1-The Groundwater Model for Part of the Water Supply Source … · 2020-06-03 · Narantsogt...

Journal of Environmental Science and Engineering A9 (2020) 77-89 doi:10.17265/2162-5298/2020.03.001

The Groundwater Model for Part of the Water Supply

Source Aquifer for the City of Ulaanbaatar Using

FEFLOW Simulation

Narantsogt Nasanbayar

Department of Environmental Engineering, School of Civil Engineering and Architecture, Mongolian University of Science and

Technology,Ulaanbaatar14191, Mongolia

Abstract: The cold, semi-arid environment shows a high variability in precipitation and river discharge, with a general tendency towards decreasing water availability due to increasing air temperatures and, thus, rising potential evaporation levels. The main watercourse near the city is the Tuul River, fed by precipitation in the nearby Khentii Mountains. However, due to the absence of precipitation during winter and spring, the riverbed usually runs dry during these seasons, and observations show that the dry period has been extending within the last years. For many decades, the water supply of Ulaanbaatar has been exclusively based on the use of groundwater in the Tuul valley. However, in parallel with the city’s development, the extended groundwater aquifer shows a clear decline, and the groundwater levels drop significantly. Therefore, a groundwater management system based on groundwater model and MAR (Managed Aquifer Recharge) is proposed and a strategy to implement these measures in the Tuul valley is presented. The groundwater model research purposes of artificially recharging the Tuul River aquifer are to provide information for future improvement in solving shortage water supply related issues and to find simple, low cost, cheap, and reliable flow control methods to eliminate the Tuul River drying out in low flow season. Key words: Finite difference, hydraulic head, conductivity, recharge.

1. Introduction

Northern Mongolia is the part of a semi-arid,

highly continental region where the Tuul River flows

through the boundary between the last of the Siberian

Taiga forest and Mongolian steppe lands bordering

with the Gobi Desert [1].The region’s main waterway

is the Tuul River, which is a right-bank tributary of

the Orkhon Riverflowing to the Selenge River in

Mongolia (See Fig. 1).The Tuul River basin is

bordered on the north by the river basinsof Kharaa

and Eruu, in the east by the Kherlen River basin,

in the south by the Central Asian internal

drainagebasin and the west of the Orkhon River basin.

The total length of the Tuul River is 742 km to the

Orkhon river confluence, catchment area is 50,400km2.

Corresponding author: NasanbayarNarantsogt, MEng,

main research field:Hydraulics.

The length of the river from its origin to the Lake

Baikal is 1,341km[2]. The origins of the river are Tuul

located on the southern slopes of the Khentii

mountains. The upper part of the river basin is

mountainous and almost entirely covered by forests.

The study area lies within the south western spurs of

Khentii-the main ridge of the mountain region withthe

same name. The district is characterized by erosionand

denudation relief due to the dismemberment spurs of

Khentii,the Tuul River valley and its tributaries. The

landscape of the area from the source of the river Tuul

to Ulaanbaatar city is determined by medium

mountains, usually withsoft smooth contours, and

below is mostly hilly ridges. The height of the

mountain peaks is in the range of 1,300-2,800m

altitude, and marks the bottom of the Tuul River

Valley in the district range of 1150 to 1450 M[3]. The

water level of the Tuul River fluctuates according to

D DAVID PUBLISHING

78

Fig. 1 Mainriver basins.

annual high

flow being 2

The clim

fluctuations

temperature

The aver

with absolut

minimum o

absolute mi

Low winter

permafrostin

recorded e

Ulaanbaatar

terminal site

clayey soils

seasonal fre

period is 18

under 0°C. T

the frosty p

respectively

Distribution

about 90%

The Grou

n water flow b

to low-flow

26.6 m3/s [2].

ate of the re

in daily an

and low prec

rage annual

te maximum

of minus 49

inimum air

temperatures

n soil 10-15

extreme cli

r city wette

e is due to ev

s are slight

eezing depth

7 days with

The average b

period are Oc

. Annual

of rainfall

of annual pr

ndwater ModUla

basins Mongol

cycles, with

egion is extr

nd annual am

cipitation.

temperature

39°С in July

9°С in Dec

temperature

s in the low c

m thick [4].

