Wastewater reuse – High Valleys in Bolivia

Martín del CastilloMunicipal environmental management

project (GAM)June, 2017

Middle income country

10 MM inhabitants – 70% in urban areas

30% in small or middle sized cities

3 different ecological floors

Sewerage

Wastewater treated

42 %

26 %

Regional overview – 15 small towns

Urban

Rural

Semi-arid climate. Precipitation: 500 - 600 mm / year

URBAN population: 68´000 inhabitants

Main sources of income: corn and peach production

Droughts reduce production capacities by 50%

15% EFFICIENT TREATMENT (7 WWTP)

11% DEFFICIENT TREATMENT (7 WWTP)

84% of the treated WW is used in irrigation

* OBD, OQD, salinization's risks

A lot of WW is already being reused(illegal connections)

re-use potential good treatment0

10

20

30

40

50

60

70

80

90

84

15

For every 100 liters of wastewater

69% GAP

The question regarding waste water is not “how to promote

its reuse”, but, “how to prevent sanitary risks produced by the

reuse of untreated wastewater”

Drivers and barriers

Re-use situation Ideal situationInformal agreements (verbal) among users

Formal agreements among users and municipalities

Some technical knowledge for reuse, but no knowledge about sanitary barriers.

Fulfillment of the law applyingsanitary barriers: farming restrictions, human exposure and quality of wastewater treatment.

Some undetermined mandates/competences among the different government´s levels. The water law is decontextualized

All the responsibilities should be clearly distributed and assumed by the stakeholders. There should be a clear legal framework.

Generic guidelines for infrastructure building

Specific guidelines for WWTP depending on re-use objectives

Policy building – use and reuse of water Water Ministry

Definition of quality parameters

Subnational Government

Authorizations National irrigation service

PPublic responsibilities regarding water

WW Treatment plants Local government

Definition of WW reuse

Community -Municipality

Quality parameters for

WW reuse???

WWho ddoes wwhat iin tthe rreal llive??

83 % of users with willingness to pay

Strong organization of farmersCommunity levelMunicipal levelRegional levelDepartmental and National level

Formal agreements for WW reuse

Municipalities Users / beneficiaries

Definition of use and conditions1/15

Formal agreement document

Fair tariffs – covering operational and maintenance costs

Unformal agreements for WW reuse

Verbal agreements14 families - ARBIETO

Irrigation shifts

With tariff:(ARBIETO) 5.00 [Bs/hr], less than 1Chf

Basic conditions:To be part of the community

17 families - CLIZA

Without tariff (CLIZA)

Efficient

Villa Carmen

Paracaya

Villa Lourdes

AcceptableArbieto

Ucureña

Colque Rancho

Tarata

UnefficientSan Benito Tolata

Toco

Unclear and undefined roles for the wastewater managementVery old and decontextualized lawHigh demand for wastewater: treated or raw.Need to choose the treatment (technology, infrastructure, etc.) depending on the expected use of wastewaterPromote sanitary barriers, depending on the quality of the treatmentNo WWTP´s design guidelines. Need to consider reuse right from the begining.

Conclusions

What is GAM/MEM project doing?

Improve services' quality

• Technical capacities: studies, operation and maintenance

• Pre-investments studies with a reuse approach

Co-responsibility

• Behavior change –better use of sewerage

• Services' payment

Strengthen service provider´s capacities

• Conflict sensitivity• Multilevel, multi-

stakeholder planning process

Sustainability of services: wastewater treatment, solid waste management

Key learnings to take home

1. How to deal with users expectations? – quality and quantity of the resource

2. Cost analysis for the reuse: who pays, how much, why?

3. Legal framework – responsibilities distribution - stakeholders

!Muchas gracias por su atención!