Wallingford's procedure for runoff estimation is a well-known methodology, especially in the UK. It's used for estimating urban stormwater runoff in drainage design. Here's a detailed table about the Wallingford procedure:
| Aspect | Details with Emojis |
|---|---|
| Origin 🌍 | Developed by the HR Wallingford group in the UK. |
| Primary Use 🛠️ | Urban stormwater runoff estimation for drainage and sewerage system design. |
| Core Principle 🧠 | Uses a unit hydrograph and rainfall depth to predict runoff hydrographs for a given rainfall event. |
| Components 📊 | - Rainfall Profile: Defined using the time of concentration and a design storm profile. 🌧️\ |
- Unit Hydrograph: Represents runoff response to a unit of rainfall. 💧\
- Runoff Volume: Determined using impermeable area and rainfall depth. 🌊 | | Variables 🔢 | - Time of Concentration (Tc): Time taken for water to travel from the most distant point in the catchment to the outlet. ⏱️\
- Rainfall Intensity: Typically derived from Intensity-Duration-Frequency (IDF) curves. 📈\
- Impermeable Area: Surface areas that don't allow water infiltration, such as roads or buildings. 🏢🛣️ | | Applications 🏙️ | Commonly used in the design of urban drainage systems, including:\
- Stormwater drainage networks\
- Sewer systems\
- Flood risk assessments | | Advantages ✅ | - Relatively simple and requires fewer parameters than some other methods.\
- Widely accepted and used, especially in the UK.\
- Suitable for small to medium-sized urban catchments. | | Limitations ❌ | - May not be as accurate for larger or complex catchments.\
- Assumes a fixed proportion of rainfall becomes runoff, which might not be accurate for all scenarios.\
- Might not account for all complexities in real-world scenarios. |
This table provides a comprehensive overview of the Wallingford procedure for runoff estimation. It's worth noting that while the Wallingford method is valuable, it's essential to consider the specific requirements and conditions of a project when choosing a runoff estimation method.
