Sewage system and water crisis in Indian cities

The other day I was traveling through city of Bengaluru by BMTC bus, suddenly I happen to see a big channel beside, parallel to the road. Initially I thought it’s just a water passage or something. After getting down I went to check it, yes it was a water stream but a stinky one. Yes it was a sewage water channel. And I even saw a heap of plastic in it, which was not only filthy looking but it was looking like a growing devil which had potential to choke the entire passage. Suddenly a thought struck me while major cities including Bengaluru are facing acute water crisis, why are we wasting huge amount of water mixed with sewage and let it flow into our valuable water bodies(lakes, ponds and even to river)?

Instead cant we reuse this generated gray water to clean up our vehicles or may be to feed our garden?

Sounds simple right? But it is not, this simple matter has made a so much ruckus in the city.

After going back to home 'curious me' went to search about these huge sewages around the city. As expected I came to know so many astonishing facts about our poor sewage/water management.

Here I have tried to put those facts and ways of better management of it below.

Water source to Bengaluru: The capital city Bangalore nicknamed as garden city.

It actually had gardens and city full of lakes. Before urbanization of the city it had more than 500 lakes. As the city started filling up with buildings; the industries started budding and ultimately the farms, gardens and lakes started to vanish. Well unfortunately the city is not longer a garden city anymore.

 In early 90s the Bangalore had more than 500 lakes. Those were potential sources of water of people. Now most of the lakes have either drained or filled to build the city, and the count it has gone down to only 17 good lakes (https://en.wikipedia.org/wiki/Lakes_in_Bangalore)

. Once with self sufficient lakes and ground water level the city was independent for its water supplies. But now it mainly takes water from Kaury River which is approximately 100 km s away from the city and urgent needs are fulfilled by sucking up the leftover ground water.

80 percent of this used water being converted as sewage and only 40 percent of the it is treated. Bangalore in total generates approximately 1400 MLD (million liters a day) of sewage a day if its 60 percent is untreated then the number would be 840 MLD well that is a huge number and more dangerously all of these untreated water, including chemicals from industries are contaminating our water bodies every single day. This number for whole Karnataka state is 2500 MLD.

This contamination is not only making the water sources inaccessible it is also contributing contamination of ground water surrounding city. In fact this whole process is one of the contributors towards city’s water crisis. This year Bangalore city was about to hit acute water crisis and in 2022 city is expected to witness zero day.

As we are near to the line of limit I strongly believe this is the high time to address this problem with higher priority. This is not only a story of Bangalore, over 21 major cities of our country including Bangalore are expected witness worst water crisis of all time in 2022 according to data. If we consider quality level of available water, it is not really drinkable state. Facts shows us, India is in 120^th position in 122 countries as per as the water index is concerned.

Question for you, isn’t it a freaking factor that we are not actually recognizing it? Cant we come to a common solution by treating sewage and reusing it?

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zero day is a term used in cape town south Africa to explain zero ground water level and apocalyptic stress among citizen of it.

This very same situation is expected to occur in 21 major cities including Delhi, Bengaluru and Chennai.

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Where does the sewage come from and go? is it a serious issue?

The sewage mainly consists of used water mainly domestically. If the sewage used is in the kitchen and washbasin, obviously, it will have less of suspended partial and it will be less polluted, such type of water is called as gray water.  The gray water will have larger scope of reuse with less efforts in treating it.  But only problem is that we don’t have proper STPs at societal level. And hence it is mixed with other sewage and it goes untreated.

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BASICS OF SEWAGE TREATMENT (IN INDIA):

Sewage is basically used water with suspended waste materials in it. To make the sewage completely reusable we have to treat it in three stages those are primary, secondary and tertiary. In primary treatments the floating debris and floating materials are removed with meshed and other filters and this allowed for sedimentation of some waste materials. This makes a consistent watery  feed for secondary treatment where anaerobic microorganisms are added which helps in digesting organic materials in the waste water. This microorganisms are later removed with addition of chlorine to the water. This secondary treated water is  now eligible for non-potable purposes like toilet-flushing and gardening.

