Updates on Domestic Wastewater
Management in Sri Lanka
Himali Karunaweera
Deputy Director
Environmental Pollution Control Unit
Central Environmental Authority

The 16th WEPA Annual Meeting 2021 (online)1

Content
1. Facts and statistics of domestic wastewater
management
2. Regulatory Framework for domestic wastewater
management
3. Issues and challenges
4. Future targets/plans for proper domestic
wastewater management

2Sanitation Type & Estimated Population Coverage(Principal Source of Drinking Water, 2012, Census of population and housing, Department of Census & Statistics – Sri Lanka)

Type of Sanitation

Estimated Population Coverage(Nos)Percentage %486,329

2.4

Onsite sanitation facility

17,021,528

84.0

Other sanitation(includes sharing withanother household, common/publictoilet)

2,411,383

11.9

Unknown sanitation type (not using atoilet)

344,483

1.7

Piped sewerage facility (off site)

3

Sewer Treatment Facilities in Major Cities
Sewerage System

1

Greater Colombo
Sewerage SystemCityPopulation
coveredColombo
Dehiwala/

331,500
65,000TPCapacity/M3/d

2 Ocean outfalls inCMC system

Mt. Laviniya
Kolonnawa

60,000WWTP Process

OperatedbyCMC2Kataragama

Kataragama

20,0003,000

3Hikkaduwa

Hikkaduwa

500+60commercial

1,040

4

Rathmalana/Moratuwa

Rathmalana

17,000Complete treatment

NWSDB

5

Jaela/Ekala

Ja Ela20,000+408
industries
10,5007,500

Complete treatment

NWSDB

6

Greater Kurunegala Kurunegala

43,0004,500

Complete treatment

NWSDB

7

Greater Kandy

55,000+150 14,000 Complete treatment,000(floating)

NWSDB

Kandy

Total population covered

605,968

Aerated lagoon with NWSDB
maturation pond
Facultative& NWSDBMaturation pond

4

Kataragama Aerated Lagoon

5Sewer Treatment Facilities in Major Housing Schemes
Housing Scheme

No ofConnections

1Soysapura
connected toRathmalana

1,987

2

Mattegoda

1,154

3

Jayawadanagama

4

TPcapacity/m3/dTreatment method

Operated by8,345

Imholf tank +Trickling filter
system now connected toBNR system

NWSDB

4,846

Waste stabilization pondsystem

NWSDB

669

2,809

Connected to CMC sea out
fall at Wellawatta

NWSDB

Maddumagewatta

315

1,323

Connected to CMC sea out
fall at Wellawatta

NWSDB

5

Raddolugama

2,045

6,000

8,589

activated sludge system

NWSDB6Hantana

394

550

1,654

Imhof tank combined withTrickling filter

NWSDB

7Royal Park

249

1,045

Connected to CMC sea out
fall at Wellawatta

NWSDB

8

Kuruminiyawatta

202848Connected to CMC sea out
fall at Wellawatta

NWSDB

Total

7,015

29,459600

Population
Coverage6

Wastewater Treatment Plants in Export Processing Zones
Export Processing
Zone

TP
capacity/m3/dTreatment method

Operatedby

1

Biyagama

21,000Mechanically Aerated lagoon system,oxidation ditch system

NWSDB

2

Seetawaka

9,900

Oxidation Ditch System

NWSDB

3

Koggala

675

Activated Sludge Extended Aerationsystem

NWSDB

4Katunayaka

3000

Flow through Aerated Lagoons system

BOI5Mirigama

400

Activated Sludge Extended Aerationsystem

BOI6

Wathupitiwala

900

Sequencing Batch Reactor system

BOI

7

Polgahawela

450

Oxidation Ditch system

BOI

8

Mawathagama

500

Oxidation Ditch system

BOI

9Horana

1,000Rotating Biological Contactors system

BOI

10Malwatta

450

Oxidation Ditch system

BOI

500

Oxidation Ditch system

BOI

11

Mawathagama EPZ
7Seethawaka Wastewater Treatment Plant

8Sewerage projects in pipeline 2021 onwards
Sewerage ProjectPopulation tobe covered1Negombo (SHIFT) Project

