RIVER CHANNEL CALCULATIONS

Slides:

Advertisements

Similar presentations

River study. Introduction Rivers usually follow three stages: the upper, middle and lower courses. Each stage has its typical features. The upper course.

Advertisements

Characteristics of High Gradient Streams

Introduction and theory

GCSE Geography Enquiry

Higher Hydrosphere The Upper Course Areas with steep gradients will have an increased velocity and so the potential for erosion is higher, especially vertical.

L.O: Investigate river variables that change from source to mouth. All MUST identify which variables increase and decrease (D). Most SHOULD explain the.

Part 2 Quit Landforms and exogenetic processes 2.2 How can a river change the land?

River Studies. Outline of Events During your river field work you will be visiting two different sites in the lower course of the river. At each site.

End of Chapter 4 Movement of a Flood Wave and begin Chapter 7 Open Channel Flow, Manning’s Eqn. Overland Flow.

River Systems - Runoff.

A rivers long profile looks something like this:

Hydraulics Engineering

Hydrologic cycle` I. Hydrologic Cycle: the movement of water through and over the Earth Water continuously traveling between oceans, atmosphere, continents,

Pertemuan Open Channel 1. Bina Nusantara.

G.C.S.E Controlled Assessment An investigation of river erosion along a chosen stretch of river.

Part 2 Some Basic Aspects of CHANNEL HYDRAULICS. The volume of water that passes by any given point along a watercourse is called “Q”, for quantity of.

FIELD METHODS IN ENVIRONMENTAL GEOLOGY GEOS 3110.

Hydrology and Water Resources RG744 Institute of Space Technology December 11, 2013.

Freshwater – IB Geography

Water Cycle - Running Water

Running Water & Groundwater

Whiteboard Warmup: AP FRQ from 2005

Hydraulic Engineering

© Oxford University Press 2009 Managing river and coastal environments: A continuing challenge 2.2What are the major fluvial processes? Part A.

Streams and Drainage Systems The most important source of moving water.

September 2014 Lesson on: River Environments Keyword 1.River Key question 1.What are the key features of a river? Dwight Sutherland 2014.

CHANNEL EFFICIENCY Channel Roughness. It is often thought that the velocity of a river is greatest near its start. This is not the case, as large angular.

Lesson 9 Channel characteristics

RIVERS AN INTRODUCTION.

Streams Nancy A. Van Wagoner Acadia University Distribution of Earth's water n What are the percentages? -Oceans - Glaciers - Groundwater - Lakes and.

STORMWATER MANAGEMENT Manning’s Equation for gravity flow in pipes & open channels.

Stream Erosion and Transport

River Channel Tutorial Start By using the distance and depth data of a river channel, the cross-section can be drawn. End.

What is the long river profile? The gradient is less steep than in the upper course. The valley gets wider and flatter. Erosion is more lateral (or.

How to Calculate Area, Perimeter, and Volume By Trayvona Ford

Lecture 13 Design of erodible and non-erodible, alluvial channels- Kennedy’s and Lacey’s theories.

Water Quality and Water Testing. Studies of streams may involve the following measurements and analysis 1.Physical Parameters of the Stream 2.Biological.

EROSION- The transport of weathered materials…. Major Erosive Agents: Running Water GLACIERS WIND OCEAN CURRENTS AND WAVES MASS WASTING (GRAVITY!)

Bradshaw Model. Upstream Downstream Discharge Occupied channel width Channel depth Average velocity Load quantity Load particle size Channel bed roughness.

13.1 Streams and Rivers Key Idea:

We have been looking at how the valley changes downstream.

Data Presentation. What the mark scheme says: Section A - Channel Shape.

RIVERS THE MIDDLE COURSE.

R IVERS Research Review. F ACTORS THAT A FFECT R IVER V OLUME Size of Drainage Basin large drainage basin= several tributaries= more volume Vegetation.

Aims today: To learn about: Channel Efficiency The Hydraulic Radius

River characteristics. What happens to a river as it goes from source to mouth? It gets Wider Deeper Faster Stones gets smaller and rounder.

1 Unit 2 River processes produce distinctive landforms in their valley.

Hydrology and Water Resources RG744 Institute of Space Technology November 13, 2015.

Channel Processes and Hjulstrom’s Curve

LO – To understand the changes in river process with distance from source - To understand Long and Cross Profiles of a river.

What is the Bradshaw model?

Open Channel Hydraulic

Outside! The map below shows a meandering river. Points

You have 1 minute to identify and write down as many key terms as possible for each of the following photos...

Expression Session Summarise “stream discharge” and “river load” using diagrams to assist your answer.

DO NOW Pick up notes and Review #30. Have your turned your lab in?

Chapter 6.1 Running Water.

Discharge, stream flow & channel shape

Hydrological Research fieldtrip

Stream Erosion.

Rivers and Streams.