imate param

er station. T

vaporation an

to medium

[5].The dura

average daily

beginning an

ctober 9th an

rainfall

during the

recipitation fa

del for Part ofaanbaatar Us

ia—drainage b

its average w

reme, with l

mplitudes of

is minus 3

y and an abso

ember. Ave

is minus 4

cover snow c

. Below sho

meters in

The Ulaanba

d infiltration

heaving soil

ation of the

y air tempera

d lasting date

nd 14th of A

is 261mm

year is une

falling during

f the Water Susing FEFLOW

basins.(a) hyd

water

large

f air

.1°С

olute

rage

1°C.

ause

owed

the

aatar

; the

ls in

cold

ature

es of

April,

m[6].

even,

g the

war

dail

D

dom

win

and

Q

the

slop

foll

lith

A

wid

con

diam

resp

23c

29.0

rang

d

the

sou

upply SourceW Simulation

drological drai

rm period be

ly maximum

During the

minated by n

nds. The high

d autumn [8].

Quaternary al

Tuul River

pes of high

lowing sedim

ologic structu

Alluvial sedi

despread in t

nsist of mos

meters from

pectively. Bo

cm to 24cm. A

0m in thickne

ging from 12

dpQI (Diluvia

1st and 2nd

uth facing

e Aquifer for

nage basin ma

etween May

precipitation

year, in th

north west, n

hest wind spe

lluvial sedime

valley and o

h mountains,

ments are

ure:

imentaQII-IV:

the Tuul Riv

stly sandy l

m 2.3-3.2cm

ulders and gr

Alluvial sedim

ess in the vall

.0 to 15.0 m

al pluvial sedi

flood terrace

slopes of

the City of

ap of Mongoli

and Septem

n reaches 75 m

he Ulaanbaa

north and so

eed is observ

ents are wide

occur on the

, and in aq

distinguishe

Alluvial se

ver Basin. Th

loam and p

m to 17.

ravel have dia

ments are fro

leys, with mo

[9].

iments) are w

es of river va

high mo

ia; (b) map of

mber [7]. The

mm.

atar area is

outh easterly

ved in spring

espread along

south facing

quifers. The

d by their

ediments are

he sediments

pebbles with

0-22.0 cm,

ameters from

om 15.0 m to

ost sediments

widespread in

alleys, on the

ountains, in

f

e

s

y

g

g

g

e

r

e

s

h

,

m

o

s

n

e

n

water-collec

mountains.

The sedim

loam, sandy

and occasio

have depth

hillslope, wh

from 4.2 to 7

Tuul Rive

stratums: u

quaternary p

with sand,

with cemen

ganozoic era

Upper str

represented

and sand fil

areas of m

mechanical

gravel and b

the total wei

varies from

Silt and c

respectively

0.2%-1.1%[

Fig. 2 Long

The Grou

cting depres

ments consist

y loam, land

onal rare bou

of 13.0 to

hile the depth

7.8 m [9].

er alluvial dep

upper layerαQ

period, gravel

and lower l

nt, conglome

a [9].

ratumalluvia

by gravel p

lling. Sand is

medium-coar

analysis of

boulders are i

ght of the roc

18%-39% san

clay fraction

in amou

9].Asdepth o

itudinal hydro

ndwater ModUla

sions, and

t of pebbles,

waste, rock

ulders. The

o 18.0m de

h of diluvial

posits identify

Q2III-IV—alluv

l and pebble,

layer domina

erates, argilli

al formation i

ebble deposi

s usually asso

rse grained.

aquiferdepo

in range from

cks, while the

nd content to

ns in aquifer

unt of 0

of the gravelc

ogeological sect


at the feet

gravel with

k waste, boul

pluvial depo

epending on

sediments ran

y two stratigra

vial deposits

boulder fille

atesαQII-III1—

ite of Meso

is ubiquitous

its with boul

orted, with sm

According

osits contents

m 29% to 66%

amount of gr

o 12%-36%[9

either conta

0.4%-2.9%

content increa

tion along the


t of

clay

lders

osits

the

nges

aphic

s of

d up

—clay

ozoic

and

lders

mall

g to

s of

% of

ravel

].

