Catchment Hydrology Introduction

A fully developed catchment refers to the design of a drainage system that caters for flows discharged from a fully developed area.

False (B)

The longevity (sustainability) of these surface storages must be ensured through appropriate measures like containment within easements or reserves to prevent potential issues like flood storage system failures.

<p>The chosen method should be suitable for the catchment conditions, meet the required accuracy level, and be capable of assessing critical changes in the specific condition being evaluated.</p> Signup and view all the answers

<p>The Rational Method may not be appropriate when dealing with areas of significant urban development. (A), The Rational Method may not be suitable for catchments with significant surface water storage systems. (B), Complex catchments can have various unique conditions, such as low gradient land with oval or park areas that require a more sophisticated approach to accurately assess and predict flow behavior. (C), The Rational Method is not always suitable for irregular or oddly shaped catchments. (D), The method should be handled with care in catchments where travel times for drainage systems vary significantly. (E), Large catchments often have land with diverse runoff characteristics that need specialized treatment. (F), The Rational Method should be used with cautious consideration for catchments with drastic changes in slope. (G), Urban catchments with areas exceeding 500 ha pose challenges for the application of the Rational Method. (H), The Rational Method is a simple method with limitations. It is often used to check (not calibrate) numerical models which can help to avoid gross errors. (I)</p> Signup and view all the answers

<p>Runoff-routing models are essential tools for analyzing and designing urban drainage systems, particularly in complex situations.</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Assessing potential future conditions can be difficult especially when such conditions may be outside of the designer's direct control and knowledge. (A), The presence of flow attenuation mechanisms can significantly influence future conditions requiring careful consideration. (B), Changes in upstream catchments can impact downstream drainage, creating uncertainties about future conditions. (C), The design drainage has to account for a wide range of potential future conditions, including land use changes and stormwater mitigation. (D), The drainage designer may not have access to reliable information regarding future conditions, making accurate predictions challenging. (E)</p> Signup and view all the answers

<p>The intent is to select a method that is appropriate for the catchment conditions and provides the desired level of accuracy for the intended purpose of the project.</p> Signup and view all the answers

<p>All of the above. (D)</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

<p>Urban catchments with an area greater than 500 hectares. (C)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>All of the above (D)</p> Signup and view all the answers

<p>5 minutes (B)</p> Signup and view all the answers

<p>Standard inlet time (A), Creek flow travel time (B), Concentrated overland flow (C), Overland sheet flow (F), Channel flow time (G), Kerb flow time (H)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>To represent the travel time from the top of the catchment to a location where the first gully or field inlet would normally be expected to exist.</p> Signup and view all the answers

<p>8 minutes (D)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>The catchment is predominantly piped or channelized. (C)</p> Signup and view all the answers

<p>Horton's surface roughness factor.</p> Signup and view all the answers

<p>t = 0.025 * L/S^.5 (minutes)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

<p>An elongated pipe system extending further upstream. (C)</p> Signup and view all the answers

<p>Intensity-frequency-duration (IFD) data</p> Signup and view all the answers

<p>Determining the optimal type and size of pipes for a drainage channel. (C)</p> Signup and view all the answers

<p>Both A and B (B)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

<p>Both A and B (B)</p> Signup and view all the answers

<p>Cv (composite) = Cv (pervious) * (A - A(imp.)) + A(imp.)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>1.0</p> Signup and view all the answers

<p>To compensate for flow attenuation effects caused by floodplain storage when using the Rational Method (C)</p> Signup and view all the answers

The study of water flow within a drainage area for designing drainage systems.

To select appropriate methods, understand their application, apply them correctly to determine design discharges, and create a drainage system that protects assets for its whole lifetime.

Methods that are suitable for the specific properties of the drainage catchment.

The estimated flow rate used to design a drainage system.

The characteristics of land use and flow mitigation systems in the drainage area above the design location.

A local document outlining land use plans and regulations.

A plan that outlines the local government's planned infrastructure, including drainage systems.

Local rules and regulations for development applications relating to water management.

The most extreme condition a drainage system is expected to handle during its lifespan.

A catchment with maximum land use, taking into consideration all possible flow mitigation measures.

Methods to reduce the peak flows from a catchment.

A system to store water temporarily to reduce peak flows.

Principles for designing urban areas to manage water sustainably.

Structures that temporarily store water.

Designated areas for drainage-related infrastructure.

A situation where an undersized drainage system impedes water flow, leading to surface water pooling.

The maximum anticipated land use and development in a catchment.

To analyze water flow in a drainage area to design a system that protects assets and meets local regulations.

Choosing methods appropriate for the specific properties of the drainage area.

Knowing how to apply the chosen methods correctly based on the specific catchment's conditions.

Calculating the maximum expected flow rate for the drainage system's design.

To protect public and private assets from flooding throughout the drainage system's lifespan.

Predicting the characteristics of land use and flow mitigation in the future.

Local governments provide information on future land use and regulations.

Provides information on anticipated land use and development in the area.

Outlines local government's planned infrastructure, including drainage systems.

To guide development applications related to water management.

The most extreme condition the drainage system is designed to handle.

Assuming that future conditions include maximum land use and development.

Current discharges may exceed future conditions due to existing mitigation systems or planned changes.

Large-scale systems designed to store and manage stormwater runoff.

Designing for flows from a fully developed catchment to ensure a long-lasting system.

Design assumptions should align with approved planning schemes and codes.

Assuming the maximum anticipated land use as outlined in the planning scheme.

Including flow attenuation systems if they are mandatory in the planning scheme.

Examples include detention ponds and WSUD principles for managing stormwater.

Including existing surface storages in the design if they are protected.

Ensuring that surface storage areas are protected from encroachment.

Ignoring surface storages that are not protected or are temporary.

Storage created by an undersized drainage system that will likely be removed during upgrades.

Flooded urban areas may need to be considered in the design.

Evaluating the types of risks associated with the drainage design, considering potential consequences.

Analyzing the flow of water through the catchment, including land use impacts and mitigation strategies.

Providing clear reasons for the design assumptions used in the project.