GIS is a digital cartographic tool capable of creating, integrating, storing, editing, analysing, sharing and displaying geographically referenced information. It allows users to create queries, analyse spatial information as well as edit and manage data with the final product being the creation of maps to aid in visual interpretation. Digby Wells has fully functional GIS capabilities and makes use of industry leading GIS software.
The use of GIS in the environmental industry provides holistic visualisation. GIS saves time, decreases costs, improves accuracy, and provides solutions to problems resulting in sound environmental management and planning.
Social GIS Solutions
The application of GIS in social sciences involves making use of aerial imagery and GPS technology. Applications include providing solutions for resettlement plans, community surveys and route selection for linear developments. For resettlement projects, GIS can be utilised for the evaluation of current and host sites; household, asset and agricultural surveys; archaeological assessments; and town layouts.
3D Modelling & Visualisation
A Digital Elevation Model (DEM) created from point and/or contour data forms the basis of all 3D modelling. 3D models can be analysed to determine slope and aspect models, cut and fill, volume calculations, viewshed models, line of sight, observer points and profile graphs. 3D models are utilised for Visual Impact Assessments, Closure Cost Calculations, Rehab Plans, Slope Stability, Decant Scenarios, and Catchment Delineation.
Visual Impact Assessments
A Visual Impact Assessment (VIA) is a specialist study performed to identify the visual impacts of a proposed project on the surrounding landscape. A viewshed (geographical area) is created and analysed in GIS, in terms of the topography, within which a particular feature will be visible.
Spatial Management Plans
Spatial Management Plans make use of interactive mapping software. The purpose of these plans is to facilitate the management of the environment by ensuring that management measures are site and feature specific. These plans assist in the implementation of Environmental Management Plans (EMPs). Spatial Management Plans are easy to use, accessible to multiple users, provide basic GIS capability, and facilitate auditing.
Remote Sensing - Thermal & Hyperspectral Sensing
Remote sensing is the process of obtaining data in a remote location like an aircraft or satellite. Thermal remote sensing captures radiation emitted from matter in the thermal infrared region of the spectrum and is useful for identifying spontaneous combustion.
Hyperspectral remote sensing is the acquisition of light reflections from the earth, and is used to identify environmental features such as alien vegetation and pollutants; it can also be used to determine vegetation health.
Air Quality Assessments
Dust is captured on-site using either single bucket or multidirectional samplers and then analysed in a reputable laboratory. The results are then interpreted enabling an assessment of the baseline conditions prior to construction, in order to determine the potential impacts.
Dispersion models then compute ambient conditions as a function of source configurations, emission strengths and meteorological characteristics, thus providing a useful tool to ascertain the spatial and temporal patterns in the ground level concentrations arising from the emissions of various sources. Increasing reliance has been placed on concentration estimates from models as the primary basis for environmental and health impact assessments and emission control requirements.
Noise Impact Assessments
Baseline noise monitoring is conducted prior to development. This is then compared to the expected noise from the proposed activities and is used to assess the potential noise impacts. Noise Impact Assessments identify potential noise impacts, and provide mitigation measures and a recommended noise monitoring programme.