future network of highways and transit corridors (see Transportation Policy Plan, Jan. 2001), but coordinates land use with these networks to varying degrees. Finally, all three Scenarios accommodate the same increment of growth – 280,000 households and 360,000 jobs. Calthorpe Associates

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DEVELOPMENT ON AGRICULTURAL LANDS

around a shared public space. Homes can be placed on the soils most

The Current Plans Scenario develops significantly more agricultural

appropriate for septic tanks and drainage fields. The clustering of

land and prime agricultural soils than the Workshop Scenarios. The

homes saves infrastructure costs by reducing the length of roads and

agricultural land alone developed in the Current Plans Scenario is

utility lines. The remaining acres of each lot form a contiguous open

comparable to all of the new land developed in Workshop Scenario A,

space, in which 50 to 90 percent of the site can be preserved in its

and is nearly 10 percent more than all the new land developed in

natural or farmed state. Though Rural Cluster is considered as

Workshop Scenario B. In the Current Plans Scenario, nearly 57,000

“developed” land in the Scenarios, more land is actually conserved

acres (89 square miles) of prime agricultural soils were developed,

within areas designated Rural Cluster. Thus, a significant proportion

while only 34,000 (53 sq. miles) and 32,000 acres (50 sq. miles) are

of the 33 square miles of Rural Cluster in Workshop Scenario A and

developed in Workshops Scenarios A and B, respectively.

the 67 square miles in Workshop Scenario B remain undeveloped.

DEVELOPMENT ON AGRICULTURAL LAND AND PRIME AGRICULTURAL SOILS Natural Open Space (Activities Restricted) Active Open Space (Construction, fences, pets permitted) Building Site (Location & orientation restrictions)

RURAL CLUSTER

Common Open Space (Natural Features preserved where possible)

The Regional Workshop Scenarios incorporate a significant amount of rural cluster development – a form of conservation development in which more land is conserved than developed. Rather than parceling off agricultural land and ecologically-sensitive areas into uniformly large residential lots, this approach clusters homes on variable size lots

The above diagram illustrates the hierarchy of uses typical in rural cluster development

RURAL CLUSTER DEVELOPMENT

These examples of Rural Cluster Development emphasize the connection between clustered homes and the natural landscape. At left, homes are clustered around a central green, which is also accessible via trail. At right, homes face onto a preserved riparian corridor. Calthorpe Associates

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WALKABLE DEVELOPMENT The differences between each Scenario become more apparent in a comparison of specific land uses. The character of each Scenario is largely reflected in the extent to which walkable and auto-oriented development types are utilized. Walkable development – development with a mix of uses and an interconnected street network – is essential to livable communities that provide transportation choices, including driving, taking transit, walking and other modes. Auto-oriented development is often characterized by disconnected networks of streets, lower-density development and large-scale activity centers. While such activity centers are mixed-use, their scale and design are not conducive to walking.

WALKABLE DEVELOPMENT COMPARISON

Walkable development accounts for 25 percent of the households in the Current Plans Scenario. The Workshop Scenarios provide a greater diversity of housing and employment centers in walkable centers than the Current Plans Scenario. Walkable development accounts for 57 percent of households in Workshop Scenario A and 70 percent of households in Workshop Scenario B.

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RESIDENTIAL DENSITY

To more accurately depict the difference between each Scenario, the

The discussion of development scenario density incoporates both

incremental density can be divided into the Urban Service Area density

final and incremental figures. The final regional residential density*,

and the Rural Area density. The Urban Service Area Density measures

encompassing all existing development and new land to be developed

residential density within the region’s contiguous urbanized areas.

in the Scenario, does not vary significantly between the Scenarios. Thus,

The Rural Area density measures residential density outside this core

while the Regional Workshop Scenarios concentrate development along

of developed land. The Urban Service Area Density in the Current

centers and corridors and conserve natural resources, they do not

Plans Scenario is 4.3 dwelling units per acre. Due to greater reinvestment

significantly alter the all-encompassing final density. The Current Plans

and transit corridor development in the Regional Workshop Scenarios,

Scenario results in a final region-wide density of 1.32 dwelling units

the Workshop Scenario A Urban Service Area Density is 6.5 du/ac

per acre (du/ac) – near the 2000 residential density of 1.24 du/ac.

while that of Workshop Scenario B is 8.3 du/ac.

