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mene

WATER SHORTAGE RESPONSE PLAN - PRC

DISCUSSION PAPER

Introduction

Concern over: the ability of the GVWD's supply sources to meet high demands
for water over an extended period of drought has led to the need to develop

a plan to deal with such an event. The experience of the summer of 1990,-

indicates that such a plan is required to be in place for the summer of 1991

high water usage season, expected to begin in July. Improvements made to
ases in the outlet capacity of Palisade and

the transmission system and incre

Burwell Lakes are expected to improve the supply situation somewhat for
1991. However, there has been an increase in. population and areas. served

over 1990 levels and statistically, the 1990 drought was less severe than

the 100-year design case being proposed due to the occurrence of

intermittent’ periods of rainfall...

At this time, a Water Shortage Response Plan (WSRP) is being proposed to
deal with drought-induced depletion of storage. It is expected that the
WSRP will be expanded in future to encompass shortages resulting from |
emergencies such as failure of major system components. This later stage of
development of the WSRP will be accomplished as part of the Comprehensive |
Regional Water Supply Study, since that study will address the risk of
failure of key system components and the effect on supply capability.

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Background

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The GVWD relies on water from three sources Capilano, Seymour and Coquitlam.
The District has full use of the storage at Capilano and Seymour but at. a
Coquitlam, B.C. Hydro has licences for the majority (approximately . |
90 percent) of the inflow and all of the storage. The GVWD is licenced to
withdraw up to 50 million. gallons per day (MGD) from Coquitlam Lake and by.
agreement with B.C. Hydro may purchase up to an additional 100 NGD (annual
average) or up to a total of 260 MGD peak day. Peak day demand on the
regional supply system was 437 MGD on July 30, 1990. -

“Due to the configuration of the supply system, about 80. percent of the.
regional demand is supplied from Seymour and Capilano together, with

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