SUSTAINABLE SITE DESIGN:
The purpose of sustainable site planning is to integrate design and construction strategies by modifying both site and building to achieve greater human comfort and operational efficiencies. It charts appropriate patterns of use for a site while incorporating construction methods that minimize site disruption and the expenditure of financial and building resources. The process is based upon the premise that any landscape setting can be analyzed and studied as a series of interconnected geological, hydrological, topographic, ecological, climatological, and cultural features and systems. Selecting a building site begins the process of calculating the degree of resource use and the degree of disturbance of existing natural systems that will be required to support a building’s development.
SITE ANALYSIS AND ASSESSMENT:
Site assessment is a process that examines the data gathered and identified in the site analysis, assigns specific site factors to hierarchies of importance, and identifies, where possible, interactive relationships.
Technical site data –
Geographical latitude (solar altitude) and microclimate factors, such as wind loads—
Affect building layout, including solar orientation and location of entrances, windows.
Topography and adjacent landforms—Influence building proportions, wind loads, drainage strategies, floor elevations, and key gravity-fed sewer-line corridors.
Groundwater and surface runoff characteristics— determine building locations as well as natural channels for diverting storm runoff and locations of runoff detention ponds
Solar access—Determines position of building to take maximum advantage of natural solar resources for passive solar heating, day lighting, and photo voltaic.
Ai r-movement patterns, both annual and diurnal— particularly influence sitting of multiple structures to avoid damming cold moisture-laden air, or blocking favorable cooling breezes during periods of overheating. Properly measured wind loads and pressure differentials are essential for designing interior air-handling systems or use of passive solar cooling strategies.
Soil texture and its load-bearing capacity—Determine building location on the site and the type of footing required. Identify site-grading processes by the soil’s potential for erosion by wind, water, and machine disturbance.
Parcel shape and access—Affect a site’s capacity to accommodate a proposed development, even if its size and environmental\ factors are favorable. Potential access points should not burden lower-density or less compatible adjacent land use. Zoning setbacks and easements can also affect development potential.
Neighboring developments and proposed future developments—Affect proposed project and may lead to requisite design changes.
Analyze specific characteristics of climate zones: Climate has specific characteristics requiring mitigation, augmentation, and exploitation; there are 5 climatic zones in India.
Analyze the site’s existing air quality: Most state require an environmental impact assessment (EIA) outlining the potential negative impacts of a proposed development and how they might be alleviated. Site planning requires two kinds of air-quality analysis regarding: (1) assessment of the existing air quality of the site to determine the presence of noxious chemicals and suspended particulates, and (2) projection of the negative consequences (if any) of the proposed development on existing air quality. In primarily commercial or industrial areas, poor air quality should be a key factor in determining site suitability and use, especially for such facilities as schools, parks, or housing for seniors. Testing should anticipate seasonal or diurnal wind patterns to make certain that the worst possible case is tested.
Perform soil and groundwater testing: Perform soil tests to identify the presence of chemical residues from past agricultural activities (arsenic, pesticides, and lead); past industrial activities (dumps, heavy metals, carcinogenic compounds and minerals, and hydrocarbons); and any other possible contamination either on or in the vicinity of the subject site.
Test soil suitability for backfills, slope structures, infiltration: The native soil should be tested to determine bearing, compactability, and infiltration rates, and, in turn, structural suitability and the best method for mechanical compaction (i.e., clay soils require non-vibrating compaction and non-erosive angles of repose for cut-and-fill slopes).
Evaluate site ecosystem for existence of wetlands and endangered species: Preservation and restoration strategies require thorough economic analysis, specialized expertise, and sound baseline data gathered through both remote and on-site sensing methods.
Examine existing vegetation to inventory significant plant populations: This will enable the developer or owner to later specify vegetation that is susceptible to damage during construction, so that protective measures can be developed and implemented.
Map all natural hazard potentials (such as winds, floods, and mudslides): Historic flood data, wind-damage data, and subsidence data should be mapped along with current annual wind and precipitation data.
Diagram existing pedestrian and vehicular movement and parking to identify Patterns: Existing traffic and parking patterns in areas which are adjacent to or near the site may need consideration in relation to proposed building design and site circulation patterns.
Review the potential of utilizing existing local transportation resources: Explore the sharing of existing transportation facilities and other resources, such as parking and shuttles, with existing institutions. This can lead to greater site efficiencies.
Identify construction restraints and requirements: Special construction methods may be required because of local soil condition, geology, earth-moving constraints, and other site-specific factors and constraints.
Infrastructural data –
Analyze site for existing utility and transportation infrastructure and capacity: Existing infrastructure should be analyzed for integration into the building and facilities.
Historical Data –
Review architectural style of the area for incorporation into building: If desirable, the architectural style that is historically predominant in an area can be reflected in the building and landscape design, enhancing community integration.
Identify topographic and hydrological impacts of proposed design and building use: Measure cut-and-fill potential and assess potential for erosion, siltation, and groundwater pollution.
Develop general area takeoff and overall building footprint compatibility with site: For example, measure total site coverage of impermeable surfaces to determine thresholds of run-off pollution potential (i.e., over 20 percent impermeable coverage of gross site requires mitigation to clean storm water before it enters drainage system off-site). Footprint should also maximize site efficiencies with regard to required road, utility, and service access.
Identify alternative site design concepts to minimize resource costs and disruption: Develop several alternatives to explore optimal pattern with regard to factors such as grading and tree-clearing consequences and resulting infrastructure costs.
Review financial implications of site development, building, and projected maintenance costs: Total cost of the project must factor in ongoing costs associated with the site design, development, and operations, as well as hidden embodied energy costs associated with specific materials.
Develop matrix of use and site compatibility index: Each site may be assessed to reveal its development compatibility index with regard to a specific type of development. This index may reveal a pattern of incompatibilities thereby specific appropriate mitigation measures are undertaken.
Courtesy: Nicholas T. Dines, author.