ained

and

ases,

bou

part

con

sch

the

T

37

from

vall

thic

the

In

loca

cap

ther

to 5

surv

Thi

part

In

two

con

low

perm

bott

Tuul River aq


ulder fractiond

ticles increas

nsists of well r

ist, sandstone

mountain val

The thickness

m [9]. As a

m the sides o

ley. In som

cknessof the

flow of the ri

n the eastern

ate, cross se

acity of 10-1

re is marked

5m. Illustrati

veyed in Sep

ickness of se

t to the center

n most of

o-layer struct

nfined to dep

wer layers

meability. Th

tom sediment

quifer. Based on

e Aquifer for

decreases, an

ses.Detrital, f

rolled up, petro

e, quartzite, g

lley of the Tu

sof the upper

rule, there is

f the valley to

me places th

upper layero

iver Tuul (Se

n part of aqui

ections II-IIt

12 m. Near th

reduction in

ons of this w

ptember 1978

edimentary in

r.

the conside

ture. The u

osits of the s

having a s

he lower aq

ts of the rock

n data from R

the City of

nd the amount

fragment mat

oal presented

granite and o

uul River fram

stratum rang

s an increase

o the center a

here is an

on the main

ee Fig.2).

fer where sim

toIV-IV, hav

he east side

sedimentary

water table co

8 and March

ncreases from

ered site aq

upper aquifer

surface, to th

sufficiently

quifer is enc

k formation.

RIBES (1979) [9

79

t of silty clay

terial detritus

metamorphic

other rocks of

ming.

ges from 2 to

in thickness

and down the

increase of

channel and

mulation area

ve sustained

of the valley

thickness up

ontours were

1979 drawn.

m the eastern

quifer has a

r horizon is

he top of the

high water

losed in the

9].

9

y

s

c

f

o

s

e

f

d

a

d

y

p

e

.

n

a

s

e

r

e

80

Fig. 3 Tuul

Lower a

everywhere

close to the

pebble grave

filler in the f

the stratum,

can be tr

containing m

Thickness o

5-8m[9].

The thic

III-IIIto the

The minim

cross section

part of the a

aquifer, the

4 to 35 m or

the center of

Typically

the bottom l

on the dom

particle size

pebbles and

sand 25%-

particles 1.0

gravel, peb

The Grou

River valley m

alluvial strat

in the study

e sides of the

el sedimentat

form of silty

lenses or ba

raced almo

more gravel

of individual

kness increa

aquifer cente

mum thickne

ns II-II and I

aquifer. For th

thickness of

r more, usuall

f the valley.

, the deepes

layers. Lowe

mestic drinki

e distribution

d boulders 1

-44%, silt

0%-1.9% [9]

bbles and b

ndwater ModUla

monitoring cros

tum has de

y area except

e valley. It i

tion inclusion

clayey sand.

ands of sandy

st everywh

and pebbles

l layers vari

asesfrom the

er, western dir

ess is not mor

III-III, typica

he rest of the

the lower str

ly increasing

st interlayers

er ground lay

ing water in

within the f

18%-35%, g

particles 3

. With depth

boulders dec


ss section II-II

eveloped alm

t for some a

s represented

n of boulders

In the conten

y loam and l

here, someti

s and less s

ies from 1m

e cross sec

rection.

re than 5-15m

al for the eas

e large part of

atum varies f

from the side

situate well

yers, for exam

ntake site, h

following ran

gravel 25%-3

.1%-3.8%,

h, the conten

reases, and


I[9](see Fig. 2).

most

areas

d by

and

nt of

loam

imes

sand.

m to

ction

m in

stern

f the

from

es to

ls in

mple

have

nges:

37%,

clay

nt of

the

amo

bas

dep

aeo

carb

allu

cros

A

allu

pluv

aqu

of

sed

sed

gran

A

ubiq

cha

Inst

othe

B

diff

wat

are

enc

hea


.

ount of sand,

e alluvial

posited carbo

lian, and de

bon wasdisc

uvium in the

ss sectionsII-

Along the T

uvial sand an

vial sand,

uifers.Within

alluvial and

imentation w

iments and f

nites.

Alluvial aquif

quitous wi

aracterized b

titute on Bu

er organizatio

Both layers

fer in the com

tery.Whole a

unconfined a

losed in the

ad due to the

e Aquifer for

, silt and clay

formations

on or Neogen

luvial alluvia

covered in

eastern part

-II, V-V.

