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PART IV: TESTS AKD RESULTS 



Base Tests 



3^. Base tests, or tests of existing prototype conditions^ are 

 made in connection with hydraulic model studies to provide a direct basis 

 for evaluating the results of subsequent tests incorporating proposed 

 improvement plans. A measurement of some phenomenon during a plan test, 

 when compared to a similar measurement m.ade during the base test, will 

 provide a direct measure of the effects of the plan on the phenomenon 

 in question. Since it is usually desirable that improvement plans be 

 tested for more than one basic condition, base tests are made for all of 

 the conditions for which improvement plans will subsequently be tested. 

 During the course of the Narragansett Bay model study, several astronom- 

 ical tide and several hurricane tide base tests were made. The condi- 

 tions established for these various base tests are described in the sub- 

 sequent paragraphs. 

 Astronomical tide base tests 



35- Two astronomical tide base tests were used for evaluation of 

 the model test data. The first involved reproduction of a normal spring 

 tide, which had a range of k.l ft at Nei'/port, a high-water elevation of 

 +^.1 ft mlw, and a low -water elevation of 0.0 ft mlw. All hurricane 

 tide tests reported herein were made in conjunction with this astronom- 

 ical tide, and supplemental current velocity data and astronomical tide 

 data for all plans reported were obtained for conditions of this tide. 

 In addition, certain current velocity data and astronomical tide data 

 for plans 35 and 36 were obtained for conditions of a mean tide having 

 a range of 3-6 ft at Newport, a high -water elevation of +3-7 f't mlw, and 

 a low-water elevation of +0.1 ft mlw. Test data presented in subsequent 

 parts of this report for plans 35 and 36 show which of the above-described 

 astronomical tides was being used during the test in question. 



36. Base test data for astronomical tides and tidal currents are 

 not shown independently in the remainder of this report; instead, these 

 data are included in data tabulations for direct comparison with similar 



