2: COMPLETE STREETS The second approach integrates green stormwater management into a broader reconfiguration of the streetscape. Several of the Green Infrastructure systems in the first approach are replaced with largely structural soils systems that better support tree growth and longevity in addition to managing stormwater. These soils are added under permeable sidewalks, significantly increasing the growing space for the trees and the water absorption capacity of the streetscape as a whole. In this scenario the trees are likely to reach both greater life-expectancy and size. Reducing road surface further reduces the amount of stormwater runoff. Road widths are narrowed following regional and national Complete Streets strategies to reduce impervious surface area, slow traffic, and encourage foot traffic and general street life. Bump-outs increase the amount of growing space and create narrow vehicular entries and chicane patterns to reduce traffic speed in residential areas. Porous pavement in the on-street parking areas further enables on-site infiltration. Outline of the Design Pages The two design approaches are displayed on the following pages next to each other on a block-by-block basis for easy comparison. Each two-page spread contains a plan view, a section view, street dimensions, rough cost estimates, and the number of trees included.
Pros: • Integrates effective long-term stormwater management with greening as an urban revitalization strategy. • Impervious surface area is significantly decreased, resulting in less runoff. • The capacity to deal with both volume and filtration is greatly increased. • Tree size and longevity are significantly increased, resulting a greater impact on the urban environment (including air quality, heating/cooling costs) over time. • Encourages foot traffic and street life, a possible incentive for potential investors in the mill properties and downtown. • Can be implemented on a block-by-block basis and/ or integrated with the sewer separation project. Cons: • Changes street characteristics people are familiar with. • Relatively extensive. • May require moving some underground utilities.
Left page describes the Green Streets approach (number 1) and highlights details pertinent to the particular block. Right page describes the Complete Streets approach (number 2) applied to the same block.
CHICOPEE GREEN STREETS DESIGNS
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