Tuul River

nd gravel wi

sandy loa

the study are

d diluvial de

waters of N

fracture water

fer valley Tu

ithin the

by report m

uilding Engin

ons).

are hydrauli

mposition of

aquifer and th

and contain f

lower aquif

presence in

the City of

y fractions in

of Tuul R

ne sediments

al formation

open wells

of the centra

valley occur

ith sandy loa

am deposits

ea, there are

eposits in ri

Neogene and

rs of Paleozo

uul river dep

Central so

material RIB

neering Stud

cally interco

water-bearin

he upper aqu

free groundw

fer, sometim

its roof loam

ncreases. The

River valley

s, sometimes

. Sandstones

s under the

al sources on

r quaternary

am, clay and

s occur in

groundwater

iver valleys,

d Cretaceous

oic rocks and

posits having

ource area,

BES(Research

ies(1979)and

onnected but

ng rocks, and

uifer stratum

water. Waters

es becoming

my lenses and

e

y

s

s

e

n

y

d

n

r

,

s

d

g

,

h

d

t

d

m

s

g

d

Fig. 4 Tuul

Fig. 5 Tuul

Interlayers.

both aquifer

Under th

depth of th

(winter-sprin

at the highes

On the s

groundwater

10-13m at h

The Grou

River valley m

River valley m

When drillin

r stratumswas

he conditions

he water ta

ng period) va

st within 0.5-

site of intak

r levels for

high standing

ndwater ModUla

monitoring cros

monitoring cros

ng wells the

s set.

s of undistu

able in the

aries from su

3m (summer

ke, depth of

r individual

groundwater


ss section III-I

ss sections IV-

overall leve

urbed mode,

lowest posi

urface 4-8m,

-autumn peri

f the decline

l wells reac

r table, 15-19m


IIIbased on dat

IVbased on da

el of

the

ition

and

od).

e in

ches

m at

its l

P

ban

Riv

loam

peb

of

form

Riv


ta from RIBES

ata from RIBE

lowest positio

Pluvial alluv

nk of the v

ver, composed

m and sand

bbles, boulde

the valley

mation valley

ver: Selbe, U

e Aquifer for

S (1979) [9]. (s

ES (1979) [9]. (s

on [10].

vial formatio

alley, from

d of alternati

d, containing

ers. Right ba

is dominat

ys from the

Uliastai river

the City of

ee Fig. 2).

see Fig. 2).

on, occurs

tributaries o

ing layers of

g crushed st

ank of the n

ted by pluv

e tributaries

rs and other,

81

on the left

of the Tuul

f loam, sandy

tone, gravel,

northern side

vial alluvial

of the Tuul

, as well as

t

l

y

,

e

l

l

s

82

diluvial-pluv

terrace outli

Deposits

of loam, san

pebbles and

diluvium for

lie the N

siltstones,

conglomerat

Groundwa

Fig. 6 Moni

Fig. 7 Grou

The Grou

vial formatio

ers.

attributable t

ndy loam, sa

boulders. Un

rmations or o

Neogene sed

sandstones

tes, shales) [9

ater table is

itoring and wa

undwater table

ndwater ModUla

on loops, po

to terraces pr

and with inclu

nder the abov

on the right s

diments (inte

s), carbon

9].

s currently c

ter supply wel

degradation b


ssibly with h

resent alterna

usions of gra

ve-described

side of the va

erbedded cl

n (sandsto

characterized

lls in aquifer fo

by abstraction


high

ation

avel,

low

alley

lays,

ones,

d by

sign

ope

wat

T

incr

side

area

T

alon

som

or water suppl

of water suppl


nificant draw

eration of gro

ter supply and

The depth of

reases in the

es of the val

as and varies

The bottom

ng the borde

metimes held

y city of Ulaan

ly wells [6,10].

e Aquifer for

wdown and

oup water int

d its enterpris

f the groundw

direction fro

ley its tribut

by the season

of the uppe

r of the upp

below, in the

nbaatar.

the City of

shortages ca

takes of Ulaa

ses.

water table f

om the Tuul

aries and in

n.

er layer, usu

er and lower

e lower layer.