70,0002Jaffna City Sanitation Project

40,0003

Dehiwala Mt Lavinia Sewerage Project

110,000

4

Sri Jayawardenepura Kotte Wastewater Disposal
Project

112,000

Total

332,000

9Issues in Onsite Sanitation

••
•••
•
•
•
•

On site Sanitation commonly found in;Apartment buildings
Schools
Religious institutions
OfficeIndustrial, and commercial buildings
Shopping malls
Parks, Recreation or vehicle parks
Train and bus stations
Hotels and restaurants

 located in river reservations. & discharge in to waterways without treatment.
 Location of Apartment complexes and houses without proper approval procedure No space / facility for wastewater discharge or soakage
 Haphazard disposal of domestic wastewater from Gully sucker services.
 No access roads for gully sucker services.
 No responsibility over the management of WWTP once the operation starts.
 No proper sludge management
 Package type WWTP, capacity is not adequate Ground water pollution is not monitored.
 Pollution due to hotels along coastline- faecal pollution in coastal water.
 Domestic wastewater generated from hospitals with infectious diseases
10Domestic waste discharge to Kelani river11

Regulatory framework for domestic watermanagement• The Constitution of Sri Lanka (1978) Article 28; states that theexercise and enjoyment of rights and freedoms is inseparablefrom the performance of duties and obligations andaccordingly it is the duty of every person in Sri Lankato protect nature and conserve its riches• Parliament Acts/Laws
 National Environmental Act No 47 of 1980
 National Water Supply & Drainage Board Law No 02 of 1974
 Urban Development Authority Act No 41 of 1978
 Marine Environment Protection Act No 35 of 2008

• Provincial Statutes• Local Governmental Authority Laws
12

Statutory Organizations Involved in Sewerage Management
Department/Statutory Organization Related toSanitation Sector

Functional Areas and Responsibilities Relevant to Sanitation
SectorCentral Environmental Authority (CEA)

1. Regulate, maintain & control the quality of the environment.
2. Implementation of policies, plans and programs in respect ofenvironment and natural resources

National Water Supply & Drainage Board(NWSDB)

1. Formulation of policies, programs, projects based on national
policy in respect of water supply & sewerage services and provide
assistance in implementation of such programs and projects.
2. Investigation, planning, design, construction, O&M of watersupply and sewerage services.

Provincial Councils (PCs)
Municipal Councils (MCs)
Urban Councils (UC)
Pradeshiya Saba (PS)

1.Implementation of policies, plans and programs related tosanitation services in respect of Provincial Councils and Local
Government Authorities
2. Government functions relating to Local Authorities
3. Granting loans to Local Government Authorities for public
utility works.

Marine Environment Protection Authority(MEPA)

Prevention of marine pollution

Urban Development Authority (UDA)

1.Formulation of policies, programs and projects in respect ofurban development and assistance in implementation of suchprograms.
2. Urban planning and development,.
3. Assist Urban Local Authorities to improve urban Infrastructure
facilities.
13

Regulation / Procedures to control Industrial/ Domestic
wastewater – Central Environmental Authority
••
•
•
•

•
•

Prescribed projects (large scale) need to obtain approval through EIA /IEE
process under regulation No.772/22 dated 24.06.1993.
Environmental Consultative Committee for Apartments of floor area morethan 10,000m2
Issue Environmental Recommendations for siting ( approved through aTechnical committee for approval of siting of apartments and buildings floorarea less than 10,000m2)
Regulation on Prescribed Activities for which an Environmental Protection
License should be obtained Gazette No 1533/16 dated 25.01.2008.
Environmental Protection & Quality Regulation(Effluent Discharge standards)
No 1534/18 dated 01.02.2008- 01.02.2008- 07 categories of standards
including sewer discharge standards to dispose wastewater in to commonsewers.
Registration of gully bowers handling wastewater generated from PrescribedActivities as per Gazette No 1533/16 dated 25.01.2008.
Guidelines for disposal of sludge generated from sewerage treatment plants.

14

Regulations/Guidelines/Procedures followed at present byother institutions
 The Urban Development Authority Act, No 41, 1978, states that
construction should be done according to rules and regulations.
 Municipal Council, UC or PS control and regulate all building activities in
the area of its authority. Anyone engaging in building activities mustobtain a building permit from the relevant local authority.
 A building permit is valid for one year and can be renewed for two years[Regulation 10 (06)]. Section 3(1) of the Act describes the “UrbanDevelopment Areas” which requires building permits.
 The Technical Officer or Public Health Inspector(PHI ) inspects the siteand determines if the building project meets water supply and sanitary
guidelines (such as, SLS 745 Part II (2009), NWSDB design manual D7, PHIManual, National Policy for Rural Water Supply & Sanitation and UDA
guidelines issued for housing projects).
 Specific disposal standard for NWSDB pumping stations
 Issue permits to dump waste in to the ocean by MEPA
15Environmental Consultative Committee for Apartments Approvals granted(floor area more than 10,000m2 )Year

Number of Projects

2019

28

2020

15202105

Applications for Environmental Recommendations received during 2018 – 2019(floor area less than 10,000m2 )Wastewater
generation
Apartments with
20 – 100 m3/day

Not Recommend

Recommended withsuggestions

Recommend

1606

09

Land extent 15 P
No discharge point
Gardening as asolution
Discharge in todrains
No wasteManagement
procedures

Problems in treatment
method or need otheroptions for disposal.

