181 

 G 18.2 TROUT CREEK (Gibraltar lake) 



LOCATION: 59°22'5^" N. l-^h^hl'DO" W. 



PREVIOUS NAMES OR NUMBERS: Al+a 



U.S.G.S. MAP: Iliamna, 1:250,000; Iliamna B-5, 1:63,360 



PHYSICAL DESCRIPTION 



TOTAL LENGTH: 6.1 miles 



LENGTH ACCESSIBLE TO SAIMON: 6.1 miles 



AVERAGE WIDTH: 12' RANGE: 10 '-15' 



AVERAGE DEPTH: 12" RANGE: 8"-30" 



TOTAL ACCESSIBLE SPAWNING AREA: i+3,076 square yards (8.9 acres) 



POTENTIAL SPAWNING AREA: 10^, U,356 sqmre yards (0.9 acre) 



BOTTOM QUALITY: 10^ <l/8", 20fo l/8"-3", 30/0 3"-12". Good gravel in lower 

 0.5 mile, much large rock beyond. Bottom unstable. 



WATERSHED: 33 square miles. A glacial valley through open rolling hills, 

 dense willow, alder, and birch thickets along stream. Subject to 

 occasional flood. Source: Emerald lake. 



GRADIENT: 86 '/mile 



WATER VELOCITY: 2.0 fps 



FLOW: 20 cfs (Aug. 6, I962). Measured RANGE: 



just above mouth, normal summer 

 flow. 



AIR TEMPERATURE: 22.0° C. (Aug. 6, I962) 



WATER TEMPERATURE: 11.0° C. (Aug. 6, I962) 



POOLS AND RIFFLES: 



