**Methods of Estimating High Flood Discharges**

When it comes to estimating high flood discharges, engineers and hydrologists have developed several methods to determine the magnitude of potential flood events. These methods take into account various factors such as historical data, statistical analysis, and regional characteristics. However, there are certain methods that are commonly used, while others are not suitable for estimating high flood discharges. In this response, we will discuss the methods that are used in estimating high flood discharges and identify the one that is not suitable for this purpose.

**1. Percent Flood Risk Method**
- This method involves determining the acceptable level of flood risk for a specific project and estimating the corresponding flood discharge. It takes into account factors such as the consequences of flooding, the economic impact, and the level of protection required.
- However, this method is not suitable for estimating high flood discharges as it is focused on determining the acceptable level of risk rather than accurately quantifying the magnitude of potential flood events.

**2. Stochastic Methods**
- Stochastic methods involve the use of probability and statistical analysis to estimate high flood discharges. These methods consider the random nature of flood events and use historical data to determine the probability of different flood magnitudes occurring.
- Stochastic methods are commonly used in flood hydrology and are particularly useful for estimating extreme flood events. They provide a probabilistic estimate of flood discharges based on historical data and statistical analysis.

**3. Flood Frequency Studies**
- Flood frequency studies involve analyzing historical flood data to establish a relationship between flood magnitude and frequency. By examining the frequency of different flood magnitudes, engineers can estimate the magnitude of potential high flood discharges.
- This method is widely used in hydrology and provides a systematic approach to estimating flood discharges based on historical records. It considers the frequency of different flood events and can provide valuable insights into the potential magnitude of future floods.

**4. Empirical Formula Developed for the Region**
- Empirical formulas are developed based on historical flood data and regional characteristics. These formulas establish a relationship between certain parameters such as watershed area, rainfall intensity, and flood discharge.
- By applying these empirical formulas, engineers can estimate high flood discharges for a specific region. These formulas take into account regional characteristics and can provide a reasonable estimate of flood magnitudes.
- However, it is important to note that empirical formulas should be used with caution as they are based on assumptions and may not accurately represent the unique characteristics of every flood event.

**Conclusion**
- In conclusion, the method of estimating high flood discharges that is not suitable for this purpose is the percent flood risk method. This method focuses on determining the acceptable level of flood risk rather than accurately quantifying the magnitude of potential flood events. In contrast, stochastic methods, flood frequency studies, and empirical formulas developed for the region are commonly used to estimate high flood discharges. These methods consider historical data, statistical analysis, and regional characteristics to provide a more accurate estimation of flood magnitudes.