Union Jal Shakti Minister Gajendra Singh Shekhawat launched Sujalam 2.0, a nationwide campaign for greywater management.

What is greywater?

Liquid waste is water which has been used once and is no longer fit for human consumption or other uses where clean water is required. 

Broadly, there are two types of liquid waste or wastewater:

1) Blackwater is wastewater from toilets containing faecal matter.

2) Greywater or sullage is wastewater from bathrooms or kitchens. Greywater generally contains fewer pathogens than black water.

• Greywater includes used water from most of the domestic activities such as bathing, washing dishes and laundry. 

• Greywater is substantially less harmful than black water (water that has been contaminated by urine and faecal matter), but it still contains potentially hazardous chemical and biological matter. 

• It is estimated that around 15,000 to 18,000 million litres of greywater is generated daily in rural areas of India. If treated scientifically, greywater can be reused for several activities.

• Greywater management involves the treatment and reuse of domestic wastewater that has not been contaminated by urine or any faecal matter.

What options are available to manage greywater?

Soak pit: A soak pit is a dug-out pit filled with stones, preferably placed over burnt bricks. It has a porous-walled chamber that allows water to slowly soak into the ground. This is a relatively inexpensive technology and prevents stagnation of wastewater.

Leach pit: A leach pit is a brick-lined circular pit constructed in honeycomb masonry, with a diameter of approximately one meter that allows water to percolate into the ground. The pit should have a proper insect proof cover. Water should be led into the pit through a water seal trap, so that insect movement and mosquito breeding is avoided.

Kitchen garden: A kitchen garden uses gray water to grow vegetables, flowers or fruit in the courtyard of the house. This involves a simple surface irrigation system that requires low maintenance. It must be ensured that the gray water is treated before being let out into the kitchen garden which is achieved by passing water through a very simple device such as a silt and grease trap. A kitchen garden with a piped root zone system is an improved version of the basic kitchen garden. This involves underground irrigation using perforated polyvinyl chloride (PVC) pipes. Water is treated in the filter bed material surrounding the pipe, from where it directly reaches the roots of the plants.

Three tank: Three-tank filtration involves treating gray water through a three-part structure. First, water is passed through filtration a grease trap into an inlet chamber, next into a treatment chamber filled with gravel and then into a second treatment chamber filled with sand. The treated water can be stored in an underground tank for subsequent reuse.

Highlights of Sujalam 2.0 campaign:

• The ministry launched the first phase of Sujalam campaign in August last year.

• The new campaign will focus on creation of community and institutional greywater management assets.

• The minister said greywater if treated properly can be used in several ways like for farming and gardening.

• In view of providing water security to people, under the Jal Jeevan Mission, the greywater plan is being made an integral part of the village action plan. 

• Specific guidelines have been issued by the jal shakti ministry on the project.

• As part of the campaign, over six lakh villages will see intense activity on solid and liquid waste management.

• A joint advisory was also signed by nine ministries on how greywater management will be taken up at their level based on convergence model with all those who are directly associated in programme implementation.

• Under the campaign, the government plans to mobilise communities, institutions like panchayats, schools, anganwadis to undertake greywater management. 

• Greywater can be best managed where it is generated and turns into a major management and infrastructure challenge, if it is allowed to accumulate and stagnate.

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