Boundary Channel
... that Boundary Channel off the Potomac River in Washington, D.C. was dredged and widened to provide fill material to raise the ground by more than 8 feet (2.4 m) when The Pentagon was constructed?
... that <b id="mwA4M"><a href="./Boundary_Channel" id="mwA4Q" rel="mw:WikiLink" title="Boundary Channel">Boundary Channel</a></b> off the <a href="./Potomac_River" id="mwA4U" rel="mw:WikiLink" title="Potomac River">Potomac River</a> in <a href="./Washington,_D.C." id="mwA4Y" rel="mw:WikiLink" title="Washington, D.C.">Washington, D.C.</a> was dredged and widened to provide fill material to raise the ground by more than <span about="#mwt20" data-mw='{"parts":[{"template":{"target":{"wt":"convert","href":"./Template:Convert"},"params":{"1":{"wt":"8"},"2":{"wt":"ft"}},"i":0}}]}' id="mwA4c" typeof="mw:Transclusion">8 feet (2.4</span><span about="#mwt20" typeof="mw:Entity"> </span><span about="#mwt20">m)</span> when <a href="./The_Pentagon" id="mwA4g" rel="mw:WikiLink" title="The Pentagon">The Pentagon</a> was constructed?