Wednesday, August 30, 2017

Munnekolala Lake Report

Summary
Munnekolala Lake is on 15 acres 38 guntas land in Marathahalli and is located to the east of Bangalore behind Purva Riviera Apartment. It is frequented by many local residents who enjoy the provided walking path, kalyani and other amenities. On our visit (2 Aug 2017), we observed that there are no constructed wetlands nor an STP. In total, there are 5 inlet points and 1 outlet from the lake. All of the inlets will discharge untreated sewage and storm water into the lake only during flood events. The volume of inflow through the inlets could not be determined. The sewage from Naalas at two locations enter the diversion drain, which runs from the north of the lake along the eastern perimeter to the south from where the sewage flows into a sewer drain outside the lake area2. Note for map below - N: Naala, I: Inlet. Map labels match up with corresponding legend element. Top of map is north.


Overview and Observations
20170802_083032.jpg
Munnekolala Lake is located in Marathahalli, Bangalore.

Lake Area
15 acres 38 guntas
STP and Wetlands
None
It is reported that in 2013, the BBMP started its first phase restoration of lake for an estimated Rs. 2.7 crores which included desilting and construction of bund and pathway1. However, the bund here was not evidently visible. In its second phase, 1.15 Crores was spent on constructing of a pathway, planting of saplings, a Kalyani and park improvements. In the mornings and evenings, many local residents use the 1 km path around the lake and gazebos for walking, jogging, or other workouts.

One borewell was identified along the eastern side of the lake which appears to be used for gardening. There were also two towers, one of which holds an overhead tank (OHT) while the other is only a platform.

The Lake
There are two naalas from where the sewage enters into the diversion drain. Naala 1 enters from the northeast of the lake and Naala 2 enters from the northwest of the lake. Naala 1 also has an overflow structure which enters into the lake during flood events, whereas Naala 2 does not have any overflow structure. A total of five inlets from where water would enter Munnekolala Lake were identified and are summarized below.
Inlet (I)
Name
Description
Photos
1
Naala 1 Overflow
The combined water from Naala 1 and from the diversion drain from the Naala 2 would overflow into the lake during flood events. Currently, there is no overflow into the lake and all water flows into the diversion drain.
20170802_081535.jpg20170802_081557.jpg
2
Stormwater Overflow
Two culverts carry the storm water from the South West side of the lake into the lake bed only during a flood event. There is no sewage that will flow through these culverts into the lake through this inlet.
20170802_084537.jpg
3
Stormwater Diversion Drain Overflow
Storm water, during flood event, can overflow into the lake through a channel
20170802_080937.jpg
4
Stormwater Diversion Drain Overflow
Storm water, during flood event, can overflow into the lake through a channel
20170802_090048.jpg
5
Stormwater Diversion Drain Overflow
Storm water, during flood event, can overflow into the lake through a channel


The outlet from the lake is an overflow system under a bridge in the SE corner of the lake. The sewage from the diversion drain flows along the eastern perimeter of the lake and exits the lake at the south eastern side.

Around the edges of the lake, a buildup of algae on the surface was apparent. Along the walking path, there was a kalyani near the northern gazebo.

20170802_082243.jpg20170802_084545.jpg

The STP
There is no STP at Munnekolala Lake. Sewage is diverted from Naala 1 and 2 into a diversion culvert which connects to the main sewerage line outside of the lake.
It is observed that the sewage flowing through Naala 1 and 2 are generated by the apartments on the norther side of the lake. It was also stated by the authorities that the treated sewage from Purva Riviera Apartments is discharged into storm drains with permission from KSPCB. However, it still remains to be confirmed by the Apartment Association.

The Wetlands
There are no constructed wetlands at Munnekolala Lake. It is to be noted that there weren't any wetland plants even at the Naala 1 overflow which could have taken care of direct sewage inflow into the lake during a flood event.  

Contact Info
The lake is controlled by the BBMP while United Way of Bangalore (UWBe) and Northern Trust are now responsible for looking after the lake. The Munnekolala Lake Restoration Association (MLRA) worked with the BBMP during the restoration phase.

BBMP : Chief Engineer - B.V. Satish : stshbv@gmail.com : 9480683065, 25593060
UWBe : info@uwbengaluru.org
Northern Trust : +91-(80)-40178500

References


Saul Kere Report

Summary
Saul Kere sits on 61 acres of land in Kaikondrahalli, Bangalore just south of RMZ Ecospace and RMZ EcoWorld. An STP with a capacity of 100 KLD was under construction at the time of our visit on 3 July 2017. There are five sources of potential inflow into the lake, four of which would discharge untreated water into the lake during flood events, and one outflow from the lake. Unless there is flooding, the naalas will flow into a diversion drain and go around the lake to converge with any water that may leave through the lake outlet. Kaikondrahalli Lake drains into Saul Kere, which then flows north - possibly towards Bellandur. While there aren’t many extra amenities, there is a well-maintained walking path as well as a few benches around the lake. The wetland attracts many birds throughout the year. Note: In the map below, N - naala and I - Inlet as corresponding with the legend.


