AYUBOWAN

1

Urbanization and Water
Quality Control for theSource of Water inColombo city, Sri Lanka
ByDr. R M S K Ratnayake
DirectorCentral Environmental Authority
Sri Lanka
2Democratic Socialist Republic of Sri Lanka

3

Beauty of Sri Lanka
SIHARAJA FOREST

4

AVUKANA STATUE

5WATERFALLS IN SRI LANKA

6

KNUCKLES

7LEAPORD

8

a. Introduction
 About Sri Lanka– Rich in Natural Resources– 103 Rivers Cover All Island– 9 Provinces and 25 Districts– Capital is Sri Jayawardenapura Kotte inColombo District– 65610 Km2 of Total Land Area– 20 Million Population– 2000 mm of Annual Average Rainfall Provides
131230 Millions m3 of Fresh Water Annually9b. Reason for Selection of theTarget Area
 Colombo is the main commercial andindustrial city in the island
 Highest industrial and population
densities
 Pollution loads to the water
resources are high Drinking water demand is high due
to population increase10

25 Administrative Districts of Sri Lanka

111. Socio-economical and Natural
Conditions of Colombo City
 Population
Population

198120012007

Colombo

1699241(11.4%)

2251274(12.0%)

2456000(12.3%)

Island14846750 18797257 20010000

 Population Density– Total Area 699 km2 (~1% from island)– Population Density
3513/ km2
– Island Pop. Density
320/ km2
12

Socio-economical….
Gross Domestic Products is $ 40.7 billion
 50% of GDP contribution is from Western Province
 Annual Average Precipitation- 2400 mm
 Accessibility to Tap Water System ~65% in Colombo
District
 Rest are from other sources, well water (31%), tubewells (1%) etc.
 Domestic Wastewater System– Colombo is the only city in Sri Lanka with sewagesystem– 80% of the Colombo city area has access to the sewersystem– Collected sewage discharge into the sea outfall without
any treatment (two places, approximately 1km and1.5km)– Rest of the people have individual septic tank/soakage
pit systems for sewage or domestic wastewater– Piped sewage facility in SL is 4% from population, site
sanitation or septic tanks is 80% and 16% is without
proper sanitation

13

2. Situation of Quantity andQuality of the Water Source 3 Production Centres in Grater Colombo

Water Supply System– Kelani River Intake at Ambatale– Labugama Compounding Reservoir– Kalatuwawa Compounding Reservoir

 Systems Provide 18 Million m3/day
 Total Consumers 2.0 Million
 65% of the Colombo District Requirement
14

Situation of Quantity and…
Name

Volume ofavailable
Water

Volume ofabstracted
Water (m3)Kalani River ~15
MCM/day
Ambatale(Averagerunoff)

512000

Labugama
Reservoir

15.4 MCM

62000

Kalatuwawa 8.9 MCM
Reservoir

37000

15

Situation of Quantity and…
 Water quality of intakes

Intake

BOD

COD

TSS

Heavy
metalspH

Kalani
river

21820

Pb .06 8.0
Cr <.01

Labugama 31910Pb 7.5
Cr <.01

Lalatuwaw 2a1712Pb 7.3
Cr <.0116

3. Effluent Load to the Sources ~30% from total industries are in Colombo
 More than 10% 0f the population is inColombo
 Pollution of water resources in the area arehighly threatened by pollution
 Industrial effluents of the area can bemanaged
 Domestic effluents and other non point
sources are difficult to control
 Stagnated water sources are highly
threatened by nutrient pollution, NO3- andPO417

Effluent Load to…
 Main wastewater receiving water bodies inColombo area– Kalani river– Beira lake (stagnated water body connected to the sea)
– Sea
 Wastewater could result from industrial anddomestic– Industrial effluents discharge directly or indirectly into
the Kalani river or its tributaries– Domestic wastewater including sewage
 Discharge into the sea outfall through sewer network Directly discharge into the Kelani river or Beira lake 18000 households in the beira lake catchment's area aredischarging sewage into the lake18

Effluent Load to…..
 Industrial effluent loads into Kelaniriver– Two common TP s in main industrialzones
 ~15000 m3/day (25% is sewage)
 ~10000 m3/day (25% is sewage) Treated effluents are conform to CEA stds

– Other industries
 Textile - ~35000 m3/day Food & beverages - ~35000 m3/day
 Chemical industries - ~15000 m3/day

19

Effluent Load to….
 COD loads from major industrial

sectors– 2 common treatment plants- ~6250kg/day– Textile industries- ~8750 kg/day– Food & beverage industries- ~8750kg/day– Chemical industries- ~3750 kg/day20