aused by the

anbaatar city

from surface

l river to the

water intake

ually passing

r stratums, is

e

y

e

e

e

g

s

Fig. 8 UB aq

The gener

the valley, i

comparing to

depending o

2. Concep

Concept

modelling a

hydrogeolog

regime, wate

The city

exploitation

from an u

riverbed, ex

the Tuul R

main source

the capital c

For the g

also used R

from upper

section also

control reser

The wet m

June, July,

simulation

andonly us

The Grou

quifer zones cl

ral slope of th

is marked by

onormal undi

on location of

t Model

model is t

attempt and

gy, hydrolog

er balance in

y has been

wells that d

unconfined a

xploiting addi

River and trib

e of drinking

ity of Mongo

groundwater

RIBES monit

cross sectio

o dam axis

rvoir survey d

months with

August an

neglected

sed differen

ndwater ModUla

lassified by dis

he groundwat

y local increa

isturbed groun

f group of inta

the first im

requires d

gy, and gro

the area of si

supplied b

draw on grou

aquifer that

itional alluvi

butaries. Gro

water supply

olia.

model of aq

toring boreho

on from I to

cross sectio

data.

the highest

nd Septembe

winter sno

nce between


sturbance of G

ter table, dow

ase and decr

ndwater grad

ake wells.

mportant step

ata of geol

oundwater f

imulation.

by deep w

undwater sou

runs along

ial deposits f

oundwater is

y for Ulaanba

quifer estima

ole data star

o down IV c

on data of f

precipitation

er. A FEFL

ow precipita

n rainfall


GW gradient.

wn to

rease

dient,

p of

ogy,

flow

water

urces

the

from

the

aatar,

ation

rting

cross

flow

n are

LOW

ation

and

eva

3. F

N

are

whi

und

grou

of a

data

only

opti

T

T

zon

and

two

from

rest

side

T

wel

as E

N8,


aporation rate

FEFLOW S

Nowadays, gr

one of the

ich visualise

derground po

undwater, as

aquifers. Gro

a, but since

y software m

ion that is bo

They are two

MODFLOW

FEFLOW—

The water inta

ne is in the e

d has 22 well

o rivers Ulia

m south side

tricts west sid

e with Tuul ri

The data of g

lls 51, 68are

Eastern and W

, 58, as calibr

e Aquifer for

11mm/year a

Simulation

roundwater s

main tools f

e situation a

orous media

s well as rest

oundwater le

they cannot

modelling an

th fast and ac

modes of num

W—finite dif

—finite eleme

ake area with

astern part o

ls, located in

astai from no

are distribut

de with Uliast

iver.

groundwater

shown in Fig

Western boun

ration for grou

the City of

as inflow on

n of Model A

simulation an

for groundwa

and conditio

a for the p

toration and

evel loggers

be controlle

nd processing

ccurate [11].

merical mode

fferences met

ents method

h group of we

of the Central

n three rows.

orth side and

edand the are

tai river and s

drawdown in

g. 10 like red

ndary conditio

undwater fluc

83

top [1].

Area

nd modelling

ater aquifers,

on water in

protection of

development

collect more

ed manually,

g provide an

el software:

hod

ells named A

l source area

In this zone

d Khul river

ea of A zone

south-eastern

n monitoring

d banner used

ons and wells

ctuation.

3

g

,

n

f

t

e

,

n

A

a

e

r

e

n

g

d

s

84

Fig. 9 Conc

Fig. 10 Simu

The mai

reserves in

between Dec

flow, annua

Tuul river su

4. Sensitiv

The sensi

to identify w

to optimize

In the FEFL

by simulati

parameter i

and measure

The Grou

eptual model b

ulated elevatio

in source o

the water in

cember to Ap

allyfills river

urface water.

vity Analyse

itivity analyse

which parame

simulation re

LOW model

ion run and

smore sensib

ed groundwat

ndwater ModUla

box of inflow a

on of aquifer zo

of groundw

ntake area in

pril, wherethe

runoff infiltr

es

es for FEFLO

eter variation

esults [12, 13

some param

d it noted w

ble to the si

ter level.


and outflow wa

one A-A, yellow

ater operati

n the dry sea

ereis lack of r

ration loss of

OWsimulatio

n ismore sens

] and calibrat

meterswere va

which simul

imulation res


ater rate of aqu

w points are w

onal

ason

river

f the

nare

sible

tion.

aried

lated

sults

F

vari

cali

was

5. C

T

rese

thei

to s

the

para

be

mat


uifer.

