CÁC GIẢI PHÁP QUẢN LÝ TÀNG CHỨA NƯỚC VEN BIỂN BÌNH THUẬN TRONG BỐI CẢNH BIẾN ĐỔI KHÍ HẬU

Tieu ban: Cdc Khoa hoc vi Trdi ddt

ISBN: 978-604-913-016-

CAC GIAI PHAP QUAN LY T A N G CHITA NU^OC VEN BIEN BINH
T H U A N T R O N G BOI C A N H BIEN DOI KHI H A U
•

•

SOLUTIONS FOR MANAGING OF COASTAL AQUIFERS IN BINH
THUAN PROVINCE IN CONTEXT OF CLIMATE CHANGE
Phan Thi Kim Van', Nguyen Thi Kim Thoa', Giuseppe Arduino ,
Paolo Bono\ Nguyen Van Giang", Biii Tran Vu•g^lg^ Peter Dillon'',
Tran Viet Hoan^ Nguyin Thi Nhan^
^'' Vien Dja Chit, Ngd 84, phi Chiia Ling, Ddng Da. H i Ndi, E-mail:
,
'2' Vien Vit Ly Dja Ciu, *^' Hydrological/Geologieal Unit. UNESCO Office,
Jakarta, Indonesia. '"^'Tlng hgp "La Sapienza". Rome. Italy, '"'Trung tim Dieu tra vi Quy
hoach TNN, *^' CSIRO Land & Water, SA, Australia, '^' Vien Dja Chit v i Dja vit ly Biin
Tom tat:

Bdi bdo trinh bdy kit qua nhdn dugc tir cdc nghien cuu cua hai de tdi "Bd
sung nhdn tgo nuac dudi ddt a tinh Binh Thudn (2004-2007), Thich nghi vai bien
doi khi hdu: Qudn ly cdc Idng chira nude ven bien mien Trung Viet Nam (20082010).
Muc tieu cua cdc de tdi ndy la: a) Xdy dung mdt du dn thi diem vimg ddi cdt
tinh Binh Thudn nhu la thu nghiem cdng nghe bd sung nhdn tgo nuac dirai ddt a
Ddng Nam A, b) Ddnh gid cdc gidi phdp vd hiiu qud qudn ly mrac dudi ddt thdng
qua cdc cdng nghe bd sung nhdn tgo nuac dirai ddt, c)Chuyen giao kiin thirc vd
kinh nghiem tdng cirang ngudn nude bdng cdng nghe bd sung nhdn tgo, d) Cung
cdp nude sgch cho cdng ddng viing bj hem Idu ddi, e)Lira chgn cdc giai phdp quan

ly tdng chira nuac de cung cdp nuac sgch vimg ven bien trong bdi canh bien ddi
khi hdu.
Vung nghien ciru la mdt trong nhirng vimg khd hgn nhdt ciia Viet Nam, thudc
khu vuc ven bien cua tinh Binh Thudn, cdch thdnh phd Hd Chi Minh 200 km ve
phia Ddng Bdc.
Abstract
This paper presents the results obtained from two the projects: "Groundwater
Artificial Recharge in Binh Thuan Province, Viet Nam" (2004-2007) and
"Adapting to Climate change: Managed Aquifer recharge at coastal zone in
Central Part of Vietnam " (2008-2010).
The objectives of these projects are: a) lo build up an experimental pilot
project in the sand dune area of Binh Thuan Province, as an example of artificial
recharge in Southeast Asia, b) to assess methodologies and effectiveness of
groundwater management through groundwater recharge technologies, c) to
transfer knowledge and experience of augmenting groundwater resources by
artificial recharge lo scientists, d) to supply good quality water to the
communities periodically affected by longstanding droughts, e) to chose solutions
of Management of Aquifer Recharge for Mater's supply in context of climate
change in Vietnam.
The study area is one of the driest part of Vietnam, located in the Binh Thuan
Province along the coastal plain in the lower part of Central Eastern Viet Nam.
172


Hgi nghi Khoa hgc kv niem 35 ndm Vien KIwa hgc vd Cong nghe Viet .Nam - Hd Ngi JO 20JO

GIOI THIEU
Bii bio trinh biy kit qui nhin duge tir eic nghien cim cua hai de tii "Bd sung nhin
tao nude dudi dit d tinh Binh Thuan (2004-2007), Thich nghi vdi biin ddi khi hiu: Quin ly
eic ting chira nude ven biin miln Trung Viet Nam (2008-2010).

