ThiJtc tieh - Kinh nghiem
Bao Ion va suf dung hen virng
NGUON TAI NGUYEN N U ( 5 C
Nuac ta CO khodng 2.360 con song CO chieu ddi hon 10km. Trong sd 13 hai vuc song chinh vd nhdnh CO dien tich ldn han lO.OOOknr- thi de'n 10113 song co quan he vdi nudc ldng gieng, trong do 3113 song thugng nguon a Viet Nam, hg nguon chdy sang nuac ldng gieng, 7 song thugng nguon a nuac ldng gieng, hg nguon a Viet Nam. Dieu ndy cho thdy Viet Nam khong nhimg bi rdng bugc nguon lgi ve nudc vdi cdc qudc gia chia se, md cdn bi dgng trU&c sU cgn kiet tdi nguyen nUdc (TNN) co xu hudng ngdy mgt tdng.
O TS. TRAN THANH LAM
Vien Tdi nguyen nudc vd Moi trudng Dong Nam A
Tinh hinh khai thae va sir dung nudc
Viet Nam la nude Ddng Nam A cd chi phf nhilu nhit cho thuy lgi. Ca nudc hien cd 75 he thd'ng thuy ndng, vdi 659 hd, dap ldn vl vQa, tren 3.500 hd, dap nhd, 1.000 cdng tieu, tren 2.000 tram bom ldn nhd, tren 10.000 miy bam d c loai, cd k h i nang cung d p 60 - 70 ty mVnam. Tuy nhien, nhilu he thd'ng thuy ndng da xud'ng d p nghiem trgng, chi dip Qng dugc 50 - 60%
cdng suit thiei ke. Lugng nudc su
dung hang nam cho ndng nghiep khoing 93 ty m \ cdng nghiep: 17,3 ty m \ dich vu: 2 ty m', sinh boat:
3,09 ty m'.
Hien nude ta cd tren 240 nha m i y d p nudc dd thi vdi tdng cdng suit thiet ke'la 3,42 trieu mVngly.
Trong dd, 92 n h l miy su dung ngudn nudc mat vdi tdng cdng suit 1,95 trieu mVngay va 148 nha m i y sQ dung ngudn nudc dudi dit vdi tdng cdng suit khoing 1,47 trieu mV ngly. Nhilu dja phuong su dung ca 2 ngudn nude mat va
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Tdi nguyen vd Mdi trudng | Ky 1 • Thang 3/2011 3 3
nudc dudi dat. Tdng cdng suit hien cd cua cac nha may d p nudc bao dam cho mdi ngudi dan dd thi khoang 150 1ft nudc sach mdi ngay. Tuy nhien, do co sd ha tang, he thd'ng d p nudc tai nhilu khu dd thi lac hau, thieu ddng bd nen he thdng d p nudc khu dd thi chua phat huy hei cdng suit, ti le thai thoat nudc sach k h i cao (cd nai ti le thai thoat tdi 40%). Chfnh vi vay tren thuc te, nhilu dd thi cung d p nudc chi dat khoing 40-50 Ift/ngudi/ngly.
Khu vuc ndng thdn nudc ta cd khoang 36,7 trieu ngudi dan dugc d p nudc sach (tren tdng sd 60,44 trieu ngudi). Cd 7.257 cdng trinh d p nudc tap trung d p nudc sinh boat cho 6,13 trieu ngudi va tren 2,6 trieu cdng trinh d p nudc nhd le khac. Cd tren 50% hd dan dang dung nude gieng khai, 25% dung nudc sdng sudi, tren 10% dung nudc mua.
Nguyen nhan suy giam nguon tai nguyen nudc
Mdt Id, do tdc ddng cua bien ddi khi hgu todn cdu
Nhiet dp khong khi: cd xu the ngay mdt tang Ien da dugc khang dinh. Kich ban cd the chap nhan la de'n nam 2070, d cle \aing ven biin cd kha nang tang them -i-l,5"C, vung ndi dia +2,0"C, chung keo theo lugng bde tholt hai tang khoang 7,7- 8,4%, nhu clu tudi tang Ien, lugng ddng chay nudc mat se giam di tucmg Qng khi lugng mua khdng ddi.
Bdo hit: ElNino va LaNina (ggi tit ENSO) lam tang them tfnh cue doan cua thdi tiei. Hau qui lam tang them tfnh cue doan cua lugng ddng chay trong nam tren cac ddng sdng, nhit la LaNina
thudng mua ldn, nudc sdng dang cao gay lu lut nhilu nai. Diln hinh nhu nhung tran Ifl cudi nam 2010 d d c tinh miln Trung, lu chdng len lu.
Hgn hdn: ElNino gin liln vdi viec gay ban ban rit nang nl d nudc ta. Nhirng nam cd ElNino, lugng mua va lugng ddng chiy trong sdng dac biet la trong mua can thudng bi gilm manh, tham chi khdng cd ddng chiy nhu sdng Ldng (Binh Thuan), sdng KrongBuk (Die Lie)... Han khie'n cho gia sue va hang chuc ngan hecta cay trdng bi chei do thieu nudc.