water supply we

Fig. 11 graph

iation is mor

ibration of s

s chosen hydr

Calibration

The calculati

erves in acco

ir formation,

solve the loop

functional

ameters and

realized on

thematical m

e Aquifer for

ells.

h showed tha

re sensible in

simulated an

raulic conduc

n and Valid

ion of the o

ordance with

and also tak

p and inverse

reliability

obtaining th

nly in the re

models [14] de

the City of

at hydraulic

n simulation

d measured

ctivity.

dation

operational g

the above co

king into acco

e problems fo

of the assu

he initial con

esult of rea

escribing bot

conductivity

results. The

values ratio

groundwater

onditions for

ount the need

or evaluating

umed design

nditions, can

alizations of

th steady and

y

e

o

r

r

d

g

n

n

f

d

Fig. 11 Sens

transient filt

mode in ter

ofinitial d

determinatio

parameters w

the calibrati

DEV SQ

function, we

Validation

to determi

representatio

achieved b

process of

behavior of

between the

model. This

is to be acc

extended mo

compared t

intake wel

transformed

The Grou

sitivity analyse

tering ground

rms of unco

data ofhyd

on of c

was usedfor t

on Microsoft

average and

ere used.

n is to create

ne that th

on of the rea

y calibrating

comparing

f the system

em and the d

s process repe

ceptable. Va

odel area of

o the small

lls, input

to the real

ndwater ModUla

es of FEFLOW

dwater in a th

nfined flow.

draulic con

calculated

the calculatio

t Excel funct

d mean sq

the correct m

he model i

al system. V

g the mode

the model

m and using

data obtained

eats until the

lidation proc

central sour

FEFLOW

hydraulic

system (see


W simulation fo

hree-dimensi

The calibra

nductivity

hydrogeolog

on of reserve

tions—CORR

quared devia

model. It wasu

is an accu

Validation usu

el, the itera

with the ac

g inconsisten

d to improve

e model accu

cess builds m

rce of A-A z

model includ

head bound

Fig. 12). F


or groundwater

onal

ation

and

gical

s. In

REL,

ation

used

urate

ually

ative

ctual

ncies

e the

uracy

more

zone,

ding

dary

or a

vali

pres

area

a va

6. F

A

the

con

mor

fluc

part

pres

valu

resu

data

such

in s

suit

weu

200


r model.

idation, rever

sents as cha

a and ex bou

alidation.

FEFLOW S

As mentioned

upper laye

nductivity of

re suitable

ctuation simil

t of area in

sents ground

ues, andthe

ults (see Fig

a are similar

h as Fig. 13,

simulation tha

table in pract

used groundw

09 to 2011 sam

e Aquifer for

rse validation

anging small

undary condit

Simulation

d before, the

er is 330m/

the lower lay

results (se

larity of grou

n wells in s

dwater level

silver blue

g. 13).When

r and demon

, then we can

at shows resu

tice use. In t

water level lo

me as measur

the City of

n methodwas

-simulated a

ion well mon

nResult

hydraulic co

/day, and th

yer 30m/day

ee Table 1)

undwater lev

simulation. T

in manuall

lines presen

measured an

nstrate calib

n manage som

ults in comput

this FEFLOW

ogger data in

red data.

85

used, which

area to large

nitored as for

nductivity of

he hydraulic

[15], giving

) in visual

vel in middle

The red line

ly measured

nt simulation

nd simulated

brated curves

me scenarios

ter which are

W simulation

n years from

5

h

e

r

f

c

g

l

e

e

d

n

d

s

s

e

n

m

86

Table 1 Cal

Number of simulation

Cal

ibra

tion

5

160

162

vali

dati

on 170

176

Fig. 12 Exte

The Grou

libration and v

Eastern BC

Western BC

Monitoring wells

293-12

330-40

292-25

330-30 /1305.5- 132326\

500-40 /1305.5- 132326\

ended area par

ndwater ModUla

validation in FE

Well

68-1327.5

51-1310.34

N8-1315.64

58-1321.76

No. 68

No. 51

N8

No. 58

No. 68

No. 51

N8

No. 58

No. 68

No. 51

N8

No. 58

No. 68

No. 51

N8

No. 58

No. 68

No. 51

N8

No. 58

rt of aquifer A


EFLOW.