PAPER 3: Geographical Applications

Weekly lesson objectives

Streams and Drainage Systems

Wind Erosion Sandblasting (abrasion) – occurs when winds blow sand or silt grains against rocks and other objects Lower portions of rocks become more eroded.

Changes in a river from source to mouth

Factors that Affect River Flow

Rivers and Streams.

Scour Analysis on the west fork of the Duchesne River

Presentation transcript:

RIVER CHANNEL CALCULATIONS Use this info to complete page 5 and 6 of the latest notes packet you have been given Answer all the questions using the info in this PowerPoint

What is the Wetted Perimeter? The yellow line shows the wetted perimeter Wetted perimeter: the part of the bed and banks which is in contact with the water in the channel – how do you think hydrologists measure this?

This river has a higher wetted perimeter in comparison to its volume, The difference in the wetted perimeter of a river between the upper and Lower course of a river 5 meters This river has a higher wetted perimeter in comparison to its volume, which increases friction and reduces Velocity (upper course) Rocks and boulders 50 meters This river has a smaller wetted perimeter in comparison with its volume, because it has smooth banks, friction is reduced and this allows velocity to increase (middle/lower course) http://www.youtube.com/watch?v=mgBqfcMK4jI

Calculating the wetted perimeter Wetted perimeter: the part of the bed and banks which is in contact with the water in the channel – how do you think hydrologists measure this? Calculating the wetted perimeter This can be done using a weighted tape measure If the stream has a rectangular shape, with no rocks and boulders in the channel like the one below The wetted perimeter can be calculated by multiplying the depth by 2, and adding the width Wetted perimeter= 10 x 2 = 20 20 + 20 = 40 meters Av. Depth 10 meters Width 20 meters

Hydraulic radius (Rh): the ratio between the area of the cross-section of a stream and the length of its wetted perimeter – it measures channel efficiency A square-shaped stream cross-section has a larger hydraulic radius than a shallow, rectangular-shaped stream cross section The higher the hydraulic radius, the faster the river flow (Velocity) and the more efficient the river is, because there is less contact between the water in the channel and the bed and banks, so lower friction. (cross sectional)

Velocity & Discharge Discharge is the amount of water that passes a given point on the stream every second- measured in cubic meters a second (cumecs) Velocity is the speed of the water moving, measured as the distance traveled every second. Speed = Distance\Time Time how long it takes for a cork to travel 50cm (using the meter stick/ tape measure)

Measuring discharge in Cumecs (m³/s ) In order to calculate the discharge of a river in cumecs (cubic meters per second), you need to calculate the cross sectional area (m) (width x depth) and times this by the velocity (speed in meters a second) Width = 10 meters Speed of flow (velocity) = 10 meters a second Discharge in cumecs= 15 x 10 = 150 cumecs Depth = 1.5 meters 10 x 1.5 = 15 (cross sectional area)

3) The wetted perimeter (rectangular hypothetical streams) Width = 12 meters Speed of flow (velocity) = 11.3 meters a second 1) Av.Depth = 3 meters Width = 32 meters Speed of flow (velocity) = 15.6 meters a second 2) Av.Depth = 4.3 meters Calculate the: 1) Cross sectional Area 2) Discharge in cumecs 3) The wetted perimeter (rectangular hypothetical streams) 4) Hydraulic radius of these hypothetical rivers (show your working out) Width = 56 meters Speed of flow (velocity) = 34 meters a second 3) Av.Depth = 9.6 meters Width = 2 meters Speed of flow (velocity) = 8 meters a second 4) Av.Depth = 0.8 meters Speed of flow (velocity) = 16 meters a second Width = 23 meters 5) Av.Depth = 1.7 meters

3) The wetted perimeter (rectangular hypothetical streams) Width = 43.7 meters Speed of flow (velocity) = 2 meters a second 6) Av.Depth = 7 meters Width = 32.1 meters Speed of flow (velocity) = 0.2 meters a second 7) Av.Depth = 5.8 meters Calculate the: 1) Cross sectional Area 2) Discharge in cumecs 3) The wetted perimeter (rectangular hypothetical streams) 4) Hydraulic radius of these hypothetical rivers (show your working out) Width = 68 meters Speed of flow (velocity) = 2 meters a second 8) Av.Depth = 11.3 meters Width = 2.8 meters Speed of flow (velocity) = 3.0 meters a second 9) Av.Depth = 15.9 meters Speed of flow (velocity) = 2.8 meters a second Width = 23.7 meters 10) Av.Depth = 2.7 meters

Data Analysis Which is the most efficient stream? Which stream has the narrowest channel? Which stream has the largest wetted perimeter? Which stream has the highest discharge in cumecs? Which stream has the lowest discharge in cumecs? Which stream has the deepest channel? Which stream has the widest channel? Which stream has the fastest velocity? Bonus: Which stream would be causing the most erosion and transporting the most load? Why?