Electrical Power for Valdez and the Copper River Basin-1981

gages at Lowe River near Valdez, Lowe River in Keystone Canyon nearValdez, and Solomon Gulch near Valdez are shown on Table A-l. Thestreamflows for Klutina River at Copper Center and Tonsina River atTonsina are given in Tables A-2 and A-3, respectively.The gage at Solomon Gulch was on the right bank at the tidewater, 1/2mile downstream from a small lake and about 3 miles south of Valdez. Therecords that are available are July to December 1948 and October 1949 toSeptember 1956. The average annual runoff is 104,300 acre-feet per yearor 144 cfs.The gage on the Lowe River in Keystone Canyon near Valdez is locatedon the left bank, 500 feet south of the south entrance to RichardsonHighvJay tunnel in Keystone Canyon. The records that are available areOctober 1974 to the current year. The average annual runoff is about1,200 cfs. The other Lowe River gage (Lm"e River near Valdez) wasupstream from this one about 4 miles. The gage was discontinued inSeptember 1974.The Klutina River gage was near the left bank on the downstream sideof the RiChardson Highway bridge, 0.7 mile south of Copper Center.Records are available from October 1949 to June 1967 and July 1970 toSeptember 1970. The mean streamflow is 1,670 cfs.The Tonsina River gage is near the right bank on the downstream sideof the RiChardson Highway bridge at Tonsina. Recorded streamflows extendfrom October 1950 to September 1954 and from October 1955 to September1978. The mean annua 1 flow is 836 cfs.txtension of Streamflow Records:Extension of t'le streamflow records for Solomon Gulch and Lowe Riverwas performed by linear correlation with the long term records of Power(reek near Cordova. In an attempt to observe visual relations betweenthe stations, the respective monthly strEamflows for the two stationswere plotted against the correlative Power Creek monthly streamflows, asshown in Table A-4. Depending on the shapes of the relationshipsohserved, the data were split into time groups ranging from 1 month to 3months. After transformation, a linear regression analysis was performedfor each data group and, based on the correlation coefficients andstandard errors of estimate, a relationship for each group of data wasadopted for streamflow extension.In general, there was good correlation for the months of Aprilthrough December. The winter months of January, February, and March weregrouped together and still had a low correlation coefficient. It may beexplained by the lowflow characteristics of Power Creek which did notdl"scribe the same 1m" flow on the other two gages. The equation on theLowe River for August was adjusted since it was not consistent with theLA-6