The new enclosure with its bear pool is ready for its May opening.

Part of the water filter system providing recycled water.

The final, clean water is stored in above-ground tanks.

Vietnam Director Tuan, and Operations Manager Robert test the new water supply.

Because of our wastewater treatment system, these pools are not just great fun – they’re environmentally friendly as well. The water used in the swimming pools is recycled wastewater (sewage – from both humans and bears).

Our simple, yet advanced system purifies the wastewater to the point that it is safe for humans to drink!

It also means that the river running through the park and our centre is protected, with no drain on its resource so its levels can be maintained, and there is no run-off from the centre risking its contamination. Protecting the river is of great importance to us given the speed at which Vietnam's rivers are succumbing to pollution and despoilment.

As we are located in Tam Dao National Park, north of Hanoi and 1.2kms into the park itself in what is termed the “buffer zone”, we are not on the main supply of either electricity, water or sewage (wastewater). The water supply to our facility comes entirely from the small river which flows about 10kms from Tam Dao Town up in the hills, and passes our station and on into a lake 4kms downstream.

Our initial treatment is to get the river water quality to a level where bears can drink and humans can wash with as little impact on the river as possible. This is done by a Backwashing Micro-z filter and Ultra-violet filter treatment system.

Then there’s the wastewater. Wastewater from both bears and humans is treated by a natural biological, low-maintenance process, using a combination of modules.

We are using the basic four modules:

• Primary treatment – sedimentation and settler tank
• Secondary treatment – in two large bio-digesters
• Tertiary aerobic treatment – in sub-surface flow filters
• Tertiary aerobic treatment – in a planted gravel filter or polishing pond

At this point, the treated water still contains many contaminates. We do not want to use chemicals so have avoided adding chlorine to the final freshwater tank and instead, have arrived at our tailor-made treatment system.

We are using a four-treatment process, again with no chemicals, which delivers good quality water clean enough to use for the double bear house swimming pools.

The four treatments are:

• Activated carbon backwash filter to remove smell, colour and sediment
• Ion exchanger to remove ammonium – this is the same as a water softener, but with different filter media
• Ultra-filter to remove turbidity, e-coli and coliform
• Ozone generator to remove ammonium, smell, colour, viruses, BOD and COD

This treatment system can supply 1 cubic metre of water per hour to the double bear house.

To finish off the process, we have added a fifth filter – Reverse Osmosis – and this is the final step in getting the water to a level of quality to deliver it straight to the faucet for drinking.

We are very excited to be using this unique system to convert wastewater into potable drinking water, and at the same time, contributing to the conservation of Vietnam’s ecosystem. This innovative model preserves the surrounding environment by totally eliminating the need for waste disposal.

We are now trying to raise funds for the second eco-friendly wastewater system we need to install to cope with the further expansion of the rescue centre. While it may be costly in terms of initial outlay, in the long term it is a small price to pay to preserve the environment we inhabit in this beautiful park.

Donors who sponsor this or the development of any other part of the centre, have the opportunity to name or dedicate their sponsored item after themselves, their organisation or their friends. These dedications will be displayed onsite as a lasting tribute to those named.

You can download a full report on how this treatment system works, along with details on cost and construction phases here.