Muc nuac bien ddng: Muc nudc biin dang len keo theo su xam nhap man vio sau trong dat liln cd nam lln sau tdi 50km, lam giam ding ke TNN nggt...
Hai la, khai thdc vd su dung TNN thieu ben vdng
Bit cQa cle phan luu d l khai thic d c bai sdng trong de sQ dung cho muc dfch ndng nghiep. Diln hinh nhu: Nam 1900, bit cQa sdng Ca Ld la phan luu tu nhien cua sdng Hdng, sdng Ca Ld trd thanh mdt nhanh cua sdng Clu, sdng chQa nudc mua, nudc thai d nhiSm cae chit bun ca, diu md.
Nam 1937, bit sdng Day bing dap Day, sdng Day trd thinh khuc sdng chet (tQ dap Day de'n Ba Thi). Nam 1967, bit cQa D l y bing cdng Van Cdc va De Cua Hat d l khai thic bung hd Van Cdc - dap Day.
CIc sdng nhd, kenh rach trong ngi dd cac thinh phd bi d nhiim nang do nudc thli sinh boat, cdng nghiep nhu: CIc sdng Td Lich, sdng Set, Kim Ngun... chiy trong ndi thanh Ha Ndi bi d nhiim rit nghiem trgng true tie'p dd vao sdng
Nhue. Cac kenh Nhieu Ldc - Thi Nghe, kenh Tau Hu, kenh Tan Hoa - Ld Gdm, kenh Tham Luang, kenh Ddi - Te va d c kenh rach khic chay trong ndi dd TP. Hd Chf Minh dd true tie'p vio sdng Sai Gdn gay d nhifim nghiem trgng.
CIc sdng ndi chung cd thi bi phan doan d nhiim khi sdng chay qua cac khu dd thi, khu cdng nghiep, lang nghl hay boat ddng ndng nghiep. Diln hinh nhu doan sdng Clu chay qua khu edng nghiep gang thep v l TP. Thai Nguyen.
Xay dung dap dang sQ dung hei lucmg nudc ca bin tao ra khuc sdng "khd" dudi dap, dd la mdt sd dap dang thuy lgi nhu dap Thach Nham tren sdng Tra Khuc, dap Lai Giang tren sdng Dai Giang,... 30 nam trudc day vl mua khd vln cd nudc trin qua dap. Vai chuc nam gin day do tang dien tfch tudi, tang lugng nudc d p cho sinh boat, cdng nghiep, mat khic do rQng diu ngudn bi tan pha nang n l nen mua khd d ha luu hei nude, cd nam keo dii vii ba thang, neu khdng cd mua, d e vung ha lun d c dap dang nay nhilu cu dan sinh sd'ng ven sdng va tren sdng, chiu tac ddng tieu cue rat dang ke. Cac dap dang thuy dien thudng tao ra khuc sdng "chei" doan giQa ha luu dap va nha may va do dieu tiei ngay dem tao ra nQa ngay d ha luu khdng cd nudc xa.
Trong qui hoach, thiet ke cac hd chQa nude, mdt thdi gian dai khdng quan tam den hoac quan tam khdng day du de'n ddng chay mdi trudng phfa ha lun dap.
Khai tbac nudc qua mQc thie'u qui hoach, ke hoach ddng bd, nhu: Khai tbac nudc ngam qua mQc gay d nhiim trim trgng d Die 3 4 Tdi nguyen vd Mdi trudng | Ky 1 - Thang 3/2011
Lie, Ninh Thuan va Binh Thuan, ddi hdi phai cd bien phap bd cap.
Cung nhu theo qui hoach vl ngudn nudc, de'n nam 2010 dap Qng yeu d u d p nude tudi cho 5 tinh Tay Nguyen la 80.000 ha c l phe. De'n nam 2000 rieng tinh Die Lie da trdng dugc 260.000 ha c l phe. Hau qui 11 khdng du nudc tudi, nen hing chuc ngan ha ca phe bi chei.
Quan ly TNN bi phan tin, tfnh rang budc khdng chat che, thie'u thd'ng nha't nen da xly ra tinh trang: Thilu nudc "nhan tao" do khdng cd qui trinh van hanh hd vl mua can (nudc sdng Hdng khdng dap Qng yeu d u muc nude cin thiet trong d c thing II, III hang nam).
Giai phap bao ton va sir dung ben vufng nguon tai nguyen nudc
Hgn che vd gidm thieu suy thodi TNN: Cli thien, nang d p va md rdng cle he thdng tholt Ifl, tieu ung. Thuc hien nghiem chinh cac Luat TNN, Luat Bao ve mdi trudng, De diiu... bao dam tholt lu, bao ve bd sdng, chinh tri long sdng, cua sdng thdng thoat lu. Nang d p de biin, de cQa sdng, ciing cd bdi true de sdng dam bao an toln de vdi muc nude thiei ke da qui dinh.
