Q1: For trunk sewers more than 1.25 m in diameter, the ratio of the maximum daily sewage flow to the average daily sewage flow is assumed

ANS:A - 1.5

The value of 1.5, as mentioned in the context of the ratio of maximum daily sewage flow to average daily sewage flow for trunk sewers more than 1.25 m in diameter, would imply a more conservative design assumption. If the ratio were assumed to be 1.5, it suggests that the maximum daily sewage flow is only 1.5 times higher than the average daily sewage flow. In practical terms, this indicates that the sewer system is designed with less capacity to handle peak flow rates compared to other design ratios. Designing with a ratio of 1.5 may be appropriate for certain scenarios where there are limitations on available resources or where the variability in sewage flow is relatively low. However, in many cases, a higher ratio, such as 2.0 or greater, is commonly used to ensure adequate capacity and resilience in the sewer system to handle peak flow conditions effectively. While a ratio of 1.5 may be feasible for smaller sewer systems or in situations where peak flows are well understood and predictable, it may not provide sufficient capacity to handle unexpected surges in sewage flow or accommodate future population growth and urban development effectively. Therefore, design engineers often consider various factors and standards when determining the appropriate ratio for sewer system design.