Alternative Stormwater Design Within the Public Right-of-Way, A Residential Preferences Study

by Melanie Mills

Chairperson of the Supervisory Committee
Assistant Professor Kristina Z. Hill

2002

This study was carried out to assess visual preference for residential street edge retrofit designs, including “naturalistic stormwater structures” and specific street edge elements. Information was gathered regarding residents’ expectations and/or preferences in relation to the aesthetics, functionality, economics, maintenance, and environmental implications of a street edge retrofit along their street. The study area was limited to the informal drainage areas of North Seattle. In particular, those residential areas where stormwater flows above ground through a system of ditches and culverts, and where streets do not include improvements such as curb and gutter or sidewalks. The study area includes two of Seattle’s priority urban watersheds, those of Pipers and Thornton Creeks.

The study used computer-simulated images to show the same street with different street edge re-design alternatives along a continuum, starting with a typical formal design and moving toward a naturalistic design. Sixty homeowners living within the study area participated in the survey. Results indicated a preference for naturalistic street edge re-designs. Patterns of preference were seen for specific street edge elements and functions (e.g., landscaping, division between street and other uses, stormwater channel, sidewalks) and these extended across aesthetic image preferences. Additional patterns seen in residents’ responses included: (a) a willingness to contribute labor, maintenance, and a limited amount of financial support for a street edge retrofit on their block; (b) a level of consensus regarding the responsibility for various maintenance tasks (e.g., City or homeowner); and (c) an expressed level of importance for environmental benefits resulting from street edge re-designs, regardless of demographic factors.