沙(sha)溪(xi)(xi)(xi)是閩江(jiang)(jiang)的主流(liu),發源于(yu)武夷山(shan)脈(mo)杉(shan)嶺南麓(lu)的九縣(xian)(xian)山(shan),屬(shu)建寧(ning)縣(xian)(xian)均口(kou)(kou)鄉;源頭為水茜溪(xi)(xi)(xi),流(liu)經(jing)漁潭至(zhi)寧(ning)化稱(cheng)東溪(xi)(xi)(xi),在(zai)寧(ning)化縣(xian)(xian)城下游匯入(ru)武義溪(xi)(xi)(xi)后稱(cheng)九龍(long)溪(xi)(xi)(xi),向東流(liu)向清(qing)流(liu),寧(ning)化境內(nei)合(he)水口(kou)(kou)以下又(you)稱(cheng)翠江(jiang)(jiang)。清(qing)流(liu)境內(nei)一段(duan)又(you)稱(cheng)龍(long)津河(he)。九龍(long)溪(xi)(xi)(xi)流(liu)至(zhi)永安西郊10公(gong)里處有(you)文川(chuan)溪(xi)(xi)(xi)匯入(ru),兩條溪(xi)(xi)(xi)流(liu)猶(you)如(ru)燕(yan)(yan)尾(wei),合(he)流(liu)過后河(he)段(duan)猶(you)如(ru)燕(yan)(yan)身,永安東郊一段(duan)猶(you)如(ru)燕(yan)(yan)頭,故這段(duan)5公(gong)里溪(xi)(xi)(xi)流(liu)又(you)稱(cheng)燕(yan)(yan)江(jiang)(jiang)。永安至(zhi)沙(sha)溪(xi)(xi)(xi)口(kou)(kou)稱(cheng)沙(sha)溪(xi)(xi)(xi),沙(sha)溪(xi)(xi)(xi)流(liu)經(jing)寧(ning)化、清(qing)流(liu)、明溪(xi)(xi)(xi)、永安、三明、沙(sha)縣(xian)(xian)等六個縣(xian)(xian)市,在(zai)沙(sha)溪(xi)(xi)(xi)口(kou)(kou)與(yu)富(fu)屯溪(xi)(xi)(xi)匯合(he)后注(zhu)入(ru)閩江(jiang)(jiang),此處建有(you)沙(sha)溪(xi)(xi)(xi)口(kou)(kou)水電站。
沙(sha)(sha)溪全(quan)長(chang)328公(gong)(gong)里,集水(shui)(shui)(shui)(shui)(shui)面積11793平(ping)方公(gong)(gong)里,占(zhan)閩江(jiang)流域總面積19.33%,全(quan)年不會發生河(he)干、斷流和(he)冰(bing)封現象(xiang)。降雨期集中(zhong)在4月(yue)至8月(yue),水(shui)(shui)(shui)(shui)(shui)位(wei)(wei)暴(bao)漲(zhang)暴(bao)落,洪峰持續(xu)期短,枯(ku)水(shui)(shui)(shui)(shui)(shui)期長(chang)(9月(yue)至翌年3月(yue))。1955~1984年,沙(sha)(sha)縣石(shi)橋水(shui)(shui)(shui)(shui)(shui)文站(zhan)最(zui)高(gao)水(shui)(shui)(shui)(shui)(shui)位(wei)(wei)為羅星塔零點基(ji)面以上112.95米(mi)(mi),最(zui)低水(shui)(shui)(shui)(shui)(shui)位(wei)(wei)為103.70米(mi)(mi),平(ping)均(jun)水(shui)(shui)(shui)(shui)(shui)位(wei)(wei)為104.58米(mi)(mi)。沙(sha)(sha)溪航道,河(he)床多(duo)是河(he)谷型盆地和(he)河(he)曲型河(he)谷相間,河(he)床質為巖石(shi)和(he)沙(sha)(sha)卵石(shi),河(he)寬寬窄相間,水(shui)(shui)(shui)(shui)(shui)深深淺不一,很多(duo)河(he)段巖盤連片,礁(jiao)石(shi)棋布,險灘(tan)多(duo),水(shui)(shui)(shui)(shui)(shui)流湍急,流態(tai)紊亂(luan),而(er)沙(sha)(sha)卵石(shi)淺灘(tan)多(duo)的(de)(de)河(he)段又長(chang),一般水(shui)(shui)(shui)(shui)(shui)深只有0.3~0.8米(mi)(mi)。沙(sha)(sha)溪通航里程,從(cong)寧化縣的(de)(de)禾口起至南平(ping),全(quan)長(chang)324.4公(gong)(gong)里,1965年寧化縣境內的(de)(de)橫鎖以上修建了水(shui)(shui)(shui)(shui)(shui)利閘壩,使40公(gong)(gong)里河(he)段不能通航,通航里程橫鎖至南平(ping)為276.2公(gong)(gong)里。
沙溪流(liu)域從1993年開始,三(san)明市大力開展(zhan)沙溪河航電(dian)(dian)(dian)(dian)(dian)(dian)綜合開發項目(mu),至(zhi)2004年,共有永安(an)安(an)砂(sha)電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、永安(an)豐海電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、永安(an)鴨姆潭(tan)電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、永安(an)西門(men)電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、永安(an)貢川電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、三(san)元竹洲(zhou)電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、三(san)元臺江電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、梅(mei)列斑竹電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、沙縣城關電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、沙縣高砂(sha)電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)、沙縣官(guan)蟹(xie)電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)11個梯級電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)。沙溪河梯級電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)總(zong)裝機(ji)容量(liang)11處(chu)/46.71萬千瓦,其(qi)中:已建成電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)8處(chu)/37.71萬千瓦,在建電(dian)(dian)(dian)(dian)(dian)(dian)站(zhan)(zhan)(zhan)(zhan)3處(chu)/9萬千瓦。
不亞于(yu)珠江夜景(jing),尤其是三明的部分(fen)。