Ludhiana, August 30
Soil chemists from Punjab Agricultural University (PAU) have more bad news. Only a while ago they had shown that the concentration of heavy metals like lead, chromium, cadmium and nickel in the groundwater around Budda Nullah was 21, 133, 280 and 300 times higher, respectively, than the permissible limits.

The latest, yet unpublished study of the Department of Soils, adds more fright to the situation. Guided by senior soil chemist M.S. Brar, the study trails the path of heavy metals into soil, underground water and finally vegetable crops.

Comparing sewage water from Budda Nullah with tubewell water, the investigators have found the concentration of nickel to be 2200 times higher in the nullah water as compared to the latter. Cadmium in sewage water is 700 times higher than in tubewell water. Corresponding figures for nickel and cadmium, until the last study, were 300 and 280, respectively.

“The increase is indicative of the rate at which nickel and cadmium are affecting water and soil,” Dr Brar told The Tribune. He added that the concentration of chromium and nickel in nullah water was much above the permissible limits for their disposal on farmlands. The new study also shows that heavy metal pollution has severely contaminated shallow water sampled from hand pumps close to Budda Nullah, besides impairing the soil irrigated by nullah water.

The level of chromium, nickel, cadmium and lead in the soil irrigated by sewage water is 35.5, 14.3, 3.6 and 1.8 times higher than in tubewell water irrigated soil, respectively. And that’s not all. These metals are getting absorbed into crops and are settling down in the edible portions in larger quantities than in leaves. No wonder some farmers along the banks of Budda Nullah have stopped using sewage water for irrigation.

Mewa Singh and Dalbir Singh from Dhanasu village are among them. Alarmed by PAU findings, they have stopped releasing drain water on farmlands. But not all farmers are ready to forego the convenience of pumping water from a drain that flows in their backyard. But they better be, unless Budda Nullah is put back on the path of recovery.

Right now the nullah has no dissolved oxygen and it does not recover through self-purification mechanism. The BOD (Biological Oxygen Demand) level is also very high — 250 mg per litre caused by discharge of organic waste. Explains Dr G.S. Dhillon, a water resources development expert, “In the absence of dissolved oxygen, anaerobic bacteria work on the organic pollution load and produce hydrogen sulphite which causes stench and blackness of water. In such water aquatic life cannot exist.”

Time was when Budda Nullah had 56 species of fish. The numbers fell to 18 in 1970s, courtesy Municipal Corporation, which had begun dumping domestic waste into the Nullah. “By 1984 only four fish had survived – all air breathing,” says Dr H.S. Sehgal, Head, Zoology Department, PAU, adding: “Now Budda Nullah neither has fish nor plankton, which is an indicator of biodiversity.”

Experts still feel the stream can recover if there is enough political will to aid the process. The immediate solution lies in treatment of domestic and industrial waste. Punjab Water Supplies and Sewerage Board is constructing three domestic Sewage Treatment Plants (STPs) at Bhatian, Jamalpur and Balloke in Ludhiana. The combined capacity of these STPs proposed under the Sutlej Action Plan is 300 million litres a day.

Mr Pradeep Choudhary, the Board Chief Engineer, says: “We want to bring the Nullah’s BOD level down to 30 mg a litre. Bhatian plant will be commissioned by October. The rest will be completed next year.” Incidentally, the 230 crore plan was approved by the Government of India in 1995, but progress has been lax. Even when these plants become operational, they will be no good unless industrial effluents are treated in effluent treatment plants.

Representatives of industry, especially Tajpur Dyeing Association, have been operating their ETPs for long. But they prefer a Common Effluent Treatment Plant (CETP) to cut costs. Association President Ashok Makkar says: “We are ready to install a CETP for 50 dyeing units located on Budda Nullah banks. Let state government give us land.” Till then, the MC can start de-silting the Nullah to prevent sewage solids from settling down and decomposing.