Grey Water Conservation in Gajner

I´ve been in India for one month already but there is not much I could do for my project: The first week I stayed in Naddi for the induction; the second I came to Gajner, but I was following my pals to their activities (girls/boys club, ASP, YWA) and knowing the community, in order to learn about the cluster’s routine and the community itself; the third week we were back in Naddi for the Quarterlies (that trip is a nightmare and I’ve done it three times in three weeks), and then we came back and I started with my thing.

The idea is to treat the grey water we produce in our house (water from taps, shower, laundry…) making use of a biological filter to use it to water a small garden I will start soon.

I have a design of the biofilter. It consists on a two-step biological filter. The first step is a soil filter with anoxic conditions where the carbon will be reduced as part of the metabolic activity of bacteria attached to the soil and denitrification will take place. The second infiltration step will consist on a soil filter with oxic conditions, which I hope to arrange by planting one plant which name I ignore but is everywhere around here, growing even in soils flooded with wastewater. Also the lower amount of carbon after the first infiltration step limits the growth of bacteria in the second filter. Less bacteria need to breath less-> there is less oxygen consumption-> more oxic conditions.

Plant growing in a soil flooded with wastewater

The oxic and carbon limiting conditions enable for the growth of slow growing bacteria capable for degrading a big range of trace organic compounds, contained in soaps and detergents, and which have a dangerous impact once in the environment. The oxic conditions enable also for nitrification to take place.

I think I’ve found a soil with a good corn size after the physical analyses of several soils around our house. This soil is near the Gajner Palace. The idea is to have a corn size that allows the water to flow down the filters, without getting stucked (too fine corn size) or without flowing too fast (too big corn size). If this last possibility happens, the bacteria attached to the soil corns won’t be able to degrade the carbon contained in the water.

Materials used for the soil analyses of three different soils

The trouble is that this sand is a bit far of home, and it’s too hot to carry it here. Good news is I made friends with a shop keeper who gave me some nails for free. I brought chai to drink with him and he was so happy that he drove me back home with his tuk tuk (yes! He has a tuk tuk too). I asked him, and he will help me carry the sand with it.

I found all the materials I need for the set-up of the filtration system in Bikaner, thanks to Manoj’s help. Coming back to Gajner with Léa in the bus, carrying 4 huge bins (she also needed 2), food and 3 mattresses for the house was a real challenge. The set-up of the filtration train is still in process.

I’ve been learning how to make compost. I have built a compost box and started composting. For the moisture, the effluent of the biofilters will be used. Until they are constructed and in order to be able to start as soon as possible with the compost, we are saving the water used for cleaning the vegetables for this matter. The compost is very important, as the soil here is so poor. 

The garden will be in Manoj’s shop’s backyard, right below our house, and the filters will be situated along the height of the wall, so as to let the water flow with the gravity and avoid the need of external sources of energy, and to drip directly on the garden. I cleaned the backyard as it was full of plastic bottles and bins and waste in general, and I will also have to work on the soil. 

Manoj's backyard full of waste

The heat was too strong for cleaning the backyard, but some random super nice guys of the community helped me early in the morning, making it so much easier.

Improvised awesome cleaning team

The plan is to have the kids of the ASP to help me with the garden, to learn about gardening and about the importance of recycling water, especially in such a dry area. The ASP team is very happy with this idea. In order to let the rest of the community to know about the project, we will also paint the wall where the filter will be situated with an explanation of what is it about as a cluster activity and also with the ASP kids, this way everyone can see it from outside the backyard.

I want to thank all my cluster partners for their help because without them the implementation of this project wouldn’t be possible, as there are so many things I just can’t do alone. Thank you so much guys!!!

Lucía Villamayor - Spain

Bikaner Cluster Coordinator