Pressure on PHE to provide clean water

SHILLONG: Mawphlang legislator SK Sunn has taken steps to ensure that there is clean water supplied to residents and directed the officers in this regard following the November 27 order of the High Court of Meghalaya on the water quality.
He carried out an inspection of the water works at Greater Shillong Water Supply Scheme (GSWSS) phases 1 and 2 at Mawphlang on Saturday.
A media team was also taken to the site for an on the spot assessment of the situation.
During inspection, Sunn said the clariflocculator (water clarifier) of the existing water treatment plant of 34.05 Millions of Liters Per Day (MLD) capacity, was designed during the late 1970s (GSWS project Phase I & II) and it was sanctioned in 1978 where the turbidity of Umiew river eater does not exceed 50 Nephelometric Turbidity Unit (NTU).
Sand mining
Since the 1990s, following sand and stone quarrying in the catchment of the river Umiew, the water has become highly turbid during the monsoon months and at times, touched a maximum of 1500 NTU resulting in over loading of the clariflocculator of the existing 34.05 MLD water treatment plant. As such, for flocculation to take place in the clariflocculator, coagulant dosage (alum solution) had to be increased.
Alum solution is used to purify water and remove turbidity.
In the November 27 order, the High Court had pointed about the high dose of alum solution which made water sticky and oily.
Sunn added that it was for this reason that the construction of additional clariflocculator, identical to size of the existing one, was planned under the contract with M/S Tantia Construction Ltd. Though the construction of the clariflocculator is in progress, the construction of a separate inlet stilling chamber, raw water channel, parshall flume, constant head chemical dosing tank and flash mixer separately for additional clariflocculator is yet to start.
So also, the construction of additional chemical house as envisaged in the contract is yet to begin.
Reduction of alum solution
The construction of the additional clariflocculator will reduce the load on the existing one by 50% and thereby it will facilitate flocculation to take place with comparatively decreased coagulant dosage (alum solution).
The contractor of Tantia Construction Ltd. taking up phase III works assured that they will complete the construction of the new clariflocculator, additional chemical house and the separate inlet works for additional clariflocculator before the next monsoon in 2019.
When asked, Sunn said as an elected MLA of Mawphlang constituency he felt that it was his responsibility to inspect the ongoing projects being implemented in the constituency, especially water supply project like GSWSS water works that provide water to the public in the wake of media reports and intervention of the court.