Floating aquatic plants- A challenge for operation of irrigation canals in Punjab Pakistan and way forward

The problem of entry of unwanted floating matter (aquatic plants) has been persisting for many years and is increasing gradually in Indus River Basin Irrigation System (IBIS). It is causing hindrance in smooth flow of water in irrigation network starting from the barrages to the main canal, branch canals, distributaries, minor canals, and water courses. Under this study Pakpattan Canal has been selected for detailed survey and sampling of floating material. Results of the study have diagnosed that aquatic plants as the “water hyacinth”. Survey of Sulemanki Headworks and Pakpattan Canal indicated that aquatic plants grow in abundance at upstream of Sulemanki Headworks in the form of contiguous colonies. The plants are also growing in different patches along the berm of Pakpattan Canal. These aquatic plants appear to have some entry from Ravi River through Balloki Sulemanki Link Canal as these also exist in the form of scattered colonies along the sides of Ravi River upstream Balloki Headworks. Keeping in view the ecosystem for controlling the water hyacinth, chemical control method is least recommended as it may deteriorate the water quality. Mechanical methods may be used as a short-term strategy but it may be costly. The runoff control method is a good tool for its minimal proliferation. Biological control may produce classical results with the least adverse effects. Chinese Grass Carp fish may be used in off-season (stagnant waters) where water hyacinths (aquatic plants) are in a huge quantity forming colonies. Overall, an integrated management strategy may be adopted to mitigate the problem of un-wanted floating plants to ensure smooth flow in water channels.