(2) The barrier would be of rock-fill construction. 

 It would be trapezoidal in shape with a 20-foot top width at 

 elevation 22.0 feet above mean sea level and with side slopes 

 of 1 vertical on 2 horizontal on both the ocean and bay sides. 

 The cap stones would consist of derrick stone of 20 ton rainimum 

 size. The cap stones would extend across the top and down both 

 sides to an elevation 20.0 feet below mean sea level. 



(3) An ungated navigation opening, UOO feet wLde by kO 

 feet deep at mean low water, would be provided. 



(U) The highway across Round Swamp on Conanicut Island 

 would be raised to 22 feet above mean sea Isvel and protected by 

 a stone facing. 



below: 



(5) The pertinent data for the West barrier are summarized 



b. 



of -way, land for relocation and maintenance areas, and shore-frsnt 

 easements. The construction of the barrier, at the site selected, 

 would require no relocation of highways or utilities. However, 

 modification of the existing highway across Conanicut Island would 

 have to be made in order to meet the required land wall which 

 follows the existing road alignment. The cost of lands and 

 damages has been estimated upon the basis of current market values, 

 field reconnaissance and information secured from local authorities. 



F-18. TIVERTON BARRIER 



a. Description and pertinent data , 



(l) The Tiverton barrier and related dike system would 

 extend along the south shore of the Island Park section of Ports- 

 mouth, thence across the Portsmouth-Tiverton Channel and continue 

 in a southerly direction along the Tiverton shore. 



F-m 