4. Current Measures on Quality
Control for the Water Resource Sources of Water Pollution in Colombo

Area– Non Point Sources– Point Sources Non Point Sources– Mainly from Domestic wastewater, agriculturalrunoffs etc.
– Difficult to apply laws and regulations directly– Difficult to control– Controlled by applying better land use pattern,
local government planning laws, awareness– Main responsibility is with local government
authorities (13 in Colombo, 4 MC, 5 UC, 4 PS)
21

Current Measures on Quality…
Laws on control of non point sources– NEA

 May require local authority to comply with recommendations

relating to the prohibition of the unauthorized discharge, emission
or deposit of sewage and the prevention of the discharge ofuntreated sewage into soil, canals or water ways.

– LGA laws

 The Government or any Municipal Council may, from time totime, cause to be made, altered, or extended such publicmain or other drains, sewers and watercourses necessary
for the effectual draining of the Municipality – MC 97
 Prevent obstruction of discharge of rain-water and drainage
to any natural watercourse, channel, lake or swamp
recognized for such purpose by resolution – MC 101
 Connection of private drain with any public drain withoutauthority is an offence – MC 103

22

Current Measures on Quality…
Options for discharge of sewage inColombo– Individual systems (within the premises)– Sewage network (discharge into sea out
fall without any treatment)– Common treatment systems(condominiums and schemes)– Illegal direct discharges to the water
bodies (specially from unauthorizedhouses/buildings)
23

Current Measures on Quality…
 Point Sources– Mainly from Industrial Activities– Points of sources can be identified– Can be minimized and controlled by laws anddifferent strategies
 Control measures/strategies on pointsources– Laws and regulations– Monitoring– Education and awareness24

Current Measures on Quality…
Laws and regulations on point sources– Mainly controlled by National Environmental Act (NEA) of 1980
 Central Environmental Authority (CEA) established in1981 for

implementation of the NEA

 Five main sections and section IV is on environment management

and protection– Two legal tools and discharge standards
 Environment Impact Assessment (EIA) - Section IV C

approving procedure for prescribed projects, due to sensitivity orscale

 Environmental Protection Licence (EPL) - Section IV A

all prescribed activities/industries need EPL for discharge theirwastes

 Wastewater Discharge Standards - Section IV B

discharging effluents shall be conform to the stipulated standards

25Current Measures on Quality…
 EPL process for waste discharging activities– 133 prescribed activities including wastewater
generating activities– EPL is a legal requirement to discharge waste into theenvironment– EPL issued only after conforming to the standards– Operation of an industry without an EPL is a punishableoffence Wastewater discharge standards– Two types of standards– Receiving environment- inland surface waters, irrigation,
coastal area, common TP– Type of activity- textile, rubber, tanning26

Some Important Water Quality ParametersTSS

BOD Oil &COD
GreasePesticide

FaecalColi form

Inlandsurface

50

30

10250

0.005

40

Irrigation

2100 250

10400

-

40

Marinecoastal150

100

20250

0.005

40Common TP500

350

30

8500.2-

Rubber- latex 100
std. 100

6050-

400400--Textile

506010250--Tanning- ISW 100
MC 150601001020250300-27

5.

Current Issues on Quality Control
for the Water Source Unavailability of zoning plan Unlimited discharges to the water sources Economical and technological issues onpollution control Encroachments and illegal constructions atreservations of the water sources
 Inadequacy of the existing laws andregulations

28

Current Issues on Quality….
 Unavailability of zoning plan

– Zoning plans are available only for 3 LGA s in
Colombo district– Not demarcated industrial zones– Difficult to control environmental pollution
 Unlimited industrial discharges to thewater sources– Gradually increase industries in major cities
due to infrastructure developments
29Current Issues on Quality….
– Waste loads to the water sources gradually
increasing in Colombo area
– Receiving capacities of wastes on water
sources are limited
 Economical and technological issues on

pollution control– Financial barriers on pollution control activities– Inadequacy of the available technology

30Current Issues on Quality….
 Encroachments and illegal

constructions at reservations of thewater sources– Most of the reservations/catchments areencroach by people and discharge theirwaste into the water sources– Difficulties on application of laws on them
– Unauthorized constructions at the riverbanks– No reservations are demarcated31Current Issues on Quality….
 Inadequacy of the existing laws andregulations– Existing law on waste emission is a commandand controlled system– No system to control the pollution loads ofindustries– Existing laws on domestic wastewater
discharge are weak
– Inadequacy of land policy to control
encroachments– Laws are not sufficient to control illegal
industrial activities within a short period

32Thank You33