spring creek dam dam tributary state california completed dam maintained serves primarily collect severe acid drainage stemming dam forms mile long flow reservoir square mile km2 watershed dam directly upstream city california operation primary purpose spring creek dam collect acid drainage old heavily tributaries dam built response primary water supply millions watershed small comparison stream acidic world dam reservoir treatment structures built successfully reduced dry weather pollution ninety percent problems occur mainly form large reservoir concerns structural integrity safety dam physically arose 1990s emergency releases value thousands acre feet water occurred time time massive acid drainage history mining productive copper california point history operated banks tributaries upstream current dam site 1960s extracted iron ore silver gold copper ore rock formation dating approximately years ago potential site discovered men surveyor discovered extensive iron ore deposit tributaries silver discovered site begun ownership transferred london company end 19th century took blames fish kills mining activity continued tons ore extracted site day continuing problem runoff described acid drainage illustrated problems iron mountain california release waste resulted virtual elimination aquatic life creeks surrounding iron mountain site work continuing possibly largest difficult acid drainage problem united_states controlling environmental pollution events prompting construction construction dam regulating downstream dam respectively severely impaired capability flush away acid drainage flowed directly reservoir contaminated sediment turning portion water red shade previously water continued creek river pacific_ocean water extremely difficult removed open pit mining began site peak discharged tons iron pounds copper pounds stream day water flowing drainage contaminated necessitated construction holding dam spring creek dam spring creek dam begun company named reed awarded contract clearing operations began july year dam officially dedicated september construction dam began october placing dam embankment partially consists acidic sediment laid upstream face dam beginning november year series labor strikes impacted communities affecting construction dam temporarily halted year work restarted june core material dam soon supply material complete dam core eventually closed pollution continued continues listed known having acidic naturally found water content earth samples having value tested early 1990s roughly times battery acid value found inside near average water entering spring creek reservoir storage expansion spring creek dam later deemed spring creek watershed large flows natural drainage acid drainage caused frequent dam contain volatile components acid drainage include acidic naturally occurring laboratory water earth alternatives considered problem spring creek dam create reservoir times original size plan considered built cost estimated million partial covering site ore body determined shallow alternative considered recurring high occurrence mountain inefficient implemented construction dams upstream proposal called dams upstream reduce watershed percent including dam branch plan implemented removing need dam waste rock removal rock extracted removed piles disposed cell tributary level lowered slightly recent history found water foundations spring creek dam possibly cause collapse shortly discovery controversy irregular dam began 1990s years later march unexpected spill acidic water rushed dam spill heavily contaminated reservoir threatened water supply california despite fact region suffering drought acre feet water released half pollution loss water badly needed agricultural users estimated million water treatment plant built site named minnesota flats near lime balance acid drainage water diverted treatment site altogether percent water removed treatment process roughly miles specialized acid resistant pipeline cost million mile included treatment process water flowing directly level close mentioned earlier found small amounts water natural flow tributaries water diverted nearby acidic water requires treatment southeast flowing mile long tributary receiving water approximately square miles km2 land creek begins drainage flows generally south east direction turning south sharply west spring creek reservoir reservoir continues west directly arm reservoir creek actually runs acid drainage found creek actually carried smaller tributaries stream runs southeast north spring creek stream drains south flows southeast small tributary flows west north spring creek reservoir basin lies far receives acid drainage outflow reservoir highly erratic ranging cubic feet second roughly cubic feet second particular day period march april small southeast flowing stream rises sacramento river upstream stream receives contaminated runoff nearly acidic spring creek stream rises flows east meet downstream dimensions operations spring creek dam feet high feet long crest feet thick base crest stands feet sea level reservoir feet sea level pool crest level pool reservoir holds acre feet water depth roughly feet runs crest dam left bank canyon feet wide able accommodate water flow cubic feet second outlet works dam located base accommodate water flow cubic feet second spring creek powerplant downstream dam generates kilowatts spring creek powerplant spring creek powerplant located base spring creek dam actually supplied flow lake formed drainage downstream streams run east river power plant completed began operations capacity capacity later upgraded plant peaking power plant separate generators generating power operations distributing excess power local power grid water diverted roughly miles long feet diameter gives detailed report specifications generating plant powerplant houses generators rated power factor francis turbines conveys water located spring creek powerplant power varies diameter metres metres length power consists tunnels twin tunnel leading powerplant trinity river division central valley project spring creek reservoir artificial lake formed dam reservoir flood control storage rarely filled acre feet capacity dry season water pools small pond retained dam contaminated sediment acidic waste reservoir space flows dam upstream sufficient flush contaminated water away water held reservoir released outlet works reservoir despite operation strategy reservoir eventually deemed inadequate watershed filled capacity single heavy storm event frequently poured floods crest dam lacks gates result numerous fish kills occurred sudden releases major consistent acid pollution reservoir large fish spawn downstream red bluff diversion dam dam near california outlet works spring creek dam able release cubic feet water second crest outlet works begins left bank dam elevation feet drops roughly feet vertical distance face dam basin flowing roughly feet wide carry cubic feet second outlet works tunnel dam elevation lower terminates exit design commonly seen storm drains rarely seen dams base dam maximum capacity outlet works cubic feet second
Spring Creek Dam