Mue tieu ciia eic de in niy li: Xiy dung mdt de in thi diem ve Bd sung nhan tao nude
dudi dit ciia khu vuc Ddng Nam A o viing cit Binh Thuan, b) Dinh gii he phuong phap va
bieu qui ciia quan ly ngudn nude thdng qua cie cdng nghe bd sung nude dudi dit, c) Chuyen
giao cie kien thirc vi kinh nghiem cho cic nha khoa hgc Viet Nam ve ting cudng nguon nude
dudi dit bing bd sung nhan tao, d) Cung cap nude chit lugng tdt cho cdng ddng din cu d
nhirng viing hay bj ban hin, e) Lira chgn eic giii phip quin ly bd sung tang chira vdi muc tieu
cung cap nude trong bdi cinh cua bien ddi khi hiu d Viet Nam.
f>./T"

' •'(

'"''

Hinh 1. Vi tri khu virc nghiin ciru
Viing nghien cim li khu vue ven bien cua tinh Binh Thuin (hinh 1) vi diy li mdt
trong khu vuc khd nhit eua Viet Nam. Theo sd lieu mua thu thip tai tram Phan Thiet trong
thdi ky 1925-2007, lugng mua trung binh hing nim li 1,112 mm/nam, vdi cue tieu la 650
mm (1977) vi cue dai la 2,017 mm (1932). Do lugng mua it keo dai trong thdi gian 4 thing
(tir thing 12 den thing 3) nen khu vuc nghien ciru bj khd ban trong sudt thdi gian nay. Trong
khi dd miia mua ngin, nhung lugng mua ldn nen cd den 70-80% chiy tren be mat. Chi mot
lugng nhd dugc thim xudng cie cdn cit. Chi cd nhirng sdng ldn mdi cd nude trong miia khd
nhung nhin chung nude rit due vi bj nhiem man.

DAC DIEM THUY VAN VA DIA C H A T THUY VAN
Viing nghien ciru duge hinh thinh bdi cic di goe ryo-dacitic tao thinh cie ddi nim
cich biet (eao den 300 m so vdi mue nude bien), phii len tren cie di gdc niy li cic trim tich
Pleistocene trung {vQ\^) bao gdm eit thach anh miu niu dd kich thude trung binh.tao thanh
cae dun cit eao den 200 m so vdi mue nude bien; Cie trim tich bien Pleistocene trung he tang
Ma Lim (mQf/»/) bao gdm eat thach anh ilmenite. Cac trim tieh biin Pleistocene trung he
tang Phan Thiet (rriQ i pt) bao gdm cit thach anh miu ving dd chira biin vi set d cac mirc do

khie nhau; Cic trim tich Pleistocene thugng (vQ,^), la cie cit thach anh ma ving dd, kich
thudc hat trung binh; Cie trim tich Holocene dudi (vQ2'"^) li cit thach anh hat nhd miu tring
173


Tieu ban: Cdc Khoa hgc ve Trdi ddt

ISBN: 978-604-913-016-8

din ving nhat. Cae trim tieh niy tao thinh eic dun eit miu dd vi tring (cao den 200 m so
vdi muc nude bien) khi phd bien trong vimg ven bien khu vue phia Bie Phan Thiet (hinh2va3).
ii.SC Dl£.M D|.\ TASC \ A TIUCH HOC' VtNG C.lM6lltMiriVN0SrttK\l

SO D 6 BIA CHAT THUY VAN ViNG CAT VEN BIEN TINH BINH THUiN

j , j ^

Dag«(no
Mi;c fsifc fi«i trong cAn ;.il

Hinh 2. Sa dd dja tdng vd thgch hgc khu vuc
nghien ciru

Hinh 3. Sa dd dja chdt thuy vdn khu virc nghien cuu

Do lugng mua phin bd khdng
deu, miia khd keo dii 4 thing (chi cd 23
mm tir thing 12 den thing 3 nim sau