Tertiary treatment involves more advanced processes like reverse osmosis (RO) and de-mineralisation. Dissolved solids and nutrients get further removed during these processes. Depending on the grade of tertiary treatment, recycled water can be used for drinking, as coolant in industries, or in precision industries like electronics.

 

The most common sewage treatment method used in India is Activated Sludge Process (ASP), which had been invented in England over a century ago. ASP mainly reduces BOD (Biochemical Oxygen Demand), fecal coli-form level, turbidity etc. Extended Aeration, Sequential Batch Reactor (SBR) and Up-flow Anaerobic Sludge Blanket Reactor (UASB) are some other conventional treatment technologies. These are mostly variations of ASP itself.

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As above mentioned in Bangaluru generates total of 1400 million liters of sewage every day and 60 percentage of it is untreated. This untreated water eventually gets drains out in lakes, rivers and other water bodies around the city. Main of such water bodies are Vrasabavati river(AKA Kengeri Mori), Ballandur lake and Varthur lakes which are well known for the hazards which we have created and high pollution levels of it. In past these water bodies have also made into headlines because of fire incidents(by bio gas generated in it) and clouds and foam formation and death of floura and founa around it.

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Currently, Bangalore generates 1400 MLD wastewater, as per BWSSB’s conservative estimates. The city has total treatment capacity of 721 MLD, but only 520 MLD gets treated on average. Here is a map of the existing and proposed STPs by BWSSB/BBMP in Bangalore.

Below is a list of existing STPs operating in the city:

Plant	Capacity in MLD
Vrishabhavathi Valley	180
K & C Valley	248
Hebbal Valley	60
Madivala	04
Kempambudhi	01
Yelahanka	10
Mylasandra	75
Nagasandra	20
Jakkur	10
K. R. Puram	20
Kadabeesanahalli	50
Rajacanal	40
Cubbon Park	1.5
Lalbagh	1.5

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Every year we see videos of froth filled Bellandur lake flashing in the news. You also must have seen incidents of lake water catching fire. People/residents surrounding lake goes to strike, it hardly affects government, BBMP or local corporator for that matter. The fact is that we do not have enough STPs around the city those are there are not effective enough to handle the flood of sewage. We all see the today's state of the river Vrshabavati, we it is known as Kengeri Mori.

How can we solve it together?

1)Government is being ignorant that is Crystal clear. Now it is left to us, we have to work together and set up small secondary STP s at societal levels such that we can reuse the water in non portable forms such as gardening and flushes. This problem was earlier tried to solve and addressed to. it was also made a law to set up mini STPs in societies and apartments, but people started to retaliate by calling strikes to oppose it. After seeing this one thing is clear that the problem is not only a economical problem it’s a social+economical problem.

 It is not only an economical problem it is a socio-economical problem.

2)Gray water and its cleaning:

Having small filters, STPs built in at house level and atleast treating the water in primary level will have its own benefits.

3)Bringing behavioral change: 

As it is socio-economical problem, Bringing behavioral change in the society by star campaigners, celebs and politicians will have impact. As saving lakes and sewage as important as other problems its just underrated. AND giving proper awareness and educating people is much needed.

4)Floating treatment wetlands (FTW) and other modern techniques will help to solve it. state governments can collaborate or seek suggestions from other state, if they are doing progressively good work.

5)Working together: As most of our city's problems are not yet solved by miscommunication and lack of cooperation between different government organizations, working on problems closely and together will definitely give solution to it. 

6)Planting, Rain water harvesting and less water usage are conventional methods by which the water can be conserved and used to recharge the groundwater level. 

Chennai is first one to make a mandatory law for rainwater harvesting but its has not been implemented properly.

Bottom-line:

The fact is: we all know that, It is a haunting problem like every other environmental problems. It is a high time to address it but unfortunately the government and citizen are being ignorant about the severity.

references:

http://bengaluru.urbanwaters.in/wastewater-treatment-and-reuse-49

https://timesofindia.indiatimes.com/city/bengaluru/chatbot-that-unites-artists/articleshow/69285257.cms  vrsabavati

All about screening process in SSB

We all know whole SSB selection process is conducted in two stages followed by medical examination. In this blog lets understand why stage 1 is conducted; what all are conducted in stage-1; as stage 1 is also called as screening you can expect the words to be used alternatively. 

