Wednesday, January 24, 2018

Jakkur Lake Report

Authored by Shreyas Sati and Alana Helin as part of the BIOME Trust Wetlands & Lakes Project

Jakkur Lake is on approximately 160 acres and is located in the northern part of Bangalore to the right of NH44 near Yelahanka. The lake falls within Hebbal Valley as part of the Yellamallappa Chetty lake series in northern Bangalore. It is frequented by local residents who enjoy the provided walking path and kalyani. As of our visit on 28 November 2017, there was work being done to complete a walking path and plans for two citizen engagement/activity regions on either side of the lake. To the northwest of the lake, there is a BWSSB-operated 10 MLD STP which discharges an average of 7-8.5 ML into the lake each day. A constructed wetland covers approximately 7 acres in the northern part of the lake.

Overview and Observations
Jakkur Lake is located in Northern Bangalore.

Lake Area
160 acres
A 10 MLD STP is located on the northwest side of the lake outside the lake premises which typically discharges about 7 to 8.5 MLD of treated water into the lake. The STP was set up by BWSSB in 2004.

Jalposhan, a not-for-profit trust organization, has played an important role in rejuvenating the lake by organizing resources such as labour and finances and driving the work at Jakkur Lake by coordinating between various organizations and monitoring the progress of the work. While Jalposhan is presently an independent group, it originally was a part of a program under Sathya Foundation, a not-for-profit organisation which was involved in the conservation program at that time. Also, institutions such as ATREE and IISc have provided technical support in conducting studies on water quality and lake bed profiling. There are four primary inlets: three stormwater naalas and one where treated STP water enters the lake. Of the four inlets, two (Naala 2 and STP treated water) both enter the lake in the north. There are two outlets in the southern side of the lake.

There is a wetland in the north side of the lake into which the STP treated water (Inlet 2) and wastewater from naala 2 (Inlet 3) flows. After passing through the wetlands, the water flows into the lake through an opening in the bund.

On the western side of the lake, near the guarded entrance, there is a kalyani, boat jetty, and community centre building.

There is a 5.4 km walking path around the lake. There are specific sections of this walking path on either side of the lake which are frequented by locals to use the available amenities. Around the lake boundary, Jalposhan plans to create distinctive marked areas for various purposes. Part of the section of the lake perimeter will fall under the group’s conservation area where significant plantation has been done. There are also plans for a bird and butterfly habitat, a permaculture plot, toilets, children’s play area, community centre upgrades, and additional plantations in the coming months. We observed some algae buildup on the sides of the lake.

Fishing is done in Jakkur Lake through specific contractors. There are 3-4 fish species like Rohu, Catla, Jalebi, etc. that the fishermen breed into the lake.

The Lake
Four inlets were identified from which water would enter Jakkur Lake and are summarized below.
Naala 1 Overflow
Mix of storm and sewage flowing from Agrahara lake outlet enters from the east of the lake.

STP Treated Water
About 7-8.5 MLD of treated water and wastewater enters the lake through a wetland from the north of the lake.

Naala 2 Inflow
Mix of storm and sewage enters from the north of the lake.

Naala 3 Inflow
Presently, there is no inflow of wastewater from this inlet as that part of the drain opening into the lake was reportedly blocked by some chemical industry. We were also told that, prior to closing the drain, the overflow from Shivanahalli lake used to enter Jakkur Lake through this inlet.

Both of the lake outlets are overflow structures in the south of the lake. The two outlet naalas converge downstream and flow to Rachenahalli Lake.

Eastern overflow outlet from Jakkur Lake (near southern lake entrance)

Western overflow outlet from Jakkur Lake

A 10 MLD STP was set up by the BWSSB1,2 and constructed in 2004 just outside the lake premises . The STP uses an upflow anaerobic sludge blanket (UASB), a secondary level of treatment, for the treatment of sewage water. An average of 7-8.5 MLD of treated water is discharged into the wetland, which then flows into the main body of the lake.

Jalposhan would like to organise STP tours for interested people from point of view of education.

The Wetlands
There is a 7-acre constructed wetland in the north of Jakkur Lake, which has mostly been left to grow naturally. This wetland accounts for approximately 4.4% of the total lake area. There is a small area of water hyacinth growth at Inlet 1. At Inlets 2 and 3, there is natural growth of wetlands which includes water hyacinth, typhae, and alligator weed to name a few. Similar to Inlet 1, there is also water hyacinth growth at Inlet 4. Jalposhan is trying to create a self-sustaining model by way of allowing specific wetland species to grow, which at regular intervals can be harvested and sold to create additional income to the labourers. At this time, women from nearby communities who have formed a self help group (SHG) work at the lake every day doing a variety of tasks.   

Currently, there is one floating wetland in the main body of the lake which was not functioning at the time of our visit. However, there are plans to install floating wetlands at two inlets in the future. When planning these and other wetlands, the group is hoping to add to the existing diversity of plants - particularly as they search for alternatives to hyacinth such as lotus or lily plants.

At the time of our visit, our Jalposhan contact had expressed interest in creating a type of wetland maintenance plan which would allow the grasscutters, fisherman, and other stakeholders to agree upon and work under the same guidelines with regards to the harvesting of various plant species.

Contact Info
Jalposhan - Annapurna Kamat : 09731401881,  
ATREE - Veena Srinivasan :


1 comment:

Giridhar said...
This comment has been removed by the author.