Regional Workshop Scenarios A and B result in slightly higher final

URBAN SERVICE AREA AND RURAL AREA DENSITIES

densities of 1.44 and 1.46 du/ac, respectively. Regional Densities (Dwelling Units per Residential Acre) Final Regional Density Incremental Regional Density Urban Service Area Density Rural Area Density

Current Plans 1.32 1.71 4.35 0.52

Workshop A Workshop B 1.44 1.46 3.32 3.59 6.79 8.35 0.92 1.29

The incremental density – the density of only newly developed land – does vary with each Scenario. The Current Plans incremental density is 1.71 du/ac. The Regional Workshop A incremental density is 3.32 du/ac, while that of the Regional Workshop Scenario B is 3.59 du/ac.

The Rural Area Density of 0.52 du/ac for the Current Plans Scenario

The incremental density of Regional Workshop Scenario B is most

reflects the widespread use of low-density estate and large-lot

consistent with the densities desired by most groups at the public

residential development. The Rural Area Density of .92 du/ac and

workshops.

1.29 du/ac in Regional Workshop Scenarios A and B reflect greater housing diversity and various single-family residential types in the

FINAL AND INCREMENTAL DENSITIES

Rural Areas.

The Urban Service Area Density was calculated on land within the red, inner border. The Rural Area density was calculated on the remaining land, outside of the border.

* Residential Density is equal to the number of dwelling units divided by the number of net residential acres. Calthorpe Associates

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REINVESTMENT

THE JOBS-HOUSING BALANCE

Reinvestment typically takes advantage of older, outmoded commercial

The jobs-housing balance is a meaningful way to gain a sense of how

and industrial areas and other underutilized lands, often surrounding

many people will commute to work, to or from where they will

transit corridors. In the Current Plans Scenario, 7 percent of households

commute, and how far they will have to commute. An unbalanced

and 17 percent of jobs are gained from reinvestment. The number of

jobs-housing ratio implies employees will be spending more time on

households from reinvestment doubles in Workshop Scenario A, to

roadways that may be better spent with their families or at work. One

14 percent, while 26 percent of jobs are gained from reinvestment. In

way to measure the regional jobs-housing balance is to compare the

Workshop Scenario B, 19 percent of households and 35 percent of

number of households living near a major concentration of jobs.

jobs were provided by reinvestment. Increased reinvestment is a key

Compared to the Current Plans Scenario increment, the Workshop

factor in the consequent reduction of development on sensitive

Scenario A growth increment contains roughly 30 percent more

environmental and agricultural areas in the Workshop Scenarios.

households located within 2 miles of the region’s largest employment

HOUSEHOLDS AND JOBS FROM REINVESTMENT

concentrations. Comparing Workshop Scenario B to the Current Plans Scenario, the difference is over 200 percent. The Regional Workshop Scenarios place a greater number of households near employment concentrations along transit corridors.

HOUSING MIX Recent Metropolitan Council studies have projected the demand for multi-family and single-family housing in the Twin Cities Metropolitan Region. Each Scenario meets this forecast to a different degree. The Current Plans Scenario over-supplies single-family households and under-supplies multi-family households by roughly 36 percent – more than 50,000 units. Workshop Scenario A meets the housing-type

Large Employment Concentrations in the Twin Cities Region

demand to a better degree, oversupplying single-family and undersupplying multi-family housing by approximately 15 percent.

HOUSEHOLDS NEAR EMPLOYMENT CONCENTRATIONS

Workshop Scenario B meets the single-family and multi-family housing demand forecast.

