Sump surface intake is a surface water method where water from a stream or lake/reservoir is led through a pipe to a well or sump in river bank, where suspended matter can settle before extraction. Intake is equipped with screen or gabion to avoid debris in pump. Intake might be downstream from dam to allow for a sufficiently high water level.
River flow decisive for supply volume and expenses of intake. Costs depend on specific design. In most simple form only pipe and sump have significant costs, other methods include expenses for dam construction and river bank stabilization.
Can be implemented at local level, possibly even by users. Bigger intakes for large user groups can be implemented by a water company or another local authority. Management is likely to be combined with the managing of water treatment.
Not suitable for very shallow rivers. Locating downstream from agricultural activities and settlements increases risk of contamination. Over-abstraction affects sustainable use and ecosystem. Risk of clogging by silt or debris. Hence, the positioning of intake is very critical. Bank erosion can be damaging to inlet and pipe system.
Low water table may prompt dam construction. Daily operation includes inspecting inlet and adjusting valve or sluice. Infrequent cleaning of inlet, screen reparation and erosion damage control is necessary. O&M can be done by caretaker with only basic skills.
Water quality is of concern necessitating awareness-raising campaign on contamination hazards. In the wet season high turbidity is likely and might cause problems. Extracting large water volumes might lead to social friction with users downstream.
No relevant remarks for Sump surface intake.