Khai thae hgp ly dat dai chua su dung. Thuc hien ca che san xua't saeh. Trdng vl bio ve riing dau ngudn vl rimg phdng hd, dac biet la rimg ngap man ven biin.
Hgn che'vd gidm thieu suy thodi TNN do khai thdc, sddung TNN
V enong nghiep: Giam nhu clu nudc, tudi tiet kiem nudc, giam tdn thai nudc bao gdm: CQng hoa kenh muong; nang d p cdng trinh diu md'i; nang cao hieu qua quan ly;
chuyin ddi ca d u cay trdng, vat nudi cd nhu d u sQ dung nudc thip, nhung cd gia tri kinh te cao; phdng chd'ng d nhiim ngudn nudc.
Ve cong nghiep: Nang cao hieu q u i tai sQ dung nude; xay dung he thd'ng xQ ly nudc thai;
phdng chd'ng d nhiim ngudn nudc.
Ve khai thdc sic dung nguon nudc di doi vdi bdo ve nguon nudc: Bao dam duy tri ddng chay mdi trudng cho d c ddng sdng khoe manh, bao ve va phit triln he sinh thai thuy sinh; dam bao ddng chay mdi trudng theo qui hoach, thie't ke van hanh elc hd chQa nudc thuy lgi, thuy dien va dap dang; cd ke hoach bien phap bd cap nudc ngam nhung vung khai tbac q u i mQc, phdng chd'ng hoang mac hoi.
Ve ddu tu nghien cicu kiem ke ddnh gid vd qui hogch du bdo ddi hgn TNN: Du bao theo mua, nam va nhilu nam vl ngudn nudc, thien tai, lu lut, ban ban di kem vdi hien tugng ENSO... de cd ke hoach sQ dung hgp ly vl an toan ngudn nudc.
Ve qudn I'y tong hop TNN: To chQc elc luu vyc sdng cd ca che quan ly thfch hop, hieu qua theo Nghi dinh 120/2008/ND-CP v l quan ly luu vuc sdng; cung cd va xay dung md'i quan he hgp tac vdi cac nudc ling giing vl quin ly TNN ddi vdi cac sdng xuyen bien gidi.
Hgn che vd gidm thieu suy thodi TNN do Ludt phdp, qudn ly vd to chiec: Sdm ban hanh dly du, ddng bd nhflng van ban dudi Luat hudng din thi hinh Luat Bao ve mdi trudng va cac Luat cd lien quan den TNN; tap trung thd'ng nha't ca quan quan ly TNN thdng sud't tQ
trung ucmg de'n dia phucmg va sdm thanh lap cac td chuc quan Iy luu vuc sdng thfch hgp vdi nhiem vu chQc nang rd ring, boat ddng cd hieu qua; cd co che, chfnh sach d l ngudi dan, d c td chQc cdng ddng tham gia thuc sir bao ve TNN, bio ve mdi trudng nude, tao diiu kien cho ngudi dan tham gia ngay tQ khi lap quy hoach xay dung de'n khai thic, sQ dung vl bio ve.
Tie'p can vd trien khai hgch todn tdi nguyen moi trudng vdo cong tdc bdo ton vd phdt trien TNN ben vioig
Hien nay, d nude ta, phuomg phap nay vln chua dugc Ip dung do chua cd luat phip quy dinh thi hinh. TNN dang dugc con ngudi sQ dung cho nhilu muc dfch nhu thuy dien, thuy Igi, nudc d p cho sinh boat va cdng nghiep, du Iich, nudi trdng thuy san..., nhung khdng mdt ai phai tra ba't ky chi phf nao cho quyin khai tbac, sQ dung (trQ chi phf giao dich va chi phf hinh chfnh cho viec xin giiy phep su dung trong mdt vai trudng hgp). K l ca khi cd nhung thiet hai xly ra do viec suy thoai TNN, nhu thie'u nudc vio mua khd, d nhiim ngudn nude tren dien rdng... vln khdng h i cd chi phf nao dugc tfnh cho viec viec su dung nudc. Da sd cac chQc nang dich vu cua mdi trudng nude nhu khi nang duy tri he sinh thai tu nhien, kha nang hap thu vl hda gili cac chat d nhiim, diiu hda khf hau, tao canh quan... diu khdng cd gia tren thi trudng. Cd the ndi, nudc la mdt trong nhflng loai tai nguyen tu do tie'p can, khie'n cho nd bi khai thae va sQ dung qua mQc, trong khi diu ra ludn ludn cd chQa yeu td d nhiim mdi trudng. TNN cua nudc ta dang bi suy thoai do bie'n ddi khf hau va khai tbac trin lan, thieu ke
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Tdi nguyen vd Mdi trudng | Ky 1 - Thang 3/2011 3 5
