HomeMy WebLinkAboutSUS430MEMORANDUM State of Alaska
TO
FROM
Jon Ferguson
Project Manager
Alaska Power Authority
DATE
FILE NO
TELEPHONE NO
Allen E. Bingha~~
Acting Aquatic Studies Coordinator
Su Hydro Aquatic Studies
SUBJECT
Nowember 30, 1984
02-84-13.06
03-84-7.10-3.2
Draft Technical Memorandum
on 1984 Salmon Passage
Validation Studies
(Task 35)
This draft memorandum presents information to fulfill Task 35 which addresses
the Passage Validation Studies (PVS) which were conducted duri:ng the 1984
open water field season by the Alaska Department of Fish and rarne (ADF&G)
Susitna Hydro Aquatic Studies Team. Review comments on the memorandum should
be submitted to this office by December 11, 1984. A meeting will 1 be held for
interested project participants on December 13. 1984 (1) to discuss comments
received and (2) to determine if the revisions in this memorandum warrant a
reevaluation of previously established discharges and loca 1 flows required
for successful and unsuccessful salmon passage at slough and side channel
sites. The second topic will be advised in a forthcoming memorandum as it is
not programmed in our FY 85 budget.
Draft Technical Memorandum
on 1984 Salmon Passage
Validation Studies
INTRODUCTION AND OBJECTIVES
Preliminary field studies of adult chum salmon (Oncorhynchus keta) passage
conditions in slough and side channel spawning habitats of the middle Susitna
River were conducted during the 1982 (ADF&G 1983: Appendix B) and 1983
(Sautner et al. 1984) ~~en water field seasons. These studies evaluated the
influence of selected channel geometry and hydraulic characteristics on chum
salmon passage into and within these habitats. These studies provided the
Ferguson 2 DRAFT /11/30/84
basis for establishing interim salmon passage criteria for estimating the
mainstem discharges and related local slough flows required to provide
successful and unsuccessful passage corh~itions for chum salmon migrating into
and within these habitats.
A field Passage Validation Study (PVS) was undertaken during the 1984 open
water field season to verify or r~fine interim fish passage criterh and flow
requirements established previously as recommended in Sautner et al. (1984).
That is, salmon passage criteria curves developed from 1983 data were based
on a review of limited field data and observations collected during 1982
combined with the professional judgement of fisheries biologists and
hydraulic engineers. The field data available for the initial development of
these curves in 1983 were limited. Therefore, it was necessary to obtain
additional field data in 1984 to validate the 1983 curves and, if necessary,
refine them to more closely represent natural passage conditions for chum
salmon.
Accordingly, the 1984 field data were collected to address two main
objectives:
1) Verify or refine the 1983 passage critPria curves (Sautner et al
1984) developed from 1982 and 1983 data which describe passage
conditions for chum salmon into and within slough and side channel
habitats in the middle reach of the Susitna River; and,
2) If necessary, refine the estimates of mainstem discharges and local
flows which provide successful and unsuccessful passage conditions
for chum salmon into and within all slough and side channel sites
previously evaluated.