Not Just a Weed: Water Hyacinth in Pluit Reservoir Can Disrupt Pumps and Increase Flood Risk

JAKARTA – The emergence of water hyacinth that previously covered the surface of Pluit Reservoir in Penjaringan, North Jakarta, is considered to potentially disrupt the performance of flood control infrastructure.

Lecturer at the School of Environmental Science, University of Indonesia, Mahawan Karuniasa, stated that the presence of large quantities of water hyacinth not only affects the reservoir’s appearance but can also hinder the hydraulic system.

“If water hyacinth covers the surface and clogs operational areas, the risks are not just aesthetic and odour-related, but also hydraulic disruptions, reduced pump efficiency, declining water quality, and accelerated organic sedimentation,” he said when contacted by Kompas.com on Thursday (2/4/2026).

According to him, the presence of water hyacinth can disrupt water flow and reduce the effective storage capacity of the reservoir.

“In extreme rainfall scenarios, such obstructions can increase the risk of flooding,” he added.

Furthermore, Mahawan assessed that the massive growth of water hyacinth also indicates pollution pressure in the reservoir’s waters, generally related to high levels of nutrients such as nitrogen and phosphorus.

“Water hyacinth blooms are almost always an alarm for eutrophication: water is too rich in nutrients,” he said.

“So this issue must be read as a risk to urban infrastructure, not just a wild weed,” he emphasised.

He stressed that handling water hyacinth is not sufficient with just transportation, but also requires controlling pollution sources and coordination of management from all related parties.

“If the pollution load comes from a river system crossing multiple areas, then this is a layered responsibility: DKI at the downstream, provinces/regencies in the transit areas, and the Central Government as the manager of inter-provincial river areas,” he added.

Previously reported, the emergence of water hyacinth plants covering part of the surface of Pluit Reservoir in Penjaringan went viral on social media.

A video uploaded by the account @ilhamapriyanto showed the increasingly widespread distribution of water hyacinth in Pluit Reservoir on Tuesday (31/3/2026). The aquatic plant appeared to cover part of the water body, disrupting the reservoir’s appearance.