Utilize the input text as a context reference, choose the right relationship between 'water treatment' and 'water' from the options.
Options: product/material produced, business division, operator, platform

It boasts of a sewage treatment plant of 600 KLD, which is based on environment-friendly extended aeration technology, water treatment plant, rain water harvesting and re-use of treated water for flushing and gardening.
product/material produced