Water Protection and Sustainability Branch

Evaluating Long-term Well Capacity for a Certificate of Public Convenience and Necessity

A Guidance Document

1 Introduction
2 General Requirements and Special Conditions for Well Testing

2.1 General Well Testing Requirements
2.2 Special Conditions

3 Estimating Long-term Well Capacity

3.1 Short-term Pumping Tests
3.2 Extrapolating Drawdown to 100 Days
3.3 Available Drawdown in the Well
3.4 Calculating the Well Capacity
3.5 Assessing the Recovery Data
3.6 Other Types of Assessments to Determine Long-term Capacity

4 Marginal Well Capacity and the CPCN Process
5 Long-term Monitoring and the CPCN Process
6 References

Appendix A: Definitions and Interpretation
Appendix B: Checklist for Pumping Test Reports in Support of Certificate of Public Convenience and Necessity

Acknowledgements:

• Dr. Diana Allen, Assistant Professor of Earth Sciences at Simon Fraser University,
• Ann Badry, Hydrogeologist of Pacific Hydrology Consultants Ltd.,
• Bruce Ingimundson, Hydrogeologist of Thurber Engineering Consultants,
• Dr. Gilles Wendling, Hydrogeologist of Levelton Engineering, and
• Bill Worobets and Neil Morrison of the Water Management Branch

provided valuable comments to the initial draft of this document.
Editing of this document was done by Eakins Consulting Ltd.

Canadian Cataloguing in Publication Data

Main entry under title:
Evaluating long-term well capacity for a certificate of public convenience and necessity:
a guidance document
Includes bibliographical references: p.
ISBN 0-7726-4019-X

1. Wells Testing. 2. Ground Water Flow Measurement. 3. Wells Standards British Columbia. I. British Columbia. Water Management Branch.

TD405.E92 1999 628.1'14 C99-960328-0

Evaluating Long-Term Well Capacity for a Certificate of Public Convenience and Necessity
is available at:

Ministry of Environment
Water Protection and Sustainability Branch
Ground Water Section
395 Waterfront Crescent
Victoria, B.C., V8T 5K7

Introduction

This document provides guidance in the evaluation of long-term well capacity from well tests in support of a Certificate of Public Convenience and Necessity (CPCN). It provides technical background and rationale for the general requirements and special conditions for well testing. The document also presents the general method the Ground Water Section, Water Management Branch, uses to estimate long-term well capacity and therefore may give technical insight to reviewing well test reports. It is intended for professional engineers, hydrogeologists and other consultants involved with the development of ground water supplies for private water utilities regulated under the Water Utility Act and the Utilities Commission Act. Definitions of terms directly related to well tests and their significance in the interpretation of pump test data are presented in Appendix A.

Before a ground water source can be developed into a community supply, well performance and aquifer capabilities must be adequately assessed. The well testing and presentation of ground water information must follow certain procedures for submission to the Comptroller of Water Rights for a CPCN under the Water Utility and Utilities Commission Acts. Guidelines for testing and reporting for community well supplies for a CPCN are outlined in Appendix 9 of the publication, Water Utilities - Guide to Applying for a Certificate of Public Convenience and Necessity (CPCN), 1998 ¹. The intent of these guidelines is not to lay down rigid rules, but to avoid unnecessary delays or re-tests at the applicant's expense due to inadequate test procedures or report presentations. The Comptroller is prepared, on request, to review the requirements for any particular case with the applicant, or the applicant's professional ground water consultant, prior to the well test.

PLEASE NOTE: This document is NOT meant to be a "recipe book" for well testing and assessment nor is it meant to replace professional experience nor instruct qualified professionals how to evaluate pump test data. The consultant should always rely on information on the hydrogeology of the site and data from the actual well tests to assess the proposed community well supply. The design of pumping tests and evaluation of pump test data should always be carried out under the supervision of a professional hydrogeologist ².

________________________________________

¹ Appendix 9 also replaces Appendix No. 5, Community Water Supply Wells - Ground Water Reports and Well Tests in Support of a Certificate of Public Convenience and Necessity in Guidelines for Minimum Standards in Water Well Construction, Province of British Columbia (1982).

² A professional hydrogeologist is a person who is registered as a Professional Geoscientist (P. Geo.) or Professional Engineer (P. Eng.) with the Association of Professional Engineers and Geoscientists of British Columbia with competency in the field of hydrogeology.