By Our Reporter
SHILLONG, Oct 5: After facing embarrassment over a lab report confirming that 44 out of 46 water samples, collected from 46 localities of Shillong, were found to be unsafe for drinking, the office of the Chief Engineer PHE on Thursday said strict instructions have been issued to the Superintending Engineers specifically responsible for supply of water to the Greater Shillong Agglomeration area for strict quality maintenance and monitoring and subsequent remedial measures, if the need arises.
The PHED said water supply to the different parts of Shillong is being supplied and maintained by the department, the Shillong Municipal Board and in some areas by the local Dorbars.
Breaking down the supply chain to the various localities, it stated that the main source of water supply to Shillong is from Greater Shillong Water Supply Scheme which draws water from the impounding dam constructed across the river Umiew at Mawphlang.
Informing that there except for stone and sand quarrying there are no coal mining activities in the entire Umiew river catchment, it stated that the pH value of Umiew river water, in most cases, is above the minimum permissible limit and the river is highly turbid especially during the monsoons due to sand and stone quarrying.
“Water samples are also regularly collected at equal intervals from different reservoirs of the Scheme including me store reservoir of GSWSS located at Mawphlang 4th Mile reservoir at Upper Shillong for testing at Meghalaya State Pollution Control Board (MSPCB), Shillong, and NABL Accredited PHE District Laboratory East Khasi Hills Shillong,” it stated.
Stating that the results of the tests by MSPCB and PHE Laboratory indicated that the parameters of treated water supplied by PHED from GSWSS are within the permissible limit of Drinking Water Standards and therefore potable and fit for consumption, it stated that the pH value in content, total coliform count, turbidity of water being supplied from GSWSS so – are well within the limn of drinking water standards and in no case non-potable water was supplied to the public
“ However, water at the consumer end may be turbid especially during the rainy season which is most likely due to leakages in the pipelines/and the current shifting of the Gravity Main pipeline of GSWSS from Mawphlang towards Shillong due to construction and widening of National Highway from Shillong to Tamabil,” it clarified.
It also clarified the concerns on bacteriological contamination of water and stated, “With regards to bacteriological contamination of water, this may occur due to various reasons like leakages in the distribution pipelines, cross contamination from other sources, improper collection of water sample etc., hence bacteriological contamination of the sample cannot be ruled out.”
It mentioned that water sample from GSWSS tested in the PHED Laboratory with respect to iron contamination is well within the permissible limit as per the Amendment No.1 June 2015 to IS 10500:2012 Drinking Water-Specification (Second Revision). The tests method followed by the PHED laboratories for estimation of iron is as per IS3025 part 53 2003 (Reaffirmed year 2019).
The department also asserted that there are specified procedural steps that are required to be followed in collecting water sample for analyzing in laboratory for different parameters of water PHE reservoir complexes located at 4th Mile Upper Shillong and other reservoirs under GSWSS at various locations are restricted areas, for obvious reasons.
“No permission had been sought for, nor any were given by the Chief Engineer, PHE, during the month of August 2023 for allowing any agency and/or individuals to collect water sample for Laboratory Testing,” it stated.
Referring to the report, it said, “As per the report it may be noted that water samples were collected from different parts of Shillong Municipal area and its adjoining localities and water supply to these areas are made by PHED, SMB and some areas by the Local Durbar Under Municipal Areas, water is supplied to the Public through Municipal service tanks where water from 7 (seven) municipal sources is also supplied together with the GSWSS water.”
“With regards to water supply to other localities outside Municipal areas, water is being supplied through GSWSS or other PHE/Local Durbar service reservoir from the PHED or Local sources as mentioned,” it added.
It further added, “In view of the above report, the department is all geared up to cross check and take up remedial measures wherever necessary, if and when required.”