Suitability of village pond waters for irrigation-a case study from district Ludhiana, India.

The village ponds were used for storing rainwater for animals and recharging of underground water. Recent developments like public water supply for household purpose, provision of household wastewater concrete channels, and toilet septic tanks have polluted the village ponds. The infiltration of water has decreased due to non-cleaning of silt from the pond beds. Increased discharge of wastewater from households, coupled with a low infiltration rate, has inundated these ponds. People have abandoned the use of this water for animals. An effort has been made to assess the suitability of this water for irrigation in the vicinity so as to clean these ponds. Seventy-eight water samples were collected from the village ponds in the Ludhiana district of Punjab. The samples were analyzed for total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD), electrical conductivity (EC), residual sodium carbonate (RSC), nitrogen, water soluble P and K, as well as micronutrients and pollutant elements. The total solids content of these waters were on the higher side. Considering TSS, BOD, and COD, some of these waters are unsafe for their disposal in river or water bodies. Electrical conductivity ranged from 693 to 5050 μmhos/cm, and RSC varied between -1.9 and 22.8 meq/l. The inorganic N (NH+₄+ NO-₃-N) and total Kjeldahl N ranged from 3 to 30 and 8 to 41 mg/l, respectively. The amount of micronutrients (Zn, Cu, Fe, and Mn) present in pond water indicated its high nutrient value. The content of the pollutant elements such as nickel, cadmium, and lead was below the maximum permissible limits, thereby indicating its suitability for irrigation. According to the EC and RSC criteria, 18% of the samples were fit, 31% were marginal, and 51% were unfit for irrigation. The data indicate that these waters are a good source of nutrients for agriculture.