Why did the port of Surat declined at the end of 18th century?

A network of a variety of Indian merchants and bankers were involved in the export trade, financing production, carrying goods and supplying exporters. Supply merchants linked the port towns to the inland regions. They gave advances to weavers, procured the woven cloth from weaving villages, and carried the supply to the ports. At the port, the big shippers and export merchants had brokers who negotiated the price and bought goods from the supply merchants operating inland. By the 1750s this network, controlled by Indian merchants, was breaking down. The European companies gradually gained power – first securing a variety of concessions from local courts, then the monopoly rights to trade. This resulted in a decline of the old ports of Surat. The same happened with Hooghly.