Correlation coefficient

0.952

0.890

0.917

0.923

0.979605

0.976686

0.936719

0.919286

0.972978

0.97307

0.840523

0.835059

0.979467

0.971521

0.900138

0.901302

0.987448

0.972535

0.952723

0.921597

-A zone for rev


Correlation

Sum of Correlation

3.682

3.812

3.622

3.653

3.653

verse validatio


Sum of monitoring wells

1.84

1.856

1.676

1.856

1.856

on.

e Aquifer for

Average square

Average square deviation

SA

12.28

7.74

1.79

3.16 24

10.78

15.83

7.03

8.03 4

10.22

14.67

5.8

6.72 3

10.63

48.05

6.69

7.15 72

11.28

50.75

9.19

8.88 8

the City of

e dev. Mean s

um of ASD

Mean squaredeviat

24.10

42.60

29.76

4.97 37.74

35.44

36.94

31.39

1.67 50.95

34.65

35.62

31.41

7.41 49.75

35.11

78.16

29.59

2.51 48.78

35.7

83.71

32.04

0.1 47.74

square dev.

e tion

Sum of MSD

134.20

154.71

151.43

191.64

199.15

Fig. 13 Gro

7. Discussi

In latest d

the consum

supply of

availability o

has become

considered

simulation a

model in upp

The simul

not as simpl

measuremen

as simple

conductivityw

When we

measured da

activities in

To recha

surface wate

low flow per

Aquifer in

drainage ca

underground

The Grou

undwater leve

ion

decades as th

mption of do

the city is

of water supp

a pressing iss

groundwater

and compare

per part of Ul

lation should

ler and result

nt. Therefore,

as possible

wasnumbered

eget good s

ata, then wes

FEFLOW pr

arge aquifer

er during hig

riod such as w

nfiltration rat

anal to study

d water flux

ndwater ModUla

el measured an

he city develo

omestic and

increasing

ply both now

sue. Therefor

r model bui

ed with meas

laanbaatar aq

d be as simple

ts should be

, some aquife

e. For exa

d equally in x

simulation re

should possib

rogram softwa

storage via

gh flow seaso

winter for wa

te from artifi

y percolation

x during se


nd simulated va

ops and expa

industrial w

intensively

and in the fu

re, in this pap

ilt in FEFL

sured results

quifer.

e as possible,

close to the

er data shoul

ample, hydra

x, y, z directio

esults simila

bly do follow

are.

a infiltration

on for use du

ater supply.

icially rechar

n of monito

evere Mongo


alues in wells.

ands,

water

but

uture,

per it

LOW

s for

, but

true

d be

aulic

ons.

ar to

wing

n of

uring

ging

oring

olian

wea

T

win

mel

T

and

wat

Rec

T

con

met

wea

F

incl

dive

buil

grou

8. C

T

hyd

dete

mon

293


ather conditio

To create ice

nter cold seas

lting during th

To understan

d recharge in

ter shortage

charge).

To determin

nventional

thods,and co

ather conditio

FEFLOW sim

luding chang

ersion drain

lding underg

undwater sou

Conclusion

The main par

draulic condu

ermined by

nitoring wel

3m/day in two

e Aquifer for

on.

storage from

son to increa

he dry season

nd the balanc

order to deve

s using M

e the most

and no

ombination o

ons.

mulated resu

ging rechargi

nage canals

ground ice d

urce areas.

ns

rameter to d

uctivity. The

RIBES [9]i

ll different

o layers (see T

the City of

m artificial so

ase groundwa

n of March an

ce between

elop strategie

MAR (Manag

t suitable a

on-convention

f them, in e

ults comparin

ing boundary

by old riv

dams, and st

determine sim

e hydraulic

in 1979 sho

values from

Table 1, Figs

87

ources in the

ater levels by

nd April.

consumption

es for solving

ged Aquifer

and efficient

nal MAR

extreme cold

ng scenarios

y conditions,

er channels,

toring ice in

mulation was

conductivity

ows in each

m 4m/day to

s. 15 and 16).

7

e

y

n

g

r

t

R

d

s

,

,

n

s

y

h

o

The Groundwater Model for Part of the Water Supply Source Aquifer for the City of Ulaanbaatar Using FEFLOW Simulation

88

Fig. 14 Hydraulic conductivity of the first upper layer.

Fig. 15 Hydraulic conductivity of the second lower layer.