Overview and Observations
Saul Kere (Sowl Kere) is located in Kaikondrahalli, Bangalore and is approximately 61 acres. In 2016, commissioning of a new STP of 100 KLD began. There are five sources of potential inflow into the lake and one outflow from the lake.
20170630_111558.jpg

In the mornings and evenings, local residents use the 2 km path around the lake for walking and jogging. There are three BBMP gated entrances into the lake and one which is owned by Ecospace. There have been many improvements within the last year including new fencing in some areas, landscaping, and new overflow structures. Currently, there is no fence around the inner side of the walking path (between the path and lake) though there are large bushes that act as a barrier. Along the western side of the lake, there is a portion of built up land that includes a BBMP office for maintenance workers and the engineer to work from.

The Lake
We identified five distinct inlets where water would enter Saul Kere.

Inlet
Name
Descriptions
Pictures
1
Naala 1 Overflow
Discharges into NE corner of wetland
20170630_111055.jpg
20170630_111008.jpg
 (Bottom Left) - STP Influent inlet from NE corner. Influent flows left while overflow goes forward into discharge culvert as seen in the top right.
2
STP Treated Water
Discharges into wooded area in SE corner of lake

20170703_074950.jpg
STP effluent discharge point (center of photo)
3
Naala 2 Overflow
Not currently discharging, but would flow into SE corner of wooded area when flooded. Source is a mix of storm and sewage water.    
20170630_115539.jpg20170630_115548.jpg
(Top) - Naala 2 Overflow facing SE influent; (Bottom) - Facing lake
4
Naala 3 Overflow
Not currently discharging into lake, but would flow into wetland when flooded. Currently, water flows into a diversion drain that goes around the lake to Bellandur. Source is a mix of storm and sewage water.
(Top) - Influent drain facing south, currently flows to diversion drain; (Bottom) - SW Overflow Structure facing lake.20170630_114458.jpg20170630_114552.jpg
5
Naala 4 Overflow
Not currently discharging, but would flow directly into dry lake bed when flooded. Water may come from nearby apartments as well as upstream lakes such as Kaikondrahalli, Kudlu, and Kasavanahalli.
(Top) - Apartments and lake side; (Bottom) - View of West Overflow Structure facing the influent source.20170630_113838.jpg20170630_113802.jpg
As stated above, each of the overflow structures will allow untreated storm/sewage water to flow over the weir and into the lake during large rain events.

The only outflow from the lake is an overflow system under a bridge in the NW corner of the lake. This structure was built in 2016.
20170630_112202.jpg20170630_112155.jpg
(Left) - Exposed soil in front of outlet; (Right) - Outlet overflow structure.

20170630_112212.jpg
Saul Kere Lake view from outlet facing southeast.

There was no apparent build-up of algae on the lake edges. Along the walking path, there are three overhead tanks which were installed in early 2017. The plan is to for the tanks to be filled with lake water and used for gardening.

The plant growth around the lake is maintained by individuals who trim the grasses and perform other landscaping tasks.

The STP
The STP at Saul Kere was CSR funded and designed by Ecoparadigm. Construction began in 2016 and is currently being updated. The STP is capable of treating 100 KLD of sewage. The sewage enters the plant from the sewage drain (originating to the north) to the east of the STP and then the treated water is piped to the forested area of the lake. The source of the influent is from Naala 1. If flooding or high inflows occur, the water will bypass the STP and enter into the diversion drain that runs along the outside of the lake towards Bellandur.

It is an underground anaerobic baffle reactor and will eventually include a planted gravel filter and pond. Prior to the STP, that influent was discharged directly into the lake.

The Wetland
There are no engineered wetlands, however, the northern and eastern portions of the lake are a natural wetland. 20170703_080428.jpg
View of wetlands (taken from east side of lake facing west).

20170703_080835.jpg
View of wetland (from north side of lake facing south).

The wetland has a large number of plant species throughout the area and is home to a variety of fish and birds throughout the year. There were many migratory waterfowl and shorebirds as well as local species. According to a local resident, the number of birds will significantly increase when water levels are higher and fish are plentiful.

Contacts
The lake is controlled by the BBMP while United Way of Bangalore (UWBe), Genpact and Mapsas are now responsible for looking after the lake.

BBMP : Chief Engineer - B.V. Satish : stshbv@gmail.com : 9480683065, 25593060
UWBe : info@uwbengaluru.org
MAPSAS :  mapsas@googlegroups.com, mapsas.blr@gmail.com
Lake Supervisor - Dass : 9611923036, 9880757198



Monday, August 21, 2017

Citizen Lakes Dashboard update - May 26th, 2017

About this post

This is an update on the activities at Kaikondrahalli Lake, as part of the Citizen Lakes Dashboard project. In this trip to the lake, we installed a couple of instruments for measuring the lake height, which will, in conjunction with other data, be used for calculating the lake volume at any given time.

