Responsible apartment communities segregate waste and reuse their water. Several residential communities have recently become more aware about sustainable practices of living. Yet there is quite a lot of catching up to do to practice sustainable living as a norm. In the third episode of the Neighborhoods Of Tomorrow – Interactive Webinar Series, Dr. Ananth Kodavasal of Ecotech Engineering gives the complete breakdown of the operation and maintenance of a community STP.
The Webinar Takeaways
Listing some of the takeways of the webinar held on May 16, 2020. You can click here to view the Presentation.
Five minutes of negligence by an STP operator can result in 3-4 days of outage. Therefore, it is necessary to ensure the in charge is well trained and always alert on their shifts. The pH, MLSS, sludge dewatering, recirculation, filter backwash are some of the things to monitor minutely.
The holistic way to approach the best practice for STP O&M, is to ensure absolute safety for operators and in charges. Proper PPE, LOTO Training to all in Waste Waster Treatment, good exhaust ventilation, proper illumination, proper safety handrails and efficient housekeeping of plants are not directly associated with the STP itself, but go a long way to increase its longevity and maintenance. The COVID pandemic does not change this requirement but rather refocuses attention on these safety protocols.
The Q&A Session
Q1 : How to manage STP for small residential communities (40-100 units)?
A : Micro STPs (80 KlD) can be used. Totally below ground and does not occupy extra space. The operations too are minimal and easy.
Q2 : Clarification on BOD as required by Pollution Control Board for Residential Communities.
A : Urban Reuse Quality Standards are the best to follow even though the requirements have been relaxed. To improve BOD and other parameters, regularly audit the STP plant, find out snags and address them. BOD 10, COD less than 50, residual chlorine more than 1 ppm – markers for perfect quality treated water.
Q3 : What is the cause and solution of discolouration of STP water and presence of worms?
A : Unlike Cauvery or Borewell water storage tanks, STP overhead storage tanks have to be cleaned once. A thorough monthly cleaning will help avoid both, the discolouration as well as presence of worms. It is also advisable to audit the plumbing engineering in such a case. Also note that treated water has a shelf life of not more than 24-36 hours.
Q4 : What are the legal responsibilities of a community on installing an STP?
A : Get the right design and functional specs from the correct person. That is the priority. The Pollution Control Board must issue an NOC and a Consent For Establishment. Also note, it is against the law to mix any freshwater in the STP.