Development and Application of a Low Impact Development (LID)-Based District Unit Planning Model

Abstract

Abstract:The purpose of this study was to develop a low impact development-based district unit planning (LID-DP) model and to verify the model by applying it to a test site. To develop the model, we identified various barriers to the urban planning process and examined the advantages of various LID-related techniques to determine where in the urban development process LID would provide the greatest benefit. The resulting model provides (1) a set of district unit planning processes that consider LID standards and (2) a set of evaluation methods that measure the benefits of the LID-DP model over standard urban development practices. The developed LID-DP process is composed of status analysis, comprehensive analysis, basic plan, and sectoral plans. To determine whether the LID-DP model met the proposed LID targets, we applied the model to a test site in Cheongju City, Chungcheongbuk-do Province, Republic of Korea. The test simulation showed that the LID-DP plan reduced nonpoint source pollutants (total nitrogen, 113%; total phosphorous, 193%; and biological oxygen demand, 199%); reduced rainfall runoff (infiltration volume, 102%; surface runoff, 101%); and improved the conservation rate of the natural environment area (132%). The successful application of this model also lent support for the greater importance of non-structural techniques over structural techniques in urban planning when taking ecological factors into account.Keywords: low impact development; urban planning; district unit planning; LID-based district unit planning model; land-use planning

Innovations in Best Practices: Approaches to Managing Urban Areas and Reducing Flood Risk in Reggio Calabria (Italy)

“…LID is a management approach that focuses on the conservation and/or the recovery of pre-development water cycle conditions through various strategies and formal elements [25] that mimic the original water cycle functions, mainly in terms of infiltration and retention. These technologies not only include structural techniques but also non-structural ones that support the functions of the water cycle [34,35].…”

“…They are also indicated for highly urbanized areas as they are usually micro-scale and decentralized facilities [31,39]. Some studies report that LID measures have other positive effects such as improving public health, ecosystem diversity, increasing land value, and reducing rainfall runoff [25]. Combining LID measures with urban design can also bring about the possibility of retrofitting degraded urban areas as well as using green open spaces to improve environmental connections.…”

“…Considering that the study area is densely urbanized, and heavy structural measures are of difficult implementation, LID measures of small application scale were chosen to reduce part of the recurrent flooding in Piazza della Pace. These measures aim to facilitate the recovery of part of the pre-development water cycle conditions through various strategies and elements that mimic the original water cycle functions, mainly in terms of infiltration and retention [25].…”

“…Some of the most common best practices (structural and non-structural) can be summarized as: flood zoning [22,23], LID (low impact development) controls [24,25], relocation of structures and infrastructures at risk [26], re-balancing of the sedimentary cycle, and reorganization of city mobility through early warning systems [27,28].…”

Decision-Support System for LID Footprint Planning and Urban Runoff Mitigation in the Lower Rio Grande Valley of South Texas

“…Very few studies have attempted to develop a region-specific decision-support framework to assess the LID transformation in a small-scale or commercial development boundary to reveal both maximum ecosystem services and minimum costs. Still, there is a lack of a well-established tool to enforce the local drainage policy in optimal selection and evaluation of combined BMP scenarios for maximizing hydrologic benefits in urban development [32,36,37]. The proper selection of a BMP or BMPs in series through innovative planning, management, and engineering approaches will not only benefit communities but will also protect the water quality and ecosystems of the watershed [7].…”