I KHOA HOC~ ••^•knci.ncisi: V MOT SO KET QUA NGHIEN ClTU R i i RO VE NGUOl DO NGAP"LUT LUtJ VU^C SONG KIEN GIANG VA SONG LONG DAI TINH QUANG BINH Trinmg Van Bon, Vu Van Ngoc, I*ham Thi Han, Vu Phu-ong Quynh, Phong Thi Nghiem Trong Diim Qudc Gia Vi Doni^ Lice Hgc Song Bien- Vien KHTL VN Nguyen Minh Hien Truong Dgi hgc flue Tom tat: Nghien ciru rui ro nggp lut lgi vidng cua song vii ven ba dirge quan (dm tgi nhieu nuac tren thi giai Tgi Viet Nam, vdn di nghien cuu vi rui ro ngdp hil chi mai hdl ddu nhung ndm gdn day, qud khie cong ldc qudn ly nggp lut bao gom bien phdp cong trinh va phi cong trinh rdt dugc chu irong Hien viec xdy dung bdn nggp lui duac the hiin qua viic xdy dirng bdn dd rui ro nggp lut Trong khuon khd bdi bdo h-inh bdy mot so kit qud viec xdy dung bdn rm ro ve nguoi cho luv vuc song Kien Giang vd song Long Dai - tinh Oudng Binh Tii- khda: Rui ro,Nggp lut, Ltm virc, Kien Giang, Long Dgi Summary: Research flood risk in estuaries and eoastal areas were interested in many countries around the world In Viet Nam.research problem about flood nskjusi slarled in recent years, in the past, flood management includes structural measures and non- structural are being focused Currently, the flood mapping was reflecting through risk mapping In the flamework of the article, some results research about the risk assessment in risk mapping due lo flooding in the Long Dai and Kien Gian riverine catchments, Quang Binh province /.s presented Key words: Risks, Flooding, cachments, Kien Giang, Long Dai \ D^T VAN DE The gioi hien dang phai ducmg dau v6i cac tham hga mot gia tang thien nhien dem lai, d5c biet la bao, lu voi cudng dp va tSn suat cang 16n [9] Nhfing t^c dong va hau qu^ mang lai rat lon, dac biet doi voi nuac ta thuang xuyen chiu anh huong ciia thien tai nhu bao, lu Theo uac tinh, a nuac ta hang nam bao, lii da gay thi?t hai khoang 1,5% GDP bao, lu va cuap di sinh mang cua nhleu nguoi [2] Mien Trung la khu vuc hang nam thuong phai Nguai phan bi?n: PGS.TS Nguyin Ngoc Quynh Ngay nh^n bai: 08/6/2015 Ngay thong qua phan bi?n:l 1/8/2015 Ngay duy^t dang: 28/9/2015 CO khoang - tran lu xuat hien tren cac song; thai gian truyen lu rat nhanh, ngap lut xay CO mua Icm chi sau tu - gia; thoi gian tri ngap lut ngan; cuong suat lu rat lon, thay doi theo timg doan song va timg tran lu; bien do, dp sau ngap lut cao, trung binh tir 3m Trong mot so tran lu dac biet lan bien lu CO ths len den 4-5m; thai gian lu len rat ngan tir - ([6], [7]) gay ngap lut nghiem trpng a viing luu Viing duyen hai mien Trung la mgt nhfing noi chiu anh huang nhieu nhat tir thien tai Thuc tien cho thay day la khu vuc dang chju anh huang nhieu nhdt ciia cac loai hinh thien tai, hiem hoa bao gom: bao lu, ngap lut va nuoc dang Theo kh qua diSu tra, thu thap tinh hinh lu bao va thiet hai ciia cac Tinh ven bien Miin Trung nam gan day nhu bang TAP CHl KHOA HpC VA C O N G N G H E T H O Y 10\ S6 28 - 2015 I KHOA HOC j^EIMIBiI^B Bang 1: So lieu thiet hai ve ngiroi va tai san cac tinh ven bien Mien Trung nam (2007-2011) Tinh hinh thien tai TT Tinh Corn bao ATND 10 Ha Tinh Quang Binh Quang Tri Thua Thien - Hue Da Nang Quang Nam Quang Ngai Binh Dinh Khanh Hoa Binh Thuan 10 14 13 10 24 41 47 24 38 Lu 16 21 27 09 28 19 15 15 Tinh hinh thiet hai Ve tai san Ve ngiroi (Trifu Chet Bi thu-ong VNB) 7388,75 240 81 354 4419,76 93 3715,40 168 41 508,90 64 250 747,00 174 121 1275 7806,00 155 621 6116,13 194 1615,26 187 59 17 998,50 57 16 13 263,91 Ghi chu nuoc ta nhung nam gan day viec nghien cuu tinh toan va xay dimg cac ban ngap lut da dugc quan tam cac muc dp chi tiet khac ([8] , [10]) Vi d\i viec tinh toan va xay dung cac ban rui ro ngap liJt cho khu vuc ven bi^n tinh Thira Thien Hue voi ty le 1/250.000 da thuc hien theo npi dung de tai cip tuih ([11]) Cac kkt qua tren deu quan tam d§n viec canh bao nhiing khu vuc co nguy ca ngap sau a cdc miic khac nhau, van toe dong chay v.v Tuy nhien ty le ban nho va nguon so lieu phuc vu tinh toan nhieu han chS, v$y cac k^t qui nhieu han che viec ung dimg thuc t l Trong bai bao se giai thi?u mpt s6 kk qua tinh toan xay d\mg ban d6 rui ve nguai ngap lut vung ven bi§n cura song Nhat Le, tinh Quang Bmh n CO s d KHOA HQC VA PHU'ONG PHAP TINH TOAN RUI RO DO NGAP LVT II.1 Cc S€f khoa hpc cac t6 chuc khoa hgc quoc te cong nhan va hien dang duac cac quoc gia ap dung rpng rai nhusau[l]: Theo cac bao cao nghien CIJU ve giai phap giam thi^u riii ro phong tranh lii lut va thien tai cua cac nudc tien tien nhu Due, Ha Lan, Nhat, Anh Quoc va My, dinh nghia t6ng quat nhat ve nii ro lu lut va thien tai dugc - Loai lii lut: du doan dugc hoac khong the doan truac; Rui ro = (Xac sUat xay ng^p liit) x (Hau qua cua ngap lut) (1) Xac suit xay ngap lut phu thu6c vao nhieu ylu t6 nhu: Do b^n cong trinh d6, ke; cao trinh de, ke; dat sfi dung; xac su|t xuat hien lii, bao, v.v Trong pham vi bai tyao x ^ suat xay ngap lut dugc tinh theo tan suat lu xuat hien Cu the cac truang hpp lu vai tan suat Ql%, Q2%, Q5%, Q10% va Q20% tai thugng nguon dugc xem xet tinh toan (Bang 2) Hau qua cua ngap lut c6 th^ la nguai, tai san Trong bai chi dh cap den thiet hai ve nguai Xac suit ca nhan nao bi chet tai viing ven biln duoc bao ve xay ngSp lut Pd/f.fiood phu thugc vao cac yeu to sau: ^ - Thai gian canh bao truac lu lut xay ra; - Nai tni an CO the / mfic dg tiep xuc voi lu M ; TAP CHl KHOA HOC VA C O N G N G H E - m O v LOI S