Situated in the northern part of Bangalore, the Hebbal Lake is one of the oldest and most popular lakes in Bangalore. The lake is predominantly eutrophic due to the inflow of sewage.
Eutrophication is the ecosystem’s response to the addition of artificial or natural nutrients, mainly phosphates, through detergents, fertilisers, or sewage, to an aquatic system. It typically leads to hypoxia i.e. depletion in the level of oxygen in the aquatic body.
The target area for this project is the problem echoed by eutrophication, that is the amount of nutrients in the lake. The problem here is the excess availability of them in the lake, causing the water quality to deplete, further deteriorating the quality of the lake.
Systems Map 1: Regular visitors within the course of 3 days at Hebbal Lake Park
Due to number of industries surrounding it, the Hebbal Lake receives a huge amount of industrial waste that add to the chemical composition of the lake, causing an imbalance. This is mainly a huge amount of Phosphorus in the lake which is also caused from land run offs and detergents. Here is the impact of this chemical on the Kere.
Systems Map 2: Listing waste generators in and around the Hebbal Lake, and their impact.
Aquaponics is a self sustaining ecosystem which combines aquaculture (raring fish) and hydroponics (cultivating plants in water). The by-products of the fish along with the nutrients of the lake are absorbed by the plants, circulating clean water back to the body.
As a design intervention, I am shaping a system that controls the amount of nutrients in the lake. The lake has high concentration of phosphorus and nitrogen, both of which are vital for plant growth. Taking this to my advantage, I am proposing an Aquaponics system that could benefit the farmers in crop and plant growth and in turn keep the water of the lake clear of its excess nutrients. This Aquaponics System will be viewed as a learning and participatory space for the visitors of the lake, who can come and observe how these nutrients effect the lake, along with the science and labor that goes about into the aquaponics system and the farming activities.
The functioning of the Aquaponics System:
1. The water from the lake is pumped out using Pressure Tank Water Pump into the water reservoir. Here the water remains stagnant for a day because of which excess sediments settle on the gravel bed, purifying the water.
2. On reaching a certain point, the water from the reservoir starts flowing into the Grow Bed through the pipe channel created around.
3. The pipes end with a water outlet that has many holes through which the water seeps into the bed and is absorbed by the plants.
4. Once the nutrients are absorbed, the water begins to flow out through the holes present at the bed, thus returning a purified form to the lake.
Aquaponics System for the Hebbal Lake, Bangalore
The internal plumbing of the system
