tom jordan - smithsonian institution

Tom Jordan

City Stream, Country Stream:Getting a Clearer Picture of Stream Restoration

Smithsonian EnvironmentalResearch Center

Urban Stream Syndrome

“Restoration?”• What:

• Restoring function, not pre-impact condition

• Why:• Stop erosion caused by urban runoff• Reconnect the stream with its floodplain• Control flooding downstream• Improve stream habitats• And…

Main Motivation=

Reduce discharges of:

nitrogen, phosphorus, and suspended solids

Nitrogen and Phosphorus

• Essential nutrients for all living things

• Often limit growth of plants and algae

• Cycles greatly altered by human activities

• Overloading coastal waters worldwide

In Chesapeake BayExcess nutrients and sediments have caused: • Algal blooms• Low dissolved oxygen• Loss of submerged aquatic vegetation• Food web disruption

Reductions in nitrogen, phosphorus, and sediment loads to the Chesapeake are now mandated by an EPA “Total Maximum Daily Load pollution diet.”

Can Stream Restorations Help?

• Studies show variable but potentially significant improvements in nutrient reduction.*

• Restoration approaches differ

• Streams differ

• Long-term effectiveness is not known

*e.g. Filoso et al. 2015, Filoso and Palmer 2011, Williams et al. 2017, Cizek et al. 2017

Muddy Creek Restoration

Before…

Watershed, 226 ha• 49% Forest• 21% Pasture & Hay• 14% Fallow• 14% Residential• 2% Row Crops

Muddy Creek Restoration

Watershed, 226 ha• 49% Forest• 21% Pasture & Hay• 14% Fallow• 14% Residential• 2% Row CropsSand Plus

Woodchips

RSC: Regenerative Stormwater Conveyance

Gravel

Installing weir at outlet of Muddy Creek RSC

Provided by:Underwood & Associates

The weir and automated sampler at the outlet of the restored reach

A Pool in Muddy Creek After Restoration

A Riffle and a Berm in Muddy Creek After Restoration

Automated Sampler and Sondes

Automated Sampler and Sondes

Groundwater Sampling Transects

Map by Underwood & Associates

• Flow-paced sampling (e.g. 30-60 water samples per week).

• Water samples composited for a weekly mean concentration.

• Concentration X weekly water flow = Weekly load.

Thompson et al. 2018. The multiscale effects of stream restoration on water quality. Supplementary Data. Ecological Engineering 124:7-18.

Muddy Creek Watershed

450 mRSC

Muddy Creek Watershed=Treatment

RSC

Bluejay Branch=Control

Concentration X Water Flow = Load

Load in – Load Out = Amount Removed

% Removed = (Amount Removed / Load In) X 100

Calculating Nutrient Removal

-40

-20

0

20

40

60

80BeforeAfter

Total P

Comparing the inlet and outlet of the restored reach:Percentage of inflow removed increased after restoration

PO4 NH4 Total NNO3 TSS

p<0.05 p<0.05 p<0.1 p<0.1

Statistical Test: Randomized Intervention Analysis

Tota

l Rem

oval

(%)

Thompson et al. 2018. The multiscale effects of stream restoration on water quality. Ecological Engineering 124:7-18.

Muddy Creek Watershed=Treatment

RSC

Bluejay Branch=Control

Comparing the treatment and control watersheds:No statistically significant changes in loads could be attributed to the restoration.The effects may have been masked by the effects of beaver ponds downstream of the restoration (Thompson et al. 2018. Ecological Engineering 124:7-18).

Dissolved Oxygen Concentration at Inlet and Outlet

Note: Data here and elsewhere in this presentation are unpublished and should be considered preliminary unless a specific publication is cited.

Dissolved Oxygen profile of Muddy Creek on July 19th 2016

Dissolved Oxygen profile of Muddy Creek on July 19th 2016

Flow direction

0

2

4

6

0 200 400 600

DO

(mg/

L)

Meters Away from Muddy Creek Road

Dissolved Oxygen in Muddy Creek

Transect of Wells and Piezometers

Before restoration, the eroded channel drained the banks.

Clay Aquiclude

Well Piezometers

Clay Aquiclude

Well Piezometers

Sand & Woodchips

Gravel

After restoration, the water table elevation increased.

Sand Filter Concept:

-The gravel layer allows faster groundwater flow than the overlying sand.

-This pulls water downward through the sand.

-At the end of the restored reach groundwater carried through the gravel is released back into the surface flow.

Sand and Woodchips

Stream Water Surface

Changes in Groundwater after Restoration

Decreased:

PhosphateAmmoniumSulfatepH

Increased:

Organic CIronOxygenConductivity

No change:

Nitrate

SPSC

0.00.20.40.60.81.01.21.41.61.82.02.2

6/28/16 7/3/16 7/8/16 7/13/16 7/18/16

Stag

e Fe

et

Stage at Harbour Center RSC Inlet

0.8

1

1.2

1.4

1.6

1.8

2

2.2

2.4

6/28/16 7/3/16 7/8/16 7/13/16 7/18/16

Stag

e Fe

et

Stage at Muddy Creek RSC Inlet

1 2 3 4 56

Harbour Center: Step Pool Stormwater Conveyance

AS

ASAutomated Samplers

Design and Plans:Environmental Systems Analysis, Inc.Bay Engineering, Inc.Provided by South River Federation

