Because quality and availability
vary over time, historical record is
necessary to predict whether the
water will be suitable. Such records
are not available for most
waters, however, and changes in
water temperature, chemical composition,
and water availability
caused by unusual weather events
cannot be predicted by records.
The best advice is to use common
sense and avoid those waters that
may become unsuitable for use
during the time the hatchery is in
operation.