Moreau, M.; Nokes, C.; Cameron, S.G.; Hadfield, J.; Gusyev, M.A.; Tschritter, C.; Daughney, C.J. 2014 Capture zone guidelines for New Zealand. Lower Hutt, N.Z.: GNS Science GNS Science report 2013/56 47 p.
Abstract: For regional councils and unitary authorities to manage effectively the land and water resources for which they have responsibility, they require information about how decisions regarding land use may affect the quality of water bodies. Key to understanding how land use decisions may influence water quality is knowledge of the area of land from which a water body, or feature, receives its water – the capture zone – and potential contamination sources within this area. This Guideline document, and the associated technical document (Moreau et al., 2014a) assist in the delineation of protection and capture zones for wells, springs and lakes or wetlands with groundwater contribution. Apart from regional councils and unitary authorities, potential users of the Guidelines include: territorial authorities, water suppliers (many of who will be territorial authorities), consultants and research organisations. The associated technical report provides more in-depth discussion of the use of delineation methods and the justification for zone thresholds. It also includes five New Zealand case studies for a range of hydrogeological settings. The Guideline’s purpose is to provide information and guidance in selecting an appropriate method for delineating the protection and/or capture zones for a given setting and purpose. A set of methods, ranging from unsophisticated desktop methods through to numerical modelling, is discussed to address varying user needs and constraints. These include precision requirements and restrictions on data and resource availability. Uncertainty in delineating zones is also discussed and, where applicable, guidance on either qualifying or quantifying the uncertainty is given. The Guidelines lead the user through the process of deciding which method or methods are suitable for meeting their needs. It also provides equations and resources to undertake delineation. A worked example and reporting template, is provided to show the practical application of manual methods in zone delineation. (auth)