Asia Regional Planning Meeting4–5 May, 2016

Efficient use of limited water resource:Safe Reuse of Wastewater (grey water) in Agriculture

Mukund Patil and Team

International Crops Research Institute for the Semi-Arid Tropics,

Patancheru, India

Outline

Introduction

•Why? How? What?

Constructed wetlands as decentralized wastewater treatment system

•Domestic wastewater

•Bio-refinery wastewater

Outputs

In developing countries, a large portion of population resides in villages where formal waste management systems do not exist.

Recycling and reuse of available waste in villages provides sustainable solutions for a waste management system and reduces environmental degradation.

Inappropriate reuse of untreated wastewater is unsafe for farmers and consumers.

WHY? … illustrated

Water Scarcity

Wastewater treatment at Villalge level

How?

Low cost and less maintenance methodologies for wastewater treatment

Involvement of community based organization for wastewater treatment and reuse

Integrated Water Resources Management.

Wastewater treatment and reuse as business model to ensure sustainability and income generation

Regeneration: Decentralized wastewater treatment system for village or small community.

Substitution: Reuse of treated water

• Non-edible crops such as lemongrass

• Fodder crop

Reduction: More crop per drop

Business model

• Operated by SHGs or other CBOs

• Income generation by selling fodder and other by-products

What?

Better management of water, land and crops to develop viable and sustainable Green Economy

Integrating Bio-treated Wastewater Reuse with Enhanced Water Use Efficiency to Support the Green Economy in EU and India

Water4Cropswww.water4crops.org

Water4crops-EU-FP7

• Coordinator: Dr. Antonio Lopez, IRSA-

CNR

• EU Consortium: 5 Universities, 8

Research Institutes, 7 SMEs, 2

Consultant Comp

Water4crops-India-DBT

• Coordinator: Dr. Suhas Wani,

ICRISAT

• India Consortium: 2 Universities, 4

Research Institutes, 4 Industries, 1

Consultant Comp

Develop innovative bio-technological treatments for wastewater valorization and agricultural reuseImprove water use efficiency through improved agronomics, plant breeding and innovative irrigation techniques

Regenerate

Reduction

Sites

International Crops Research Institute for the Semi-Arid Tropics, Patancheru, Telengana

•Site for strategic research on wastewater treatment and reuse

Kothapally village, Medak, Telangana

•Village level decentralized wastewater treatment system and reuse in agriculture

Constructed wetland

Sedimentation / screen filters

Filter through layers of sand and gravels in wetland

Degradation of contaminant by

microbes and uptake by vegetation in

wetland

Reuse for irrigation

Constructed Wetlands:

human-made wetlands built to

remove various types of

pollutants present in wastewater

that flows through these systems

Researchable issues

Identification of efficient aquatic plant with respect to nutrient/contaminant uptake

Physical, chemical, and biological processes in constructed wetland

Low cost structures

Investigation of beneficial use of the plant biomass

Constructed wetland @ ICRISAT

Source: housing colony

Volume : 500 m3 per day

Wetland types• Free water surface flow

• Sub-surface flow

Performance of CW at ICRISAT

Water4Crops EU-India Joint Review Meeting, Montpellier, 15-16 Oct 2015

Percent Removal of Contaminant

Performance of CW at ICRISAT

Water4Crops EU-India Joint Review Meeting, Montpellier, 15-16 Oct 2015

Nutrient accumulation plants

Fiber content in plant biomass

Performance of CW at ICRISAT

Water4Crops EU-India Joint Review Meeting, Montpellier, 15-16 Oct 2015

Key findings

Ammonium removal varied from 10-70 %.

Nitrate removal varied from19-47%.

Phosphate removal varied from 40-77 %.

New weed species-Ageratum conyzoides field tested for high N removal.

High nutrient removal and low nutrient removal plants.

Wetland plants -Marigold provide income sources and Hybrid Napier, Napier and Para-grass have fodder value.

Source: ~500 households

Volume : Approx. 80 m3 per day

Initial assumptions for designing the DWT

• Average size of house hold = 5

• Average daily use of water per person = 40 liters

• Wastewater generation (percentage of water use) = 80%

• Hydraulic retention time = 3 days

• Width of wetland = 6 m

• Depth of wetland = 0.8 m

Total capacity: 40 m3/day

Filter media

– Gravel 40 mm size

– Gravel 20 mm size

– Gravel 10 mm size

– Sand

Vegetation

– Canna indica

– Typha

Constructed wetland @ Kothapally village

Constructed wetland for Bio-refinery wastewater

Capacity of wetland:

60 m3/day

Dimensions:

Constructed wetland = 20 m x 20 m x 1.0 m

Treated water storage tank= 20 m x 20 m x 1.5 m

Type:

Vegetated submerged bed

Filter bed:

Sand (25 cm thick)

Gravel 10 mm size (25 cm thick)

Gravel 20 mm size (25 cm thick)

Gravel 40 mm size (25 cm thick)

Vegetation:

Napier Bajara (Penisetum purpurem x Pennisetum

americanum)

Canna indica

Water source:

ETP effluent

Key Outputs

Team for research on wastewater treatment and reuse

Constructed wetlands: 15 (Telangana and Karnataka)

Agaretum conyzoides for use in constructed wetland.

Publications:• Articles: 5

• Conference paper/presentations: 5

Scaling-up in Bhoosamrudhi and watersheds projects

Thank you

How can it be implemented through a green business model?

What has been implemented so far?

Constructed wetland at Kothapally village in India. Treated water being used to irrigate one hectare farmland.

Farmers are trained to maintain vermicomposting

units (left). Biogas generated from waste is used for

cooking and lighting in Lucheba watershed in China

(right).