StormwaterRetention

Pond

Upstream End of Harbour Center SPSCAutomated Sampler

Rock Weirs Along Harbour Center SPSC

Automated Sampler at the downstream end of the Harbour Center SPSC

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

20-Feb-16 19-Jul-16 16-Dec-16 15-May-17 12-Oct-17 11-Mar-18 8-Aug-18

inlet

outlet

Nitrate plus Nitrite (mg N/L) at inlet and outlet of SPSCN

O3-

plus

NO

2-(m

g N

/L)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

20-Feb-16 19-Jul-16 16-Dec-16 15-May-17 12-Oct-17 11-Mar-18 8-Aug-18

inlet

outlet

NO3 in Rain: Minimum

Nitrate plus Nitrite (mg N/L) at inlet and outlet of SPSCN

O3-

plus

NO

2-(m

g N

/L) NO3 in Rain: Maximum

NO3 in Rain: Mean

70% of the Nitrate plus Nitrite was removed

Other Nutrient Forms and Suspended Solids Were Not Removed

• Ammonium Nitrogen• Organic Nitrogen• Total Nitrogen (including 12% Nitrate plus Nitrite)• Phosphate• Total Phosphorus• Total Suspended Solids

SPSC

0.0

0.2

0.4

0.6

0.8

9/22/17 12/31/17 4/10/18 7/19/18 10/27/18 2/4/19 5/15/19

Nitr

ate

mg

N/L

Nitrate mg N/L

NO3

Concentrations in Church Creek downstream of Route 2 (station 4)

0.0

0.2

0.4

0.6

0.8

9/22/17 12/31/17 4/10/18 7/19/18 10/27/18 2/4/19 5/15/19

Nitr

ate

mg

N/L

Nitrate mg N/L

NO3

Concentrations in Church Creek downstream of Route 2 (station 4)

0.0

0.2

0.4

0.6

0.8

9/22/17 12/31/17 4/10/18 7/19/18 10/27/18 2/4/19 5/15/19

NO

3 an

d N

H4 m

g N

/L

Nitrate and Ammonium (mg N/L)

NO3

NH4

Concentrations in Church Creek downstream of Route 2 (station 4)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

9/22/17 12/31/17 4/10/18 7/19/18 10/27/18 2/4/19 5/15/19

NO

3, N

H4, a

nd O

rgan

ic N

(mg

N/L

)

Nitrate, Ammonium, and Organic N (mgN/L)

NO3

NH4

Org N

Where does the nitrate go?

• Converted to nitrogen gas by denitrification and released to the atmosphere.

• Converted to organic nitrogen and held in the stream.

• Converted to organic nitrogen and carried downstream.

0

2

4

6

8

10

12

14

16

18

0 20 40 60 80 100

Percentage of Cropland

Annual Flow-Weighted Mean Nitrate Concentrations

Conestoga R.Lancaster Co. PA

North of Baltimore

Central PA

E. and W. ShoresUrban Streams

00.20.40.60.8

11.21.4

nh4 nh4

MCr Harb

Ammonium

Series1 Series2

00.20.4

no3 no3

MCr Harb

Nitrate

Series1 Series2

0

1

2

3

4

5

6

TN TN

MCr Harb

Total N

Series1 Series2

Muddy Cr Harbour Muddy Cr Harbour Muddy Cr Harbour

Inlet

Outlet

Comparing average concentrations at the inlets and outlets of the two restored stream reaches.

Data for Muddy Creek are from Thompson et al. 2018. Ecological Engineering 124:7-18Data for the Harbour Center SPSC are unpublished.

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

PO4 PO4

MCr Harb

Series1 Series2

0

0.1

0.2

0.3

0.4

0.5

0.6

TP TP

MCr Harb

Series1 Series2

0

50

100

150

200

250

TSS TSS

MCr Harb

Series1 Series2

Muddy Cr Harbour Muddy Cr Harbour Muddy Cr Harbour

Phosphate (mg P/L)Total P mg/L

Total Suspended Solidsmg/L

Comparing average concentrations at the inlets and outlets of the two restored stream reaches.

Inlet

Outlet

Data for Muddy Creek are from Thompson et al. 2018. Ecological Engineering 124:7-18Data for the Harbour Center SPSC are unpublished.

The City Stream

• Urban SPSC retained about 70% of the nitrate input.

• SPSC effects uncertain without preconstruction data.

• Low concentrations in the summer suggest biological uptake in the streams and SPSCs.

• Nitrate concentrations in urban streams were low compared to rainfall and agricultural watersheds.

The Country Stream

• The Muddy Creek RSC removed high percentages of phosphate, total phosphorus, ammonium, total N, and total suspended solids (TSS)

• But the changes in removal rates of TN and TSS after restoration were not statistically significant.

Parting Thoughts…Before restoring streams to remove nutrients maybe one should:

-Measure the nutrient concentrations-Consider ways to reduce the sources

Runoff from impervious surfaces is very destructive to stream ecosystems.

Deicing salts and other substances pollute urban runoff and should be managed.

The SERC Researchers:• Co-Investigator: Cynthia Gilmour

• Postdocs: William Brogan III and Joshua Thompson

• Technicians: Carey Pelc, Max Ruehrmund, Sean Hartnett, Emily O’Gwin, Tyler Bell, Shannon Insley, Ana Morales, Denise Butera, Will McBurney, and Patricia Dubyoski

• Interns: Julianne Rolf, Jan Kreibich, Brendan Player, Lauren Mosesso, Emily O’Gwin, Christina Klein, and Calvin Parker

• Citizen Science Volunteers: Joe Miklas, Ed Ambrogio, Sue Zeisler, and Keidra Douglas

Partners:

South River Federation(Now the Arundel Rivers Federation)

Sarah GiordanoJesse IliffWayne MartinDianna Muller Kate Fritz

We thank these organizations for support:

Rathmann Family Foundation