When dealing with a low water pressure area, inserting a second engine into the relay can significantly enhance the overall pressure and flow of water being delivered. This approach allows for additional pumping capacity to compensate for the inadequacies of pressure in the existing setup. By adding another pump, the system can achieve greater pressure, effectively overcoming the challenges posed by low water pressure zones, and ensuring that the needed water flow reaches the required destination, whether it's for firefighting or other emergency operations.
Using larger diameter hoses might seem beneficial as it can reduce friction loss, but it may not directly address the underlying issue of low pressure. Increasing pump speed could lead to cavitation or other mechanical issues if not managed properly, especially in a system already facing inadequate pressure. Reducing water flow would only exacerbate the problem of low pressure, making it counterproductive. Therefore, the most effective way to adapt operations in a low water pressure area is by adding another engine to the relay, which provides a more robust solution to ensure effective water delivery.