Environment Commission of the Central Dredging Association (CEDA)Marine Systems Institute at Tallinn University of Technology (MSI)

International seminar "Dredging and the Environment“Tallinn, 15-16 October 2008

Results of the environmental monitoring of the recent expansion of Port of Tallinn

Jüri Elken, Marine Systems Institute, Tallinn University of Technology, Estonia

Overview based on a large number of individual contributors

main institutions:Marine Systems Institute, Tallinn University of TechnologyEstonian Marine Institute, University of Tartu

Muuga

Veere

Paldiski

Kunda

Kuressaare

Lehtma

Haapsalu

Tallinn

Narva

PärnuVirtsu

Coastal sea research areasPermanent areas (harbors)

Projects

River mouthPulp mill

Sewage

Ice Dredging

Dredging

Dredging

New harbor

Harbours in N & NW Estonia

Port developments include several environmental risk issues. According to Estonian environmental law the environmental impact assessment (EIA) is compulsory if the amount of dredging or dumping during the construction is more than 10 000m3 of sediments.

The normal EIA in case of harbor development expands upon the following possible environmental impacts:

•Heavy metals and oil products in sediments•Meteorological conditions (winds)•Hydrodynamical conditions (water level, waves, currents)•Marine biota (bottom fauna, bottom flora, fish, birds) •And socio-economical impacts.

After the EIA is accepted by the Ministry of Environment the necessary environmental monitoring program is worked out for every case. The most important part of monitoring program is monitoring the impact tomarine environment during the dredging.

Wintering of globally endangered Steller’s Eider

From report by Kuresoo et al.

Observations near Tagamõisa peninsula, NW Saaremaa

Tarmo Kõuts, Janek Laanearu

Spatial probability of oil pollutionEIA-related study of planned deep harbor sites, NW Saaremaa

Method:• calculate currents for long (≈year) period, that it covers basic wind statistics• release drifters from point source every Lagrangian time step• recollect drifter positions after specified inetrval (24 h)• average “final positions” over entire calculation periodMotivation, social alarm due to:• nearby nature reserve (Vilsandi National Park)• wintering places for globally endangered birds

Jüri Elken

New Saaremaa Harbour, operational since 2006

New Saaremaa Harbour, monitoring of coastal processes / damages

Results from 2006-2008:

Coastal changes correspond to the stormy periods with high waves, influence of port structures on natural coastal dynamics was not identified

Jüri Kask, Andres Kask

New Saaremaa Harbour, measurements of wave activity

wind speed

measurements in October 2007 near harbour

wind direction

significant wave height

Results are used also for adjustment and verification of wave models, necessary for calculation of sediment transport, oil drift etc

Modelling showed that SWAN model derived significant wave heights were well correlated with the measured ones, whereas model overpredicted small wave events and underpredictedsignificant wave events. The wave climate of the bay is rather mild and the highest waves are expected during north-westerly storms.

Tarmo Kõuts, Kaimo Vahter, Victor Alari

New Saaremaa Harbour, measurements of currents

measurements in October 2007 near harbour

measurements in July 2007 near harbour

Tarmo Kõuts, Kaimo Vahter, Victor Alari

Currents are small, but important for spreading of accidental pollution to sensitive areas

New Saaremaa Harbour, monitoring of phytobenthos

Georg Martin et al

results from 2007sampling grid

species dependence on depth

Fraction of one-year species has been persistent over longer time. Effects of harbour could not been identified.

New Saaremaa Harbour, monitoring of zoobenthos

Mean number of species

Mean number of species by groups: III – pollution sensitive

ANOSIM tests show, that changes are random/natural.

Effects of harbour could not been identified.

Jonne Kotta et al

New Saaremaa Harbour, monitoring of fish

Mean catches of herring (Räim), flounder (Lest), cod (Tursk) and other fishes (Muud)

Ahto Järvik, Toomas Saat et al

Flounder catches have been stable. Herring catches have been influenced mainly by interannual weather variations.

Harbour Old City Harbour

Muuga Harbour

Paljassaare Harbour

Paldiski South

Harbour

Saaremaa Harbour

ϕ=59°27′N ϕ= 59°30′N ϕ=59°27′N ϕ=59°20′N ϕ=58°32,4′Nλ=24°46′E λ =24°58′E λ=24°42′E λ=24°05′E λ=22°14,4′E

Harbour territory (ha) 54,2 524,2 43,6 114,7 10,08Harbour aquatory (ha) 75,9 752,0 35,5 137,2 44,3

Canal Width (m) none none 90 - 150 90 - 150 noneCanal Depth (m) none none 9,0 14,0 none

No. of quays 23 28 11 8 3Total length of quays (m) 4166,5 5900 1859 1442,5 445

Max. depth (m) 10,7 18,0 9,0 13,5 10,0Max Length of vessels (m) 320 300 190 230 200

Max Width of vessels (m) 40 48 30 35 30

Port of Tallinn comprises:

Vanasadam (Old City Harbour)Muuga HarbourPaljassaare HarbourPaldiski South HarbourSaaremaa Harbour

Location

Port of Tallinn: harbours and their expansions

cargo cargo

Muuga Harbour 2001

Muuga Harbour 2007

Muuga Harbour: planned extensions

present

Paldiski South Harbour 2007

Paldiski South Harbour: present scheme and planned extensions

Transect 1 (1.5 km to East)

Transect 2 (1.5 km to West)

67 7

53

54 3

7 7 5

0

1

2

3

4

5

6

7

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007Aasta

Liikide arv (Transekt 1)

1312 13

8

56

9

78 8 8

0

1

2

3

4

5

6

7

8

9

10

11

12

13

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007Aasta

Liikide arv (transekt 2)

Results 2007

Number of species 1997-2007

• Species composition has somewhat changed.Number of species has been stable.

• Due to increased transparency, phytobenthos spreads down to 12 m depth.

• Increase of diversity in 2005-2006 was not persistent

• Clay-hoggin sediment was replaced by sandy substrates

Muuga Harbour: phytobenthos

Georg Martin, Natalia Savinitš et al

20

105

Muuga laht

Macoma balthica ja Mytilus trossuluss biomasside muutused sügavustel 5-30 m

0

100

200

300

400

500

600

700

800

900

1996 1997 1998 1999 2001 2002 2003 2004 2005 2006 2007aasta

biom

ass

Mytilus trossulusMacoma balthica

Macoma balthica ja Mytilus trossulus arvukuse muutused sügavustel 5-30 m

0

1000

2000

3000

4000

5000

6000

1996 1997 1998 1999 2001 2002 2003 2004 2005 2006 2007

aasta

arvu

kus

Macoma balthicaMytilus trossulus

Vähilaadsete arvