Final preparations

Sunday 25th November

After another 5hr drive from Dhaka, we arrived at the site and admired our new sign:

We've also now got some gateposts being built and the beginning of some fencing:

Peeling off the formwork

Chopsticks for giants

We inspected the site and saw the finishing touches being made to the soakaway.  This is where any water draining out of the three beds with sand filters in will end up.

Detail of the soakaway - inlets from each bed and an overflow into a nearby ditch

 As ever the labourers had come prepared:

The labourers lunches - probably better than a meal-deal from Boots!

Tools, lunch and materials and transport.

Next I set up the weather station, much to the interest and intrigue of the others:

Putting it all together

Attaching it to a long bamboo pole

That should keep it out of reach of curious hands...

Then we attached the temperature sensors (ibuttons from Maxim) to the underside of each of the roofs, hanging down about 6inches.  

After lunch we started putting the filters together.  Firstly any stray leaves were removed from the beds:

Detail of the drainage holes in the drainage pipe at the base of the filter beds

The materials being prepared and brought from the next-door field (where the sand had been being washed) onto the site:

The lines we’d put into the cement plaster worked really well at letting the labourers know how high to fill each bed, and to make sure it was level.

The coarse layer goes in

The middle level gravel was sieved to get rid of all (most of) the dust in it – we were fighting against daylight here – the labourers stopped at 4pm, so we had an elite team of 3 or 4 doing the work after then.

At some point after 5, some more labourers turned up and the sand layers went in quite quickly.  The sand was thrown onto the sieve and raked over with a piece of wood, and the pebbles/ detritus discarded to one side.

Sieving the sand layers into the filter beds

Finally, we were done and scurried back to town for dinner and another layer of clothing – it gets cold when the sun goes down!