WWTP with proper
disposal systems

Total
3116

Facts and statistics of Industrial wastewater
management
EPL status – 2019 & 2020

December 2019

December 2020
No. ofIndustries
EPL status

Category

No. ofIndustries

EPL status

A

13656

9631(71%)14152

8898 (63%)

B

10528

8840(84%)10616

7863 (74%)

C

25203

12769(51%)

26602

12756 (48%)

BOI

1188

844(71%)1155

688 (60%)

17

Status of some River Water Quality ( monitoring by CEA )2019 -2020
RiverNo oflocationsMonitoring
frequency

Year

Average
BOD, mg/l

1 Nilwala River8

once a month2019

1Average
COD,mg/l
5.6

2 Deduru oya

6once a month

2019

20.1

2020

Average Average
PO43- mg/l
NO3mg/l
0.9

<0.01

3.23

1.47

<0.01

2.95

26.06

9.97

<0.01

3 Attnanagalu

6

Once a month

2019

3.71

16.83

<0.01

<0.01

4 Menik River4

once a month

2019

1.67

14.63

0.15

<0.1

2020

1.78

12.92

0.15

<0.1

Oya

5 Mahawelii

8

once a month

2020

5.0

7.75

0.03

<0.01

6 Malwathu

3

once a month

2020

1.70

23.70

0.02

0.10

7 Badulu Oya

7once a month

2018

1.37

12.41

0.43

<0.1

2019

966.29

2.87

<0.1

2020

1.411.00.50

<0.1

River
Oya

8 Kelani River

17

Once a month

2020

720.8

0.0218

Status of some Lakes / Reservoir Water Quality ( monitoring byCEA ) 2019 -2020
Lake/ Reservoir

1 Kurunegala Tank

No oflocationsMonitoring
frequency

Year

Average
BOD,mg/l

Average
COD,mg/l

Average
NO3mg/lAverage
PO43mg/l

4

once a month

2019

7.43

25.06

1.10

0.03

2020

3.10

29.7

1.40

<0.01

2 Gregory Lake

7

once a month

2019

8.42

31.0

1.53

0.04

3 Wennaruwa Tank

3Once a month

2019

12.85

3.18

1.69

0.054

4 Diyawanna Oya

8once a month

2017

3.87

22.43

0.99

<0.01

2018

1.75

15.75

1.87

<0.15

2019

2.75

10.5

1.06

0.05

19

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21

Surakimu Ganga Programme• Major Environmental Issues Observed during the field survey
on February 2020 under the “Surakimu Ganga ” Project Discharge of domestic wastewater, agricultural runoff/contaminations &wastewater from livestock farming.
 Dumping of solid waste such as municipal, sludge debris ,chemicals
 River bed mining Aquatic alien invasive plants invade the riverbanks & water bodies
 Salt water intrusion during the dry periods Pollution of river bank due to the waste discharges by Sand/Soil washingactivities.
 Issues arising due to the river water damming Illegal construction in river reservations

22

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24

25

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“Surakimu Ganga” levels of operation & management
Inter ministerial Operation
Committee headed by Secretary
Ministry of Environment

District Coordination Committee
headed by District Secretariat

Divisional Coordination
Committee headed by Divisional
Secretariat

27

Issues / Challenges & future plans in Domestic Wastewater
ManagementIssues / Challenges•More than one institution has a responsibility in providing proper sanitation.
•Need coordination, technical and financial inputs for further development ofsanitation systems.
•Need cost effective small scale treatment systems.
•Up date and review regulations for proper domestic wastewater management
including inspections.

Future Plans•Implement “Surakimu Ganga Programme” island wide covering all 103 riverbasins.
•Quality & Quantity analysis of waste load along the river – (industrial &domestic) & restrict siting.
•New regulations for wastewater discharge ( review )•Amendments of the National Environmental Act and introduce load based
licencing scheme
28

Thank you!

29