Now, Ponda and Tiswadi receive turbid tap water

PONDA: Twenty-five days after facing a severe water shortage crisis, the talukas of Ponda and Tiswadi have been facing a new water-related problem.
The taps in the areas are pouring out turbid water.
Following restart of the monsoon in the Ghat area, the Opa plant received highly turbid water. The turbidity was 182 Nephelometric Turbidity Unit (NTU) on Wednesday morning as against 45 NTU on Tuesday.
Such high levels of turbidity in the Opa river were seen only during the days when mining operations were on in the upstream region of the Khandepar river.
In March 2018, mining operations in the state came to a halt and the problem subsided. It, however, surfaced on July 6, 2018, and August 17, 2018, when turbidity touched 358 NTU. Thereafter, turbidity was recorded only on August 8.
Explaining the reason behind the turbidity seen on Wednesday, an official of the water resources division has claimed that the pits inside mines fill with water during the monsoon which leads to silt washing off from the area and into the river water.
High turbidity levels cost the state exchequer dearly, as several million litres of water are needed to clean the clogged filters every year as the filters quickly become non-functional due to the density of mining sediment. On an average, about three million MLD water is used to backwash the filters. The Opa water treatment plant has 21 filters of various sizes.
With the turbidity shooting to 182 NTU, the filters were heavily clogged and necessitated a time-consuming clean-up to ensure safe drinking water for consumers, he said.
After raw water is drawn into a receiving chamber from the river, it flows into sedimentation tanks to allow settling of silt. Next, the water passes through three stages. It is passed through sand filter beds to the chlorination plant before going into the main balancing reservoir for storage and supply.
Sometimes consumers receive turbid water if there is power shutdown at the plant, resulting in sedimentation of fine silica in the water reservoirs, corrosion of domestic connection lines, besides various health hazards.