REPORT DOCUMENTATION PAGE 



Form Approved 

 OMB No. 0704-0188 



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 Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503. 



1. AGENCY USE ONLY (Leave blank) 



2. REPORT DATE 



September 1998 



3. REPORT TYPE AND DATES COVERED 



Final report 



4. TITLE AND SUBTITLE 



Design for Navigation Improvements at Nome Harbor, Alaska; Coastal Model 

 Investigation 



6. AUTHOR(S) 



Robert R. Bottin, Jr., Hugh F. Acuff 



5. FUNDING NUMBERS 



7. PERFORMING ORGANIZATION NAME(S) AND ADDRESSES) 

 U.S. Army Engineer Waterways Experiment Station 

 3909 Halls Ferry Road 

 Vicksburg.MS 39180-6199 



8. PERFORMING ORGANIZATION 

 REPORT NUMBER 



Technical Report CHL-98-28 



9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESSES) 

 U.S. Army Engineer District, Alaska 

 P.O. Box 898 

 Anchorage, AK 99506-0898 



10. SPONSORING/MONITORING 

 AGENCY REPORT NUMBER 



11. SUPPLEMENTARY NOTES 



Available from National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. 



12a. DISTRIBUTION/AVAILABILITY STATEMENT 



Approved for public release; distribution is unlimited. 



12b. DISTRIBUTION CODE 



13. ABSTRACT (Maximum 200 words) 



A l:90-scale (undistorted) three-dimensional coastal hydraulic model was used to investigate the design of proposed 

 navigation improvements at Nome Harbor, Alaska, with respect to wave, current, and shoaling conditions at the site. The 

 model reproduced about 3,350 m ( 1 1 ,000 ft) of the Alaskan shoreline, the existing harbor and lower reaches of the Snake 

 River, and sufficient offshore bathymetry in the Norton Sound to permit generation of the required experimental waves. The 

 model was used to determine the impacts of a new entrance channel on wave-induced current patterns and magnitudes, 

 sediment transport patterns, and wave conditions in the new channel and harbor area, as well as to optimize the lengths and 

 alignments of new breakwaters and causeway extensions. A 24.4-m-long (90-ft-long) unidirectional, spectral wave generator, 

 and automated data acquisition and control system, and a crushed coal tracer material were utilized in model operation. It was 

 concluded from study results that: 



a. Existing conditions are characterized by rough and turbulent wave conditions in the existing entrance. Very confused 

 wave patterns were observed in the entrance due to wave energy reflected off the vertical walls lining the entrance. Wave 

 heights in excess of 1 .5 m (5 ft) were obtained in the entrance for typical storm conditions; and wave heights of almost 3.7 m 

 (12 ft) were obtained in the entrance for 50-year storm wave conditions with extreme high-water level (4 m (+13 ft)). 



b. Wave conditions along the vertical-faced causeway docks were excessive for existing conditions. Wave heights in 

 excess of 3.7 and 2.7 m (12 and 9 ft) were obtained along the outer and inner docks, respectively, for typical storm conditions; 

 and wave heights of almost 7 and 5.8 m (23 and 19 ft) were recorded along these docks, respectively, for 50-year storm wave 

 conditions with extreme high-water levels. (Continued) 



SUBJECT TERMS 



Breakwaters 

 Causeways 

 Harbors, Alaska 

 Hydraulic models 



Navigation 

 Nome Harbor, Alaska 

 Sediment transport patterns 

 Wave-induced currents 



Wave protection 



15. NUMBER OF PAGES 



153 



16. PRICE CODE 



17. SECURITY CLASSIFICATION 

 OF REPORT 



UNCLASSIFIED 



18. SECURITY CLASSIFICATION 

 OF THIS PAGE 



UNCLASSIFIED 



19. SECURITY CLASSIFICATION 

 OF ABSTRACT 



20. LIMITATION OF ABSTRACT 



NSN 7540-01-280-5500 



Standard Form 298 (Rev. 2-89) 



Prescribed by ANSI Std. Z39- 1 8 

 298-102 



