Monday, June 24, 2019

Varthur Lake Wetland Workshop

Sensing Local along with Biome Environmental Trust, Whitefield Rising and Varthur Rising organised a public participatory planning workshop to develop a Wetland for Varthur Lake as part of its rejuvenation project on 5th January, 2019.  Various stakeholders were brought together to discuss and arrive at an appropriate guidelines for designing the Varthur Lake Wetland

                        

A link to a report of the event -  in the Hindu

Friday, June 21, 2019

In-Stream Decontamination System at Saul Kere

In-Stream Decontamination system is a small-scale collaborative project constructed near the southern inlet of Sowl Kere.  This intervention is part of an ongoing collaboration which includes diverse partners spanning Design, Engineering, Civil Society, and Science perspectives. The six-fold partnership includes input from Biome Environmental Trust (project management, collaboration, coordination), MAPSAS (community engagement), Eco Paradigm (engineering & construction), Commonstudio (design), ATREE (monitoring), and Wipro (fiscal sponsorship).  

This small scale intervention “model Nallah”, approximately 2M Wide and 8M long has been constructed next to the STP at Saul Kere.
                      
Within this space, we will run a series of experiments with jelly stones and terracotta rubble metarials. The first treatment will test the removal of organic contaminants by means of jelly and Terracotta rubble material. Terracotta has properties which makes it a viable biofilter media for urban wastewater. We plan to test the system for flows between 2.4 and 9.6 KLD.


      

The ultimate aim is to use the insights of the Sowl Kere studies to develop a series of larger interventions which can be placed directly within nallahs to prevent the contamination and eutrophication of urban lakes. We call this larger approach “Strategic In-stream Systems” or “STRAINS”— decentralized, frugal, flexible, and inclusive.

Sunday, June 16, 2019

Biodiversity Walk at Rachenahalli Lake


After an excellent walk at Jakkur our next walk was at Rachenahalli on the 9th June 2019 as part of the Citizen Science and Lakes initiative.  About 25 people joined us for the walk of which 15 were children. Aswathy led the walk and started with the tree we were standing under, The Jamican Cherry tree also called Singapore cherry or Kaskase tree.  She spoke about how the small birds love the berries of this tree and that the red berries are very sweet and can be consumed by humans too.
                              
Under the Singapore Cherry tree

Further we came across Black Babul tree or the Karijali tree

                               
Black Babul or the Karijali tree

and  the Sacred fig tree.  

 
                                                        Sacred fig or The People Tree


Fig fruit

For more information on the ficus and the Black Babul tree please refer to our Biodiversity walk at Jakkur lake   


As we moved towards the Wetlands area children got to observe the behaviour of Purple moorhen which was hopping on the wetland reeds.  Purple moorhens nest and roost in the wetlands.

                         
                                       Children observing purple moorhen in the wetland


                                                                Purple moorhen


As we were observing the moorhens a plant in front of us had these strange leaves.  These are leaf gall an abnormal growth of the leaves caused by insects. Different insect creates different shaped galls. These are not harmful to the plants/trees

                         
                                                                  Galls on the leaves


Children were fascinated to observe Indian Shag or Indian Cormorant. It diving into the water to catch fish and then surfacing out, sitting on a nearby stump and drying its wings.

                           
Indian Cormorant drying its wings

The walk ended at the gazebo with children seeing some pictures of butterflies. They tried to identify the butterflies that they have seen.





