Quartermaster Harbor Nitrogen Management

Study

Project Overview and Preliminary Nitrogen

Loading Estimates to the Harbor

October 25, 2011

Study Team• Jill Gable – Grant Project Officer, EPA• Curtis DeGasperi – Project Manager, KC• Eric Ferguson – Surface/Groundwater

monitor, KC • Kim Stark - Marine monitoring, KC• Cheryl Greengrove – Environmental Science,

UWT• Julie Masura – Researcher, UWT• Skip Albertson – Marine Modeler, Ecology• Larry Stockton –Policy & Public Outreach, KC

Quartermaster Harbor Nitrogen Management Study

• Problem: Low dissolved oxygen levels observed in harbor

• Low oxygen can be harmful to fish and other aquatic life like in South Puget Sound embayments

Quartermaster Harbor

QUARTERMASTER HARBOR

Jan-2006 Jan-2007 Jan-2008 Jan-2009 Jan-2010 Jan-2011

DIS

SO

LV

ED

OX

YG

EN

(M

G L

-1)

0

2

4

6

8

10

12

14

16

18

20MSWH01 NSAJ02 Extraordinary Quality Standard 7 mg L-1

Marine MonitoringMSWH01

NSAJ02

< 1 mg/L

Yacht Club Mooring September 2008

http://green.kingcounty.gov/marine-buoy/

15-minute data - September 20 – 22, 2008

Quartermaster Harbor Nitrogen Management Study

Goal: Determine how human activities (along with natural factors) affect low dissolved oxygen levels in Quartermaster Harbor

www.kingcounty.gov/QMHnitrogenstudy

Sources of Nitrogen on VMI

• Atmosphere• Septics• Livestock• Fertilizer• Alder• Boats

Sources of Nitrogen to Quartermaster Harbor

Harbor

Atmosphere

Marine Boundary

Streams

Groundwater

Sediment

Nearshore Septics

Boats

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

Nitr

ate+

Nitr

ite-N

(m

g/L)

0

2

4

6

8

10

Streams Sampling Locations

Judd Creek

Mileta Creek

Fisher Creek

Marine Monitoring Stations

King County UWT

Mooring

Septic SystemLocations

Nitrate in Shallow Groundwater

Median (mg NO3-N/L)

0.1 - 0.55

0.55 - 1.1

1.1 - 2.3

2.3 - 3.93

3.93 - 6.5

CARA CODE

1

2

3

Shallow Deep

Nitr

ate

Nitr

og

en

(m

g/L

)

0

2

4

6

8

• Marine boundary• Boats

External N inputs not assessed

Nearshore Septic

Systems25%

Submarine Groundwater

10%Surface Streams

59%

Atmospheric Flux6%

July – October Estimates

Nearshore Septic

Systems50%

Submarine Groundwater

20%

Surface Streams

23%

Atmospheric Flux7%

kg N

pe

r da

y

0

10

20

30

40

50

60

70

Uncertainty in Nitrogen Loading

Estimates

NearshoreSeptics

AtmosphericDeposition

Groundwater

Streams

Benthic Flux StudySeptember 1-2, 2010

0

50

100

150

200

250

300

350

400

450

500

Nearshore Septic

Systems

Submarine Groundwater

Surface Streams

Atmospheric Flux

Benthic Flux

KG N

PER

DAY

Nitrogen Loading Estimates

Seasonal Load (late summer)?

Generalized Environmental Modeling System for Surfacewaters (GEMSS®)

“Wicked” Problem

• No silver bullet• Multiple nitrogen

sources• Puget Sound wide

perspective forthcoming

Questions?

Curtis DeGasperiKing County Water and Land Resources

(206) 684-1268curtis.degasperi@kingcounty.gov