Overall Project Objective

The 3-year Citizen Lakes Dashboard Project (funded by Oracle) aims to make relevant lake data, using real-time sensors and citizen science on Bangalore's lakes accessible to citizens’ groups. Many of the lakes, as we know, are experiencing an increase in sewage and chemical waste dumping. An online dashboard will store the data and its inferences and allow visualization of important parameters that affect the health of the lakes. The findings will be communicated to key stakeholders and the wider community on a regular basis.


Progress so far

We are into the 2nd year and 5th month of this project. So far we have focused on 2 lakes - first Jakkur and then Kaikondrahalli (two more lakes will be added this year and one more next year). Various sensors have been installed at both lakes and data is being collected regularly. Using the data, a water balance has been worked out for Jakkur Lake. Nutrient analyses, of the inflows into Jakkur lake from the STP and the open drains, was completed. A remedial strategy has been proposed to restore the dissolved oxygen levels to arrest the eutrophication of the Jakkur Lake. Bathymetry analysis (the study of the lake bed) has been completed at both lakes.

The online dashboard has been set up but is currently being revamped based on stakeholder feedback. It will be made available for citizen engagement soon.


Partners

The partners in this project are ATREE (http://www.atree.org/), Biome Environmental Solutions (http://www.biome-solutions.com/) and Yuktix Technology (http://www.yuktix.com/). Many thanks to the lake trusts - MAPSAS (http://mapsas.org/) and Jala Poshan (https://sites.google.com/site/jalaposhantrust/) for helping facilitate this study at Kaikondrahalli Lake and Jakkur Lake respectively.

Prior posts

To get a continuity from the earlier posts, you can view the ones from March at

Part 1: https://biometrust.blogspot.com/2017/06/visit-to-kaikondrahalli-lake-for.html

Part 2: https://biometrust.blogspot.com/2017/06/visit-to-kaikondrahalli-lake-for_27.html





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This example illustrates how the Citizen Lakes dashboard can potentially play a key role in solving a lake's water quality problem.

In this example, the key quality parameters being sensed and measured are:
N: Nitrates
P: Phosphates
DO: Dissolved Oxygen


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The above picture shows the locations of all the sensors and the lake height measuring staff at Kaikondrahalli lake.


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This picture zooms into the location of these 2 instruments.

The next few pictures gives a photo-narrative of the installation of the lake height measuring sensor and staff.

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Sayan from ATREE has got several perforated pipes, which need to be joined together. The water level sensor will be put into this pipe.

We hired Mohan the plumber for the installation; he sent a couple of his men to do the job.

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The men join the pipe together


The perforated pipe now stands about 10 feet tall


The pipe is positioned at the desired location. The portion of the pipe below the water is only about 1.25 meters to the lake bed (on that day).

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The men use a coracle to access and affix the bottom part of the measuring staff and the perforated pipe to the vertical wall.

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The measuring staff is to the left and the pipe which will house the sensor to the right (while facing the wall)

Sayan has already lowered the sensor into the pipe and is calibrating it (correlating the readings with what aught be the correct values and adjusting the sensor output accordingly).

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After calibration Sayan puts back the sensor.

What you see here is the data logger portion of the sensor, which we will need to access on a regular basis to download the readings.

The sensing element is actually a wire that connects from this data logger and descends down the pipe to the lake bed, and is kept down at the bottom by a counterweight.

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Putting the cap on. Now the pipe is covered from the top, protecting the data logger from the weather elements.

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The installation work is at last completed!!

The distance from the measuring staff (on the left) to the bridge has been kept such that people walking on the bridge can make out the lake height reading.

We will be displaying a table from which a person can find the current volume of water in the entire lake, based on the height that they read on the measuring staff.

Pretty cool, yes?!! :-)

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A closer view of the 2 instruments

The water level sensor on the right will be logging the lake water height every 15 mins. This will allow a continuous set of readings over the year, which can be used for figuring out various useful inferences - like correlating the rainfall data (from met dept) with lake levels (from the sensor) and volumes (from bathymetry - will cover in another blog) - both during wet and dry seasons.


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Now heading on to the locations of the other 2 sensors - installed at the sewage inlets into the lake.




The sensor in this location was taken out earlier this year because it fell into the sewage and got damaged. We did not put in a replacement sensor because this location/installation structure was deemed somewhat inaccessible and unsafe.

We need to figure out a better installation which makes it more easily accessible - which will be covered in a subsequent blog!

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We now come to the second sewage inlet which has the level sensor installed since Feb 2017.

We observe that the pipe inside which the sensor wire element descends is blocked by debris. This would make the sensor reading incorrect.

Sayan gets ready with a stick to move the debris away from the pipe.

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The debris is cleared away.

We now come to the END of this photo-narrative. Stay tuned for the next update coming up fairly soon!


---Shankar Venkataraman---



 #tripszee #atree_org