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The Webhannet River is an 〔U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. (The National Map ), accessed June 30, 2011〕 river whose watershed is contained entirely within the town of Wells, Maine. The river has five tributaries, including three with official names: Pope’s Creek, Depot Brook, and Blacksmith Brook. Draining a sandy outwash plain left by the last glacier, they run parallel to the southern Maine coastline behind the heavily developed barrier beaches of Wells and Drakes Island. The river flows into Wells Harbor, then empties between a pair of jetties into the Gulf of Maine.〔 The Webhannet watershed includes of land under conservation, including of estuary salt marsh and uplands protected by the Rachel Carson National Wildlife Refuge.〔 ==Jetties== In 1961-62, the U.S. Army Corps of Engineers built two rubble-mound jetties to protect the channel to the harbor. The north jetty was long, the south one , and extended roughly from the inner harbor to just past the beaches. A 1-ft-thick bedding layer and core of 3-in. to stone was covered with a double layer of stones weighing a minimum of two tons on the landward section and three tons on the seaward sections, for a total of 20,000 tons of stone. The cost for placing the stone was $95,600.〔 〕 In 1962-63, the north jetty was extended seaward at a cost of $29,300.〔 In 1965, the north and south jetties were extended seaward 1,225 and , respectively. The work required a total of 119,000 tons of stone and cost $594,600 ($ today).〔 The extensions are parallel to one another, spaced apart, and terminate at a depth of eight feet below the low-water mark. Their height above low water ranges from on their seaward ends to (north jetty) and (south jetty) at their landward ends. Their flat crowns are wide at the seaward end and wide at the landward end.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Webhannet River」の詳細全文を読む スポンサード リンク
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