(hinh 4)), nen viing nghien cim bj han
hin trong sudt miia khd. Ting chira nude
trong khu vue nhien cim li ting chira
nude Id hdng, khdng ip, cd chieu diy
thay ddi tir 40 den 60 m. Id ra tren mat tai
nhiing vimg ed dja hinh triing (ed chieu
cao khoing tir 20 den 30 m so vdi muc
nude bien) vi tao thinh eic dim liy, ho
0 Jan I Feb 0 Mar Q Apr | May 0 Jun | Jul D Aug | Sep | Oct 0 Nov 0 Dec ao nhu triing Tazdn, hd Biu Trang, Biu
Ndi. Ting chiia nude niy duge khai thie
Hinh 4. Lirgng mua tnmg binh nam a trgm Phan Thiet
bing eic gieng bom true tiep hoac cic
(1990-2009)
gieng dio sau tir 5 den 8 m.
Ket qui mudi ehuyen khio sit dja chit thiiy vin da duge thue hien trong khoing thdi
gian tir 2004 den 2009 di ehi ra ring eic tham sd hda ly eua nude mit va nude dudi dit trong
khu vuc nghien cim ed do pH nim trong khoing tir 4.8 - 8.5; nhiet do tir 26 °C din 34°C; do
dan dien dao dgng trong khoing tir 50 ^iS/em dlnl,500 fiS/cm; Ting do khoing hda khoing
tir 30 mg/l den 800 mg/l. Cie ket qui phin tieh hda toin phin vi ddng vj ben eic mau nude
mat vi nude ngirn trong khu vuc nghien ciru trong cic thdi ky tir 2004 din 2009 da chi ra
ring nude dudi dit trong eic ting chira ciia khu vue dii eit ven bien Binh Thuin li cie loai
nude khie nhau, die trung bdi qui trinh pha trdng phire tap (Hinh 5).

174


Hgi nghi Khoa hoc k\' niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Noi 10 2010

,

Groundwater in dr\' season

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Hinh 5. Biiu do Piper ciia cdc mdu nuac dudi ddt chirng td rdng thdnh phdn hda hgc ciia
nuac dual ddt chii yiu Id Natri Clorua vd hdn hgp nude nggt vai nuac biin (a) khdng cd su
phdn biit rd rdng vi thdnh phdn hda hgc ciia nuac dirai ddt trong miia khd vd mua mua. (b).
Cae ket qui phin tieh ddng vj ben Tritium cic mau nude ngim vi nude Biu Ndi chi
ra ring tudi eiia nude dudi dit trong khoing tir 20 den 40 nam. Cie ket qua phin tieh ddng vj
ben (0-18; H-2) chi ra ring nude dudi dit trong khu vuc nghien cim cd ngudn gdc tir nude
mua trong viing (binh 6).
Dua vio cic ket qua phin tich sd lieu khi tugng, lugng mua cd the dugc sir dung de bd
sung cho ngudn nude dudi dit trong khu vuc khoing 1.5x10 m /km /nim (theo ket qui quan
trie khi tugng thiiy vin trong thdi gian 5 nim tai khu vuc Biu Ndi vi Hdng Phong). Ty le
ngam khoing 50% lugng mua ci nim.
-8.0

-7.0

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Hinh 6. Cdc ddu hiiu 0-18 vd H-2 ciia nuac mua, nuac mat vd nuac dudn ddt trong khu vuc
nghiin cim

175


ISBN: 978-604-913-016-8

Tieu ban: Cdc Khoa hgc ve Trdi ddt

CHIEU DAY TANG

CHITA

Nl/OC

Mudi tuyen do siu Dien vdi he dien cue Schlumberger, khoing eich cue dai li 1000m
cho phep xie djnh do siu cua ting chira nim yong khoing tir 45 den 105 m.
Bin tuyin khio sit dja chin khiic xa vdi tdng chieu dii 8000 m ciing duge trien khai
vdi muc dich xic djnh chieu sau ldp di gdc hue hien. Cic ket qui phin tieh di ehi ra sir tdn
tai cua di glc ryo-daxit d do siu tir 60 den 140 m ben dudi be mat.
Mat cat dia chan tuyen T4 - Bac BinK

j

Hinh 7. Mat cdt dja chdn khue xg thi hiin rd bi mat dd gdc trong khu vuc nghiin cim.
Cie ket qui nghien cim ting chira nude trong khu vue mdt lin niia duge khing djnh
thdng qua cic ket qui khoan (hinh 8) vi chi ra tang chira nude ehinh trong khu vue dun eit
ven bien Binh Thuin li ting ehiia nude khdng ip ed chieu diy tir 30 den 70 m. Muc nude tinh
dao dgng trong khoing tir 0.6 den 26 m ben dudi be mat.
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At>s<>lllle cte^'otion at [jlotan] stliLlcc
ICS-AN ,

