Which water system uses a reservoir or river as a water source and has automatic pressure controls to maintain a constant pressure?

The direct pumping system is characterized by its use of mechanical pumps to draw water from a reservoir or river and deliver it to users while maintaining consistent water pressure. This system incorporates automatic pressure controls, ensuring that the water pressure remains stable and within the required parameters for effective distribution.

In this scenario, when water is needed, pumps activate to transport the water, making it highly responsive to demand fluctuations. This capability is essential when immediate adjustments in pressure are required, such as during peak usage times or in emergency situations.

Other types of systems serve different functions. A gravity-fed system relies on the natural force of gravity to move water from a higher elevation to a lower elevation, rather than using pumps, which limits its control over pressure. A pressurized system exists primarily through generated pressure but does not necessarily involve water sources like reservoirs or rivers, focusing instead on maintaining pressure without the aid of pumps for sourcing. Finally, a combined system involves elements of both gravity and pumps, yet it doesn't specifically highlight the automatic pressure control feature in the same manner as the direct pumping system.