BCU School Kitchen Garden Grey Water System
Recently we worked very intensively establishing the grey water system at the BCU School Kitchen Garden, part of the overall strategic design plan for the site. Initially the grey water outlet was unsightly and unhygienic, as the water runs from the very busy school kitchen which caters for over 150 people per day, so it was a priority to establish the system properly and as quickly as possible.
Site of the grey water system before work began.
The grey water from the BCU school kitchen which caters for the whole school, utilises 4 different filtration ponds across two different grey water outlets from the kitchen to clean and purify the water.
The first pond system development:
Leveling the first pond
Bamboo reinforcement for first pond. All bamboo had to be sourced and harvested by hand by our team.
Threading the bamboo to make frame
First ponds basic frame
Rendering the pond with cement
Finally taking shape
Laying the paving from recycled pavers over the grey water piping to ensure the safety of the pathway
Finishing the pathway in between the pond systems
BCU school students and friends planting in the pond on earth day
The second filtration ponds
Kitchen water waste would run direct from the kitchen sink into these two ponds
The first stage is the taller pond, and then the shorter pond.
The BCU school head master, Pak Gunarjo and school foundation chairwoman, Utami Geiger plant into the pond on earth day
This pond is layered with coconut fibre, charcoal, compost, worms, sand, gravel, to help purify the water which then run into the third and final pond systems.
The third and final pond systems
The first and second stage ponds run into the crescent shaped pond for further purification. When undertaking a task, we always utilizing available materials around us, trying to recycle as much as possible and at this stage we created ‘eco bricks’- plastic water bottle rubbish filled with rubble. These eco-bricks then were built into the pond wall for reinforcement.
Rubbish discarded plastic bottle reinvented into ‘eco-bricks’ for the pond wall reinforcement.
We also utilized glass syrup bottles that had been dumped into the pond frame aswell.
Discarded glass syrup bottles reclaimed and used in the pond wall frame
It took alot of work and was a real team effort with some working into the night to finish it.
Recycled pavers were also built into the pond wall frame.
And the whole pond structure was reinforced with wire mesh, cement rendered and the was sealed with a waterproof pond sealer.
The first and second ponds would flow into the crescent shaped pond which contained various layer filters including charcoal, various river rocks and worms. This crescent pond wold overflow into the final round pond, with there overflow from this pond flowing into the yet to be cultivated school kitchen garden.
Orangutan from the ‘Penjelajahan Orangutan’ performance appears at the grey water system on earth day..!!
As part of earth day celebration, we planted a number of plants in all the pond systems to contribute to and finalise the link in the purification process of the grey water. This included planting reeds, bamboo and various water plants to help further clean and bring the grey water to optimum levels.
SKG Grey water system was finished late April 2017 and took an intensive 1.5months to complete. The final grey water output had been purified to a Ph level of 7 which is ideal for aquaculture and as such fish and turtles have been introduced to the system.
This grey water system is not just about pollution control and managing our waste, but in the spirit of the school kitchen garden concept, it has been created to be used as an outdoor classroom, providing a unique opportunity for the whole school and broader community to learn about pollution control, water management and maintaining ecosystems.