23.7

Baseline of bed-rock

Hinh 8. Mat cdt khu vuc bdi giing khoan Bau Ndi

176


Hgi nghi Khoa hgc kv niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi JO/20 JO

THI NGHIEM TANG C H I T A N I T O C
Biu Ndi duge chgn lim vj tri thir nghiem de in Quin ly bd xung tang chira nude
(MAR) (Hinh 9). Do vj tri niy gin xi Hdng Phong, noi bi han hin keo dii trong mudi nim
qua.
Hd Bau Ndi duge binh thinh mdt cich tu nhien tir thing 11 nim 1999 do mue nude
tTnh trong ting chira khdng ip ding eao, dd li ket qui sir ngam nude mua true tiep xudng ting
chira thdng qua cic dun cit trong sudt 30 nim (do viee chat phi rirng). Tai khu vuc niy mdt

Id khoan khai thie nude KS-BN phuc cho xa Hdng Phong vi bdn Id khoan quan trie di dugc
thiet ke (Hinh 10). Cic kit qui quan trie cho thay sir thay ddi mue nude d Biu Ndi giira miia
khd vi miia mua khdng ding kl. Cie mau nude duge thu thap ei d hd Biu Ndi vi d Id khoan
khai thie KS-BN chi ra bim lugng nitrates dao ddng tir 0.3 - 17.0 mg/l. Vi hd Biu Ndi dugc
ehii yeu dinh eho chin nudi gia siie vi the him lugng vi khuin Coli rit cao ci d nmioc trong
hd lin nude hiit tir gieng khoan, vi the liy nude niy eung cap eho sinh boat eua nhin din thi
se khdng dim bio ve sinh.
De dim bio ed nude chit lugng tdt dii de cung cip eho sinh boat, edng nghe thim qua
diy (bank filtration) da duge de xuit ip dung trong khu vuc niy.
so o6 H6 T H 6 N G GI^'NG K H O A N PHUC VU B O M THCT NGHigM

A

QT-BN

^^p^^yw^

;—^

».76m
I
Ki-BN

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QSI

25

QSIV(lm)

-^

QSIVOm)

u

L 6 khoan khai t h i e

L A khoan q u a n sdt

C l f n g dAo

Hinh 9. Vi tri hd Bau Ndi

Hinh 10 Sa do cdc Id khoan khai thdc nuac vd
quan trdc a Ban Ndi

Mdt thi nghiem ting chira di dugc tien hanh bing cich bom hut thi nghiem 162 ngiy
vdi luu lugng 2.4 l/s, nhim hai muc dich: Xic djnh cac thdng sd dja chit thuy vin ciia ting
chira (he sd dan nude, he sd thim nude, luu lugng, van tdc dich ehuyen eua nude dudi dit),
tren co sd dd ed the danh gii diing ve tiem ning cua tang chiia nude dudi dat; Ap dung cdng
nghe thim qua diy de nang eao chit lugng nude dudi dit (giim him lugng E-coli);
Trong qui trinh thi nghiem, 33.600 m^ nude dudi dat da dugc hiit. of groundwater was
abstracted. Ha thap mue nude sau qui trinh bom thu nghiem tai cic Id khoan khai thac vi
quan trie nhu sau: KS-BN = 2.8 m;QT-BN=0.38 m;QSI=024m;QSn=0.15 m;QS3=030m
Dua tren ket qui bom thi nghiem, eic tham sd dja chit thiiy vin dugc xic djnh bing
cae phuong phip Tbiem-Dupuit va Cooper-Jacob (ha thip-thdi gian vi ha thap-khoing cich).

