dr. martin t. auer mtu department of civil & environmental engineering surface water quality

Post on 20-Jan-2016

215 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

TRANSCRIPT

Dr. Martin T. AuerMTU Department of Civil & Environmental Engineering

Surface Water Quality

• water supply

• wastewater discharge

• recreation

Surface Water Quality Management

Add Clark

In A Watershed Everyone Lives Downstream

• water supply

• wastewater discharge

• recreation

Surface Water Quality Management

Temperature and the Density of Water

1.0000

0.9995

0.9990

0.9985

0.9980

0.9975

0.9970

0.9965

0.9960

0.99550.9950

Den

sity

(g∙

cm3 )

0 5 10 15 20 25 30

Temperature (°C)

MaximumDensity3.94 °C

Thermal Stratification

spring summer

Temperature (°C)

Thermal Stratification

Seasonality in Stratification and Mixing

= °C

Dollar Bay - Temperature

0

1

2

3

4

5

6

7 8

Dep

th (

m)

0 5 10 15 20

Temperature (°C)

0

1

2

3

4

5

6

7

8

Dep

th (

m)

M A M J J A S O N D

You are what you eat. For example, there’s this lake …

… and there’s that lake.

Oligotrophic

Low in algae

High transparency

Cold water fishery

Eutrophic

High in algae

Low transparency

Warm water fishery

Trophic State

The Limiting Nutrient Concept

The Supplies

The Product

The Divided Lake

Productivity and Oxygen

Trophic State and Oxygen Profiles

Orthograde

0

2

4

6

8

10

12

14

16

18

20

0 5 10 15 20 25

De

pth

(m

)

Clinograde

0

2

4

6

8

10

12

14

16

18

20

0 5 10 15 20 25

De

pth

(m

)

Oligotrophic Lake Eutrophic Lake

Temperature (°C) Temperature (°C)

Dollar Bay - Temperature

0

1

2

3

4

5

6

7 8

0 5 10 15 20

Temperature (°C)

0

1

2

3

4

5

6

7

8

Dep

th (

m)

M A M J J A S O N D

Dollar Bay – Dissolved Oxygen

Dep

th (

m)

0

1

2

3

4

5

6

7

8

0 2 4 6 8 10 12

Dissolved Oxygen (mg∙L-1)

M A M J J A S O N D

Onondaga Lake – Dissolved Oxygen

Oneida Lake – Dissolved Oxygen

Lake Erie – Dissolved Oxygen

Gulf of Mexico – Dissolved Oxygen

Aerobic and Anaerobic Metabolism

2

3

4

3

24

2

2

2

2

2

2 3

2 2

2 2

2 2

2 2

2 2

2

2

2

42 2

( )

( )

( )

( )

( )

( )

N HCO

M

CO H O

CO H O

CO H O

CO H

O

NO

M

C H O

C H O

C H O

C H O

C H O

C H O

O

CO

n

Fe

H

n

F

S

CH

e

H O

CO

SO

Aerobic (oxygen available)

Anaerobic (oxygen not available)

Oligotrophic

Low in nutrients, TP<10

Low in algae

Oxygen at saturation

High transparency

Cold water fishery

Deep lakes with steep sides and infertile, often rocky watersheds.

Eutrophic

High in nutrients, TP>20

High in algae

Oxygen (+, epi), (-, hyp)

Low transparency

Warm water fishery

Shallow lakes with gently sloping sides and cultivated, fertile watersheds.

Natural Eutrophication

Cultural Eutrophication

Lakes: Loss of Beneficial Use

• Nutrients – aesthetics, recreation, drinking water

• Microorganisms – recreation, drinking water

• Toxics – wildlife, drinking water• heavy metals: cadmium, lead, mercury• synthetic organic chemicals: DDT, PCB, dioxin

Engineering Approaches for Lake Management(Phosphorus)

1. Lake Protection• Point source control (advanced waste treatment)• Nonpoint source control

Engineering Approaches for Lake Management(Phosphorus)

1. Lake Protection• Point source control• Nonpoint source control (land use management)

Engineering Approaches for Lake Management(Phosphorus)

2. Diversion

Onondaga Lake

Seneca River

METRO

Engineering Approaches for Lake Management(Phosphorus)

3. Hypolimnetic Aeration

Support RaftGas Vent

SupportCables

ContactChamber

Air Line &Diffuser

Ballast

Engineering Approaches for Lake Management(Phosphorus)

4. Sediment Inactivation

Engineering Approaches for Lake Management(Phosphorus)

5. Dredging

Engineering Approaches for Lake Management(Phosphorus)

6. Algicides

Engineering Approaches for Lake Management(Phosphorus)

7. Biomanipulation

River Water Quality

Add Clark

In A Watershed Everyone Lives Downstream

Biochemical Oxygen Demand

BOD exerted, y

BOD remaining, L

Dissolved Oxygen Saturation and Deficit

6.0

8.0

10.0

12.0

14.0

16.0

0 5 10 15 20 25 30 35

Temperature (°C)

Dis

solv

ed O

xyg

en (

mg

/L,

pp

m)

Change in oxygen concentration =

inputs from reaeration – losses to deoxygenation

Dissolved Oxygen Sag Curve

Stream Zones and Biota

Organism Diversity and Abundance

top related