Greywater system update

The greywater system is up and running. The water goes to the first tank and once the water crosses a point , the pump kicks in and pumps up the water to the filter cum tank . We had a very water intensive day today with a few loads of washing and kids in the bath but from what it appears we might have more water than what we need !! Next stage is to connect the water to the drip system .
Visually the water seems ok , no turbidity , a bit of soap coming through , a few days more till the biological filter or schmutzdecke kicks in.

The removal of contaminants in slow sand filters occurs mainly in the colmation layer or schmutzdecke - a biologically active layer consisting of algae, bacteria, diatoms and zooplankton. A ripening period of 6 - 8 weeks is required for this layer to form, during which time filter performance is sub-optimal.

From here
The amount of water makes me think that maybe we are underutilising the greywater system and should have integrated it with the flush water . But maybe I will just earn some 'brownie points' by offering to water my neighbours patch .

Greywater system

Today we finalised the greywater system that we are going to install . It is a very basic setup , greywater from the bath and the washing machine goes in a subterranean tank with a submersible pump which pumps it up to the terrace . The contractor is going to do the job of pumping up the terrace and I will make the rest of the filtration system which is essentially going to be a trench with gravel . The water will be released into a subsurface drip system . Schematically it is going to be like this .
If the water pump is 0.5 kw and takes even as much as half an hour everyday to pump up the water , the monthly consumption of electricity will be 15 Kwh which at 0.50 shekels/Kwh works out to 7.50 shekels a month or less than 2$ a month . The water saved will definitely offset the cost of running the pump .

Sewage - an exercise in futility

Every time you use the toilet you flush down from 10-15 liters of clean potable water which probably traveled many miles through a myriad network of holding tanks , pipes and what-not . And the act of flushing gets rid of the waste and all is forgotten to most of us . We all know that it goes down the sewage system but beyond that we don't care. I say we must because every pipe has two ends , flushing away your refuse just transfers it to the other end . So at the other end we create another system of settling tanks , aeration systems where this refuse is brought to a state where it is deemed harmless to be released into the waterways . The price is that the whole process is very energy and resource intensive . And it doesn't always work . Over time as the amount of sewage increases there is a need for more and more facilities or else as it happens all over the world , raw sewage is dumped into the waterways creating a serious health hazard . To illustrate

Take Delhi, as a typical instance. Yamuna is Delhi's main sewage drain. Yamuna enters Delhi at
Wazirabad - where the city draws its water supply - and after this an estimated 1,800 million
litres per day (mld) of untreated sewage flows through 18 drains into the river. In the last four
decades, the total sewage output has increased rapidly. Untreated sewage has grown even
faster. In 1999, the Central Pollution Control Board estimated that Delhi produces over 2,547
mld of sewage of which only 885 mld is collected through the sewage network for treatment
and the bulk - over 75 per cent flows into stormwater drains and then into the river. By late
2000, treated sewage had increased to 1,333 mld as had the quantity of sewage - still over 50
per cent of the city sewage was dumped into the river. By 2005, Delhi plans to triple its present
sewage treatment capacity at a cost of Rs 750 crore. But this will still be less than what is
needed. Paradoxical chase It is an ironic situation. Even if Delhi builds all the sewage treatment
plants, it will still not have the sewage to treat. Why? The city's sewage drains are choked and
silted. The government admits that the present capacity of the sewage treatment plants is not
being utilised and when it builds new treatment facilities, sewage never reaches these plants.
From Down to Earth

So we create a gargantuan system to get clean water , shit in it and then make an even larger system so that we get the shit out of it so that we can get clean water again . Sounds a bit crazy to me .

"Anyone starting out from scratch to plan a civilization would hardly have designed such a monster as our collective sewage system. Its existence gives additional point to the sometimes asked question, Is there any evidence of intelligent life on the planet Earth?"
G. R. Stewart

Wouldn't it be better to create a system where human refuse is handled at the source with minimal use of water , especially potable water when a really small fraction of the developing world has access to clean , potable water ? Wouldn't it be better to reuse the nutrients , give back the soil the nutrients that would otherwise be chemically synthesized ? I am talking Humanure but that is another story .

So how does my compost smell

Lately I have started inviting friends to smell my compost pile and the product . People have been quite sporting for the time being but clearly they do not share my enthusiasm for compost . There is a small danger of being left without friends if I keep up with it !!

To shower or have a bath

Today I figured that my two sons having a bath together used about 90 litres of water . A quick search on the internet put the average shower consumption for a gravity shower at 35 litres . It of course assumes an efficient shower head with water discharge of about 7l/min for a five minute shower. I was under the impression that baths take a lot more water but if two people take a bath together it is almost equal to a shower . The best part is that if you are using organic soaps you can even reuse the water . For collecting shower water you either need to have a separate system for your waste water or you have to stand in a bucket to have a shower . Now if all of us were to use the same water ..........

Waste 2

Composting organic waste has a number of advantages

• The amount of garbage is thrown out reduces considerably . On an average my garbage sack is half to one-thirds of wht it used to be .
• Lesser garbage means that the garbage trucks carry lesser garbage halfway across the country to a garbage dump . It could eventually reduce the number of pickups which can be a considerable saving in energy transporting and managing .
• Most organic garbage does not fully decompose in a garbage dump as there is too much of it competing for too little fresh air . Garbage in plastic bags is known to remain in its original state packed in nylon bags in a high methane surrounding for years on end. Even after the organic stuff breaks down there is no way of putting it to useful use as it is full of inorganic stuff of unknown antecedants . So organic matter in the garbage is effectively lost .
• Even if garbage is separated and taken to a composting facility it involves a lot of energy expended in separating and moving it .
• Organic matter goes back to where it belongs , into the soil to rise again like a phoenix as organic matter again .

Waste 1

Many years ago in my Urban Design days in SPA Delhi , I heard one of the most fascinating lectures on waste management . I don't remember the name of the person but he sure did kindle something deep down about urban waste . It has been on a low backburner all of this time till some time back , nothing drastic bjt a more concerted effort to deal with the waste we create .
The easiest part of it all is the organic waste from the kitchen and garden . All little scraps and pieces and waste go to my compost pile in the no man's land between the houses . Initially I was worried about the neighbors getting worried but one year down the line it doesn't seem to bother anyone and I have a constant supply of organic compost . Even gave some to our neighbor who showed some interest but then it was too much of a bother for him to separate the organic waste and walk 10 m up to the pile. So I continue with my solo crusade . To dispel some misconceptions

1. Compost does not smell if you take proper care to turn it once in a while and strike a good balance between greens and browns.
2. It does not attract rodents and the likes if one takes care to separate non-veg and dairy waste.

Besides

1. we have cut down our waste to a third .
2. we get nice black compost to grow our vegetables in .
3. the garbage collectors say a silent thank you every time they cross our house ( they should if they don't )