177

ISBN: 978-604-913-0iu

Tieu ban: Cdc Khoa hgc ve Trdi ddt

va phuong phip hdi phuc Theis- Jacob (bing 1). Ket qui ehi ra ring he sd dan nude kD: 230
- 594 m^/ngay, he sd tham k: 7.8 - 13.7 m/ngay, he sd nhi nude trgng lire: 0.16-0.18.
Cic miu nude dugc thu thap bing tuin de phin tich vi sinh, hda toin phan. Ket qui
phin tich chi ra ham lugng nitrates vi E-coli giim di theo thdi gian.
Bit diu tir thing 7/2006 gieng khai thie KS-BN di duge bom ve tram bom xa Hdng Phong de
eung cip ninioc udng eho nhin din vdi luu lugng 220 m /ngiy.
Bdng 1: Hi sd ddn nuac, he sd thdm vd hi sd nhd nuac cua tdng chua khdng dp
Phuong phip tinh toin

Thiem-Dupuit
Cooper-Jacob (ha thip-thdi gian)
Cooper-Jacob (ha thip-khoing cich)
Hdi phuc Theis- Jacob
Trung binh

He sd thim
k, m/ngay

He sd din
nude kD,
m^/ngay
230
538
235

594
399

r

He sd nhi nude
trgng lire, \x

-

13,7
7,8
16,5
12,67

0,170
0,157
0,175
0,167

CAC OAI PHAP QUAN LY TANG CHITA Nl/OC KHU VyC VEN BEEN BINH THUAN
Dua tren cic ket qua nghien cim tir nim 2005 - 2009, biy giii phip quin ly ting chira
viing ven bien nhu sau:
Cac giii phip niy dugc dua tren tieu chi: khdi lugng nude cung cip (mVngiy), chit
lugng nude, do tin cay ve cip nude, gii thinh, do ben trong van hinh vi tieu hao ning lugng,
mirc do nghien cim di hoin thien trudc khi triln khai du in, tdc do cd thi triln khai du in
trong thue tien vi tic ddng cua du an tdi mdi trudng
- Bom hut nude 370 m^giy d bai gilng khoan khu
vuc hi Biu Ndi.
- Khai thie nude d Biu Ndi vdi luu luong

2.700 m /ngay tren mot tuyen gieng dii 1
km doc Bau Ndi.
- Bom nude tir Bau Trang ve hd Biu Ndi
ting cudng va phuc hdi nude ngudn nude dudi dit
trong khu vuc nghien ciiu
•>

Soug Liiy

u Ti'jtng

Hdo2 Pboiie

rrdng

BBU

Noi

Eig II Distribution of seven options on MAR
Hinh II. Vi tri cdc du dn MAR cd thi triin
khai tgi viing cdt huyen Bdc Binh di cdp nuac

r

r

'

- Bom nude tir Sdng Luy ve triing Ti Zon

de bd sung bang bdn tham.
- Bom hiit nude tir ting chiia d khu vuc Bau
Trang (bank filtration) ve Bau Ndi.
_ j ^ ^ g^^ ^^^, ^^^ .hiia trong cac ao, hi
hoac nap xudng qua cac Id khoan trong khu
vuc xa Hdng Phong.
- Khai thac nude dudi dit tir cac suoi khu
vuc ven b i ^ trudc khi chimg thoit ra biin.

178


Hgi nghi Khoa hgc kv niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi JO 20JO

KET LUAN
De lira chgn duge eic giai phip quin ly ting chira nude trong khu vue nghien cim, can thiet
phii tien hanh ddng thdi eic khio sit dja chit thiiy van, dja vat ly, liy miu phin tich hda toan
phan, ddng vi ben, khoan khai thie thir nghiem kit hgp quan trie chat lugng nude, muc nude
ha thap, xic djnh cie thdng sd dja chit thuy van eua ting chira,...xic dinh ngudn nude de bd
sung eho ting ehiratren co sd cie kit qui nhin duge se lira chgn giii phip phii hgp vdi vimg
nghien cim.

TAI LIEU THAM KHAO
1. Dillon, P.J. (2005). Future management of aquifer recharge. Hydrogeology Journal, 13
(1)313-316.
2. Nguyen. T.K.Tboa, Giuseppe Arduino, Peter Dillon, Nguyen. V.Giang, Phan T.K.
Van, Bui T.Vuong (2006). Fighting against desertification; Groundwater Artificial
Recharge in Binh Thuan Province, Viet Nam. Project Report of Vietnamese Academy
of Science and Technology to UNESCO at Mexico.
3. Nguyen Thi Kim Thoa, Phan Thj Kim Vin, Nguyen Van Giang, Biii Tran Vugng

(2010). Nghien cim co sd khoa hgc vi cdng nghe quin ly bd sung ting chiia nude d
Viet Nam. Nha xuat bin Vien Khoa bge & Cdng nghe Viet Nam.

179