Water Quality

and the

Chesapeake Bay

David O’BrienNOAA Fisheries Service

Gloucester Point, VA

Chesapeake Bay

The nation’s largest estuary

Nation’s most biologically diverse estuary;

>3600 species of plants and animals

Over 17 million people live in the watershed

Chesapeake Bay watershedVirginia

Maryland

Pennsylvania

New York

Delaware

West Virginia

Dist. Columbia

What Is a Watershed?

Adapted from NEMO

Water-vapor transport

Ocean

Infiltration

Increased runoff

Decreased

Less groundwaterflow

Lower water table

Evaporation

Evaporation

Less vegetation, thus less Less vegetation, thus less evapotranspiration!!evapotranspiration!!

Increased pollutionIncreased pollution

The Water Cycle

Development: Increased Development: Increased impervious surfaceimpervious surface

Ches Bay Population Growth2010 - 17.2 million

Threats to the Chesapeake Bay

NUTRIENTS

SEDIMENTS

TOXIC CHEMICALS

HABITAT LOSS

OVERFISHING

Chesapeake Bay:

How is it Doing???

Habitat

Conversion

Watershed development

% impervious surface

Water Quality Problems

Algae blooms and sediment cloud the water and block sunlight, causing underwater bay grasses to die.

When the algae die and decompose, they use up oxygen needed by other plants and animals living in the Bay's waters.

Algae blooms and depleted oxygen levels are caused by excessive nutrients

Poor water clarity is caused by algae blooms and suspended sediments

Impaired WatersEPA 303(d) list

Portions of the Chesapeake Bay and its tidal rivers are listed under the Clean Water Act as “impaired waters” largely because of low dissolved oxygen levels and other problems related to nutrient pollution.

This “listing” requires the development of a clean-up plan for the Bay by 2011.

Impaired Water

Note: Representation of 303(d) listed waters for nutrient and/or sediment water quality impairments for illustrative purposes only. For exact 303(d) listings contact EPA (http://www.epa.gov/owow/tmdl/).

Unimpaired Water

Nutrient and/or Sediment Impaired

Harmful Algal Bloom (HAB) Harmful Algal Bloom (HAB) HRBTHRBT

y

HAB Lafayette RiverHAB Lafayette River

Healthy vs. Unhealthy Water Quality

Sunlight Sunlight

HealthyHabitat

UnhealthyHabitat

BalancedAlgae Growth

Minimal nutrient and sediment

inputs

Excessive nutrient and sediment inputs

HealthyBay Grasses Reduced

Bay Grasses

Algae Die-off

Algae Decomposition

No Oxygen

No Benthic Community

Benthic Community

HealthyOyster Reef

AdequateOxygen

Algal Bloom

Barren Oyster Reef

Chesapeake Bay DO 2006-2009

Sources of Pollutants to the Bay

Nonpt. Sources

•Run-off from farmland•Run-off from lawns and

paved areas

Point Sources

•Industry•Wastewater Treatment Plants

Nature of Contaminant Inputs

Point SourceInputs with well defined point of dischargeDischarge is usually continuous

Nonpoint SourceOrigin of discharge is diffuseDischarge may be transient in time

Runoff from croplandEffluent from septic systemsHighway de-icing salts

Leakage from landfills and storage tanksWastewater treatment facilitiesIndustrial inputs

Sediment

Nutrients

Toxic Substances

Pathogens

Non-pointNon-point Source PollutantsSource Pollutants

Hurricane Irene sediment plumeSept. 14, 2011

Nutrient and Sediment Load Reduction Goals

The 2010 pollutant reduction goals are:

Nitrogen - Reduce annual loads to no more than 175 million pounds.

Phosphorus - Reduce annual loads to no more than 12.8 million pounds.

Land-based Sediment - Reduce annual loads to no more than 4.15 million tons.

0

5

10

15

20

25

30

1985 2000 2002*

Pho

spho

rus

Load

(m

illion

lbs/

yr)

2010PhosphorusGoal

0

50

100

150

200

250

300

350

400

1985 2000 2002*

Nitr

ogen

Loa

d (m

illion

lbs/

yr) 2010

NitrogenGoal

0

1

2

3

4

5

6

7

1985 2000 2002*

Sed

imen

t Loa

d (m

illion

tons

/yr) 2010

SedimentGoal

Nitrogen Loading

Phosphorus Loading

Chesapeake Bay Water Quality Goals 2009

Water Clarity

Dissolved Oxygen (DO)

Wetland restoration

Chesapeake Bay Fish / Shellfish Goals 2009

Rockfish Population Stable

Rockfish have rebounded to levels not seen since the 1950’s, but concerns remain over disease, sufficient sources of food and availability of spawning habitat.

0

5

10

15

20

25

30

35

40

4519

8219

8319

8419

8519

8619

8719

8819

8919

9019

9119

9219

9319

9419

9519

9619

9719

9819

9920

0020

0120

0220

03

SS

B (

fem

ales

ag

es 4

+yrs

, mill

ion

s o

f lb

s)

Fishing moratoria:MD & DE: 1985-1990

VA: 1989-1990

Baywide Female Spawning Stock Biomass

Striped Bass

0

5

10

15

20

25

30

35

40

53 58 63 68 73 78 83 88 93 98 2003

Com

mer

cial

Lan

ding

s (m

illio

n lb

s)

Oysters at Historic Lows

VA

MD

Oyster populations in the Chesapeake are at historic lows due to disease, intense harvest pressure and poor water quality.

Oyster stocks

Oyster restoration efforts

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

Sp

aw

nin

g F

em

ale

Ind

ex

Blue Crabs At RiskMature Female Blue Crabs

Average

Blue Crab populations have stabilized at below-average levels.

Improved water quality and habitat restoration efforts along with proper management of the crab harvest are needed to restore the Bay’s blue crab populations.

Blue Crab

Largest crab fishery in the world

$80 million dockside value in Ches Bay

$360 million value to national economy

Blue Crab stock

SAV 2007-2009 goals

Bay Grasses Show Annual Variation

Underwater bay grasses are slowly improving, but further reductions in the pollutants flowing into the Bay are needed to help them flourish.Annual variations in bay grasses show the sensitivity of the Bay ecosystem.

0

20

40

60

80

100

120

140

160

18019

7819

7919

8019

8119

8219

8319

8419

8519

8619

8719

8819

8919

9019

9119

9219

9319

9419

9519

9619

9719

9819

9920

0020

0120

0220

0320

04

Acr

es o

f Bay

Gra

sses

(th

ousa

nds) Restoration Goal (185,000 acres by 2010)

*Note – Hatched area of bar includes estimated additional acreage. No Baywide surveys 1979-83 and 1988 Source: Chesapeake Bay Program.

SAV aerial coverage

PRE-1930’S 1960’S PRESENT

Clam Dredge Scarring in Chincoteague Bay

SAV Restoration - Planting

Special thanks to:

Dr. Bob Orth, VIMS SAV Program

Chesapeake Bay Program

Chesapeake Bay Foundation

NOAA Chesapeake Bay Office

Thanks for your interest!!!