Wednesday, June 12, 2019

Testing for Lake Water Quality: What are the parameters that we should check for

If you are trying to rejuvenate a lake and want to know more about what parameters to test for, you can use this blog as a reference. Lakes in Bangalore are often polluted with sewage inflows, industrial effluents and catchment runoffs. To better understand the water quality of the lake is, we have created 4 categories
(A) The basic parameters
(B) Industrial effluents
(C) Pesticides
(D) Testing for the first time

(A) The basic parameters that need to be tested for in a lake area:
  1. pH
  2. BOD
  3. DO
  4. TDS
  5. TSS
  6. Nitrates
  7. Phosphates
  8. Total Coliform Bacteria
  9. Free Ammonia
(B) If industrial effluents are being discharged into the lake, the additional parameters that need to be tested for are listed below. The general standards for discharge of effluents, can be accessed through the following link: http://cpcb.nic.in/industry-effluent-standards/
  1. Arsenic
  2. Cadmium
  3. Mercury
  4. Zinc
  5. Chromium
  6. Lead
  7. Nickel
  8. Iron
  9. Copper
(C) If there is possible contamination from pesticides, the additional parameters that need to be tested for are:
  1. Alpha BHC
  2. Beta BHC
  3. Gamma BHC
  4. OP-DDT
  5. PP-DDT
  6. Alpha Endosulphan
  7. Beta Endosulphan
  8. Aldrin
  9. Dieldrin
  10. 2,4-D
  11. Carbonyl
  12. Malathion
  13. Methyl Parathion
  14. Anilophos
  15. Chloropyriphos
(D) If you are testing the water quality for the first time 
We recommend doing a complete potability test according to the drinking water standards set by the Bureau of Indian Standards (BIS 10500) It can be accessed through the following link: http://cgwb.gov.in/Documents/WQ-standards.pdf

Testing Labs in Bangalore

The cost for water quality testing could vary anywhere from Rs 1,500 to Rs 15,000 depending on the parameters being tested. For more accurate information contact a water quality testing lab and mention you want to test lake water quality, they will send you the list of parameters that they can test in their lab and the respective quotation. Listed below are some of the testing labs in Bangalore along with its links and contact information.


Lab Name
Location
Contact Information
New BEL road
98441 68829
Whitefield
74114 39839
JP Nagar
080 2658 9777
Mahadevpura
96869 77009
Rajajinagar
080 2350 2684
Kempegowda Layout
91523 22165
Laggere
95388 88098
Rajajinagar
080- 23356415
Peenya
080- 2839 2230

Surface Water Quality Standards

Testing the above mentioned parameters will tell you what the quality of the lake water is but to know what standard it needs to meet depends on the end use of the water. The Central Pollution Control Board (CPCB) of India defines water quality from the users point of view as ‘the physical, biological and chemical characteristics of water by which the user evaluates the acceptability of water’. Based on the primary water quality criteria CPCB has classified surface water into 5 classes (based on the expected end use), as shown below in Image 1.

 
Image 1: Classes of Surface Water

To use the lake water as a source of drinking water it needs to meet Class A or C standards, similarly to use the lake water for propagation of wildlife and fisheries it needs to meet Class D standards. As per data collected by the Karnataka State Pollution Control Board, most lakes in Bangalore are classified as D or E. To know more about the different standards as per IS-2296 refer to Table 9.1 in the following link https://elibrarywcl.files.wordpress.com/2015/02/surface-water-quality-standards-as-per-is-2296.pdf


References:


Lakes Water Samples Classification by the Karnataka State Pollution Control Board


Water quality parameters and the importance of each
https://www.epa.ie/pubs/advice/water/quality/Water_Quality.pdf

Tuesday, June 11, 2019

Video on Seepage Management at Safina Towers

Safina Towers located on Ali Asker Road, had been facing seepage problems in their lower basement since the building had been constructed. The volume of water seepage reached an alarming amount during the heavy monsoon rains of September, 2017 which is when Mr. Madhiazhagan, the Maintenance Head of Safina Towers, reached out to Biome.

Safina Towers implemented Biome's recommendation of digging three open wells within the property, one near the eastern boundary, one near the northern boundary and the other near the southern boundary. Almost a year later in October 2018, Mr. Madhiazhagan informed Biome that their basement was free from water seepage and that they were able to pull out 1 lakh liters of water every day for their personal consumption.

This project shows the beneficial effects of open wells- it helps recharge ground water, and also reduces flooding and seepage. Click this link to watch a short video on seepage management at Safina Towers.
Aerial view of Safina Towers