Drought and water usage issues Lake Mead

lake mead seen hoover dam white band showing high water level

in june 2010, lake @ 39% of capacity, , on november 30, 2010, reached 1,081.94 ft (329.78 m), setting new record monthly low. mid-may 2011 january 22, 2012, lake mead s water elevation increased 1,095.5 1,134.52 feet (333.91 345.80 m) after heavy snowmelt in rocky mountains prompted release of 3.3 million acre feet (4.1 km) glen canyon lake mead.

in 2012 , 2013, colorado river basin experienced worst consecutive water years on record, prompting low glen canyon release in 2014 – lowest since 1963, during initial filling of lake powell – in interest of recovering level of upstream reservoir, had fallen less 40% capacity result of drought. consequently, lake mead has fallen significantly, reaching new record low in 2014, 2015 , 2016. in 2014, record low 1,081.82 feet (329.74 m) on july 10, 2014. on june 23, 2015, lake mead reached new record low when briefly fell below 1,075.0 feet (327.7 m), first official drought trigger elevation, first time since lake filled. if lake below elevation @ beginning of water year (october 1), official shortage declaration bureau of reclamation enforce water rationing in arizona , nevada.

lake mead s water level rebounded few feet october 2015 , avoided triggering drought restrictions. however, water level starting falling in spring 2016 , fell below drought trigger level of 1,075 feet again in may 2016. fell new record low of 1,071.61 feet (326.63 m) on july 1, 2016 before beginning rebound slowly. drought restrictions narrowly avoided again when lake level rose above 1,075 feet on september 28, 2016, 3 days before deadline. reprieve steady annual decline occurred in 2017 when lake levels rose throughout year due heavier normal snowfall in rocky mountains. result of large snowmelt, lake regained water levels had in 2015 seasonal high of 1,089.77 feet (332.16 m). seasonal low of 1,078.96 feet (328.87 m) in 2017 close experienced in 2014, safely above drought trigger now. however, level still 36 feet below seasonal low experienced in 2012 , lake projected begin falling again in 2018.

as result of decreasing water level, marinas , boat launch ramps have either had relocated area of lake or have closed down permanently. las vegas bay marina relocated in 2002 , lake mead marina relocated in 2008 hemenway harbor. overton marina , echo bay marina have been closed due low levels in northern part of overton arm. government wash, las vegas bay, , pearce ferry boat launch ramps have been closed. las vegas boat harbor , lake mead marina in hemenway harbor/horsepower cove remain open, along callville bay marina, temple bar marina, boulder launch area (former location of lake mead marina) , south cove launch ramp.

changing rainfall patterns, climate variability, high levels of evaporation, reduced snow melt runoff, , current water use patterns putting pressure on water management resources @ lake mead population relying on water, , hoover dam electricity, continues increase. lower minimum lake level necessary generate electricity 1,050 feet (320 m) 950 feet (290 m), hoover dam retrofitted wide-head turbines designed work efficiently less flow in 2015 , 2016. if water levels continue drop, hoover dam cease generating electricity when water level falls below 950 feet , lake stabilize @ level of 895 feet (273 m) when water reaches lowest water outlet of dam. in order ensure city of las vegas continue able draw drinking water lake mead, $1.5 billion spent on building new water intake tunnel in middle of lake @ elevation of 860 feet. 3-mile tunnel took 7 years build under lake , put operation in late 2015.