Why stage-1/screening?

Screening is the process of filtering started in late 90s. It is done only with a purpose of filtering down the reportees number to the capacity of the stay at the centers. It is also done to gauze the competence of the candidate. after all there is no point in testing an incompetent candidate. 

What does screening(stage -1) in SSB consists of?

The screening process in the SSB consists of two tests in it. One, OIR(officers intelligence rating), second, PPDT(picture perception and discussion test)

OIR(Officer's Intelligence Rating): 

This is a basic intelligence test consisting of two sets of papers namely verbal and non-verbal. number of questions may vary from 30 to 50 in each set and the time is kept accordingly. in general you will get 30 sec. to solve each question. As the level of questions are fairly easy anyone with average IQ and fair practice can solve all the questions. Before the test, interviewer/invigilator will explain the type of questions, mode of answers etc. so do not worry much. Pay attention and exercise your logical brain before hand with daily practice.

From where can I prepare for OIR?

Well for SSB OIR, Indiabix is the right place to practice online.

Some books: R.S.Agarwal, OIR e-books from SSBCRACK, AFCAT books from Arihant

What are they testing by OIR? 

OIR is just a test of basic intelligence. By OIR they are testing how fast one can solve logical problems.

As there are no negative marks try to answer as many as you can; If you are unable to answer certain questions guess it. It is essential to score at-least 80% in the OIR to be in safer side.

PP&DT (Picture Perception and Discussion Test):

In this test basically a picture is shown for 30 secs., you will have to write a story around the picture and discuss with the group of 10 to 20 candidates and come to a common consensus. details of the conduct are given below.

1)All the candidates are made to sit in the testing hall; and given with instructions.

2)Answer sheet will be distributed and a black and white picture will be shown for 30 secs. The show picture will be deliberately blur.

 

3)One minute will be given to note down the characters and to write the action of the story.(you can see this in sample paper given below)

4)Then approximately 4 minutes will be given to write the story. the part of instruction given for the story writing is;

"write a story of 70 to 100 words; let free your thoughts; keep in mind to express the feeling, emotions and thoughts as free as possible without paying attention to the beauty of the expression; The story should contain what lead to to the situation, what is currently happening what is most likely outcome";

Some facts while writing the story on answer sheet given: 

In the answer sheet given, there will be a rectangular box given in the top corner of left hand side. there you need to encircle the spot of the character which you have seen first; inside the circle you are suppose to mark the gender of the character( M- male, F-female, P-person/gender cant be determined), age of that character and mood of the character. If you see more than one characters mark them with dot or cross. You are also expected to write the action visible in the picture. For better understanding, go to sample sheet given at the end of the blog.

5)after writing down the story the sheets will be collected back; and generally there will be break of 15 to 30 minutes before the discussion; (you will be advised not to discuss the story among others)

6) Now the discussion part; for discussion candidates are split in to group of 10 to 20 (based on number of reportees) and made to sit in semicircular fashion according to chest numbers.

7)After candidates are made to sit in-front of assessors general instructions will be given. This part of test consists of two sub-parts story narration and discussion; 

Story narration: candidates have to narrate their story in crisp, one after other within 1 minute.

Discussion: Once the last person finishes the narration; the discussion to form common story starts. I am re-stating  Once the last person finishes the narration; immediately the discussion to form common story starts.

Note: be ready for heated discussion.

The three assessors sitting, will be 1)GTO(group testing officer), 2)IO(interviewing officer), 3)Psychologist. The maximum chunk of the evaluation will be done while narration, while narration Psyc. officer will judge format of the story( he checks, is the story practical/sensible). while IO check the way candidate narrated the story( he check has the candidate narrated the story confidently, is the story understandable, is the English/ language used is fair). While GTO tests the group behavior during discussion.

A sample picture and story is given below:  

SAMPLE OF ANSWER SHEET