MEETING HOUSEHOLD DEMAND

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ACCESS TO PARKS AND T RAILS

ACCESS TO TRANSIT

Compared to the Current Plans Scenario, the Regional Workshop

Land use in the Scenarios is coordinated with the existing and planned

Scenarios place more households near regional parks and open space.

transit infrastructure to varying degrees. The Current Plans Scenario is

Within a 2.5 mile radius of Regional Parks, Workshop Scenario A

not necessarily oriented towards the planned regional transit network,

places 20 percent more households and Workshop Scenario B places

as this network was just emerging when most comprehensive plans

40 percent more households than the Current Plans Scenario. Within

were being completed. For example, the Current Plans Scenario places

a 5 mile radius, the Regional Workshop Scenarios both contain over

6,000 households within ¼ mile (walking distance) of planned light-

40 percent more households than the Current Plans Scenario. A

rail, express busways and other future transit corridors. More than

comparison of the households near regional and state trails also shows

13,000 households in Regional Workshop Scenario A and 23,000

great variation between the Scenarios. The households within ½ mile

households in Regional Workshop Scenario B are placed within the

of regional and state trails jump 150 percent between the Current

same area. Similarly, 40,000 households in the Current Plans Scenario

Plans Scenario and Regional Workshop Scenario A (from 13,000 to

increment are added within ¼ mile of existing bus stops, while 60,000

25,000 new households). The increase is more than the 200 percent

households and 90,000 households are placed within the same area in

from the Current Plans Scenario to Workshop Scenario B, which places

Regional Workshop Scenarios A and B. Increased transit accessibility

32,000 new households Within ½ mile of regional and state trails.

noticeably affects automobile usage, as described in the following section.

HOUSEHOLDS

AND

EMPLOYEES N EAR EXISTING TRANSIT

HOUSEHOLDS

AND

EMPLOYEES NEAR PLANNED TRANSIT

Regional Parks and Trails and State Trails

HOUSEHOLDS NEAR PARKS AND TRAILS

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TRANSPORTATION

effect – in the Regional Workshop Scenarios. Regional Workshop

Transit trips increase while automobile use generally decreases as the

Scenario A reduces the Current Plans Scenario output of CO by 66

Scenarios become more walkable and transit-oriented. Development

percent. Regional Workshop Scenario B reduces the Current Plans CO

in Workshop Scenario A provides for 185 percent more trips on transit

output by 92 percent.

than the Current Plans Scenario. In Workshop Scenario B, transit trips

EMISSIONS COMPARISON

increased by 283 percent when compared to the Current Plans Scenario. For Workshop Scenario A, this represents an increase of more than 64,000 trips and 430,000 passenger miles. For Workshop Scenario B, transit trips increase by more than 114,000 trips and passenger miles 606,000 over the Current Plans Scenario. Comparing the Regional Workshop Scenario increments to that of the Current Plans Scenario shows dramatic differences in Vehicle Trips, Miles, and Hours. Regional Workshop Scenario A reduced Vehicle Trips by 11 percent and Vehicle Miles by 13 percent - this translates into a reduction of over 204,000 Vehicle Trips and 2.2 million Vehicle Miles each day. Workshop Scenario B reduces these figures to an even greater degree, slashing Vehicle Trips by more than 265,000 and Vehicle

PUBLIC INFRASTRUCTURE COSTS

Miles by more than 3 million. Vehicle hours in congestion and free-

The cost of infrastructure further differentiates the consequences of

flow are also significantly reduced in both Workshop Scenarios. Such

the three Scenarios. The totals below incorporate the costs of regional

reductions cut person hours in vehicles by 130,000 hours and 194,000

sanitary sewer facilities, local water, sewer and stormsewer facilities

hours each day in the Regional Workshop Scenarios A and B, respectively.

(WSS), local roads, the regional transit network and regional highways.

AUTOMOBILE USE STATISTICS

Since the Current Plans Scenario develops the greatest land area with the greatest number of road-miles, its infrastructure costs are consistently higher, especially the local road and WSS facility expenditures. Regional Workshop Scenario A reduces the Current Plans infrastructure costs by $2.5 billion. Regional Workshop Scenario B reduces infrastructure costs by $3 billion.

INFRASTRUCTURE COST COMPARISON

AIR QUALITY Air quality indicators substantially improve as automobile use decreases and transit ridership increases. The Workshop Scenario A increment reduces the emissions produced in the Current Plans Scenario increment by 53 percent. Workshop Scenario B reduces emissions by 74 percent – more than 70 tons per day. Most notable is the reduction of Carbon Monoxide (CO) – a major contributor to the greenhouse Calthorpe Associates

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