Fig. 16 Hydraulic conductivity in x direction.

The Groundwater Model for Part of the Water Supply Source Aquifer for the City of Ulaanbaatar Using FEFLOW Simulation

89

To run FEFLOW simulation, some simplification

was applied in that the layers have the same hydraulic

conductivity.

The calibration is compared with the measured and

simulated results of hydraulic conductivity by

correlation coefficient and checked again by average

square deviation and average mean deviation. All

these results are then compared, calibrated and validated.

Calibration and validation demonstrate that

hydraulic conductivity of the groundwater aquifer on

the upper side of the central source of Ulaanbaatar in

upper stratum yields 330m/day; lower stratum yield of

30m/day is suitable for FEFLOW simulation [15].

The simulation provides information about future

improvements in solving Ulaanbaatar’s water supply

issues [17,18] in a simple, low cost and reliable manner.

For this purpose, create useful FEFLOW simulation to

understand natural hydrological conditions of the Tuul

River, that close to the natural hydrological regime

and groundwater flow. All simulation scenarios result,

and evaluation of MAR methods have beenwritten in

following article in Journal Water

(https://www.mdpi.com/2073-4441/11/12/2548) [1].

References

[1] Nasanbayar,N., and Morhlok, U. 2019. “Evaluation of

MAR Methods for Semi-arid, Cold

Region.”Water11(12):2548.https://doi.org/10.3390/w111

22548.

[2] Davaa, G. 2008.Surface Water Resources in Mongolia.

Ulaanbaatar, Mongolia.

[3] Gombo, D.,andErdenetuya, M. 2004.“Hydrological

Changes in the Upper Tuul River Basin.”In Proceedings

of the 3rd International Workshop on Terrestrial Change

in Mongolia, Tsukuba, Japan, 16-9.

[4] Dashjamts, D.2015.“Permafrost and Geotechnical

Investigations in Nalaikh Depression of Mongolia.”

Sciences in Cold and Arid Regions7(4): 438-55.

[5] Dashjamts, D. 2013.“Geotechnical Problems of

Construction on Permafrost in Mongolia.”Sciences in

Cold and Arid Regions5(5): 667-76.

[6] GIM (Geo-ecology Institute Mongolia). 1997.The

Research Works Report of Tuul River Water Reserves

Decreases Reason, Protection provision UB. Ulaanbaatar,

Mongolia: GIM.

[7] GIM (Geoecology Institute of Mongolia). 1999.The

Ecological Assessment of Tuul River. Ulaanbaatar,

Mongolia: GIM.

[8] GIM(Geoecology Institute of Mongolia).2010.The Report

of Water Quality, Aquatic Environmental Ecology Study.

Ulaanbaatar, Mongolia: GIM.

[9] RIBES(Research Institute on Building Engineering

Studies). 1979.Technical Report of EngineeringSurvey

TOM-2. Moscow: RIBES.

[10] Unurjargal. D. 2009.Report of Research Works on

Groundwater Monitoring Measurements Data. Ulaanbaatar.

[11] Kresic. N. 2007.Hydrogoelogy and Groundwater

Modelling(2nd ed.).Boca Raton, FL: CRC Press.

[12] Sltelli, A. 2002.“Sensitivity Analysis for Importance

Assessment.”Risk Analysis22(3): 1-12.

[13] McElwee, C. D., and Yukler, M. A.1978.“Sensitivity of

Groundwater Models with Respect to Variations in

Transmissivity and Storage.”Water Resources Research

14(3): 451-9.

[14] Anderson, M. P.,and Woessner, W. W. 1992.Applied

Groundwater Modeling: Simulation of Flow and

Advective Transport.London: Academic Press, 281.

[15] Nasanbayar,N. 2019.“Icing Phenomena for Managed

Aquifer Recharge (MAR) and Its FEFLOW Simulation

Result.”PMAS59 (1): 229.

[16] SIWRMM. “Strengthening Integrated Water Resources

Management in Mongolia.” Project.SIWRMM. Tuul river

basin integrated water resources management assessment

report. 2012.

Date post:	24-Jul-2020
Category:	Documents
Upload:	others
View:	0 times
Download:	0 times

1-The Groundwater Model for Part of the Water Supply Source … · 2020-06-03 · Narantsogt...

Documents