Ocean Disposal of Wastewater

The following sections are included:

• Preface

• Acknowledgements

• Table of Contents

• List of Figures

The ocean has for all time been the ultimate sink for water-borne waste products coming from the land. Rivers and small creeks have always carried silt into the ocean and since the development of agriculture the products of the runoff from cultivated and pastoral land have gone via the rivers into the ocean. More recently the waste from urban and industrial communities has been disposed of in the ocean. This effluent, which is a very dilute mixture of human and other waste, is normally collected in a pipe system which carries it to a central location. After treatment, the effluent is discharged into the ocean. The disposal is carried out by constructing a pipeline on the bed of the ocean with a diffuser (Figure 1.1) or with a tunnel, risers and appropriate diffusers (Figure 1.2). The effluent, which has a density close to that of fresh water, rises to the surface and in doing so entrains the surrounding salt water and becomes very dilute …

The following sections are included:

• Introduction

• Bacterial Standards For Water in Regions Where Shellfish Are Collected

• The Bacterial Standards For Bathing And Water Contact Sports

• The Protection Of Marine Life And Aesthetic Standards

• The Means Of Achieving These Standards

The following sections are included:

• Introduction

• The Untreated Effluent

The following sections are included:

• Introduction

• The Pure Axisymmetric Jet

• The Axisymmetric Vertical Plume

• The Buoyant Plume Ejected at an Angle to the Vertical

• The Implications of the Spread Assumption

The following sections are included:

• Introduction

• The Velocity Buoyancy Distributions

• The Spread Equation

• The Equations for a Single Jet Within the Plane of Symmetry

• The Zone of Flow Establishment (The Initial Zone)

• A Comparison of the Theory and Experiments

The following sections are included:

• Introduction

• The Calculations in the Region Below the Point at Which the Two Two-dimensional Buoyant Jets Merge

• The Calculations for the Region Above the Point at Which the Two Two-dimensional Buoyant Jets Merge

• The Numerical Procedure

• The Results of Dilution Calculations

The following sections are included:

• Introduction

• The Two-dimensional Surface Plume

• The Axisymmetric Surface Plume

• The Finite Length Diffuser

The following sections are included:

• Introduction

• The Horizontally Spreading Region

• The Flow Below the Equilibrium Region

• The Flow Above the Equilibrium Region

• The Computed Results

The following sections are included:

• The Pipe Diameter

• The Port Diameters

• The Effluent Dilution

• Summary

The following sections are included:

• Introduction

• Computer Solution

• Manual Solution

The following sections are included:

• Introduction

• The General Equations For a Flow With Gaussian

• Distributions of Velocity and Buoyancy

• The General Equations For the Flow With Vortex Like Distributions

• Discussion of the Limiting Cases

• The Condition For the Transition Between the Gaussian and Vortex Like Flows

• The Matching of the Flows at the Transition Section

• The Conditions at the End of the Zone of Flow Establishment

• Conclusion

The following sections are included:

• Introduction

• The Numerical Model Equation

The following sections are included:

• Introduction

• The Flow Regime Classification

The following sections are included:

• Introduction

• Deep Diffuser in Which Jets are Merged for a Large Part of Their Depth and the Rising Effluent Behaves as a Two-dimensional Plume (Brooks 1979)

• The Dimensional Analysis Approach for a Deep Diffuser

• The Experiments With Merging Plumes

• Experiment With Merging Plume in a Stratified Environment

The following sections are included:

• Introduction

• Setting up an Oceanographic Study

• Eulerian Current Measurements

• Lagrangian Current Measurements

• Effluent Field Diffusion Measurements

The following sections are included:

• Introduction

• Pathogens and Indicator Concepts

• Faecal Indicator Bacteria

• Inactivation of Indicator Bacteria

The following sections are included:

• Introduction

• Oceanographic Data Requirements

• Approaches to Advection-Diffusion Modelling

• A Current Field Which Does Not Vary With Position or Time

• A Current Field Which is Spatially Constant but Varies with Time According to a Current Meter Record

• A Current Field Which Varies Temporally and Spatially According to a Computations Model

The following sections are included:

• Introduction

• Physics of Outfall Purging

• Development of a Purging Criterion

• Effluent Flow in Outfall Tunnel

• Seawater Intrusion

• Hydraulic Modelling of the Tunnel Riser Combination

• Modelling for Plume Dilution

• Recommendations for Design

The following sections are included:

• Introduction

• The Hastings Outfall Monitoring Programme

• The Sydney Outfalls Monitoring Programme

• Conclusion

• The Hydraulic Performance of the Outfall Diffuser

The following sections are included:

• Introduction

• The Outfall Pipe Foundations

• The Forces on the Outfall Pipe and its Foundations

• Outfall Pipe Material and the Methods of Construction

The following sections are included:

• Appendices

• References

• Index