永豐水(shui)庫樞紐(niu)座落在慈利縣(xian)許家坊鄉新界村(cun)境(jing)內(nei),壩(ba)(ba)址下距慈利縣(xian)城75 km。水(shui)庫控制(zhi)集雨面積0.71km2,壩(ba)(ba)址上(shang)游(you)干流(liu)長度1.79km,干流(liu)平均坡降63.68‰,大(da)(da)壩(ba)(ba)為心墻土壩(ba)(ba),水(shui)庫正常蓄(xu)水(shui)位(wei)(wei)365.60m,相應正常庫容174萬m3,設(she)計洪(hong)水(shui)位(wei)(wei)366.31m,相應庫容191萬m3,校(xiao)核(he)洪(hong)水(shui)位(wei)(wei)366.65m,死水(shui)位(wei)(wei)345.5m,相應死庫容5萬m3。樞紐(niu)工(gong)程(cheng)主要(yao)由大(da)(da)壩(ba)(ba)、溢洪(hong)道和輸水(shui)設(she)施等(deng)永久性(xing)建(jian)筑物(wu)組成。工(gong)程(cheng)于1959年(nian)2月(yue)動(dong)工(gong)興建(jian),1975年(nian)10月(yue)竣工(gong)。最大(da)(da)壩(ba)(ba)高28.59m,壩(ba)(ba)頂(ding)高程(cheng)367m,頂(ding)寬(kuan)4m,壩(ba)(ba)頂(ding)軸長84m,總庫容191萬m3,是一座以灌溉為主、兼顧(gu)防(fang)洪(hong)、供(gong)水(shui)綜合利用的(de)小(一)型水(shui)庫。根據(ju)《水(shui)利水(shui)電工(gong)程(cheng)等(deng)級劃分及洪(hong)水(shui)標準》(SL252-2000),該(gai)水(shui)庫工(gong)程(cheng)等(deng)別為Ⅳ等(deng),主要(yao)建(jian)筑物(wu)級別為4級,次(ci)要(yao)建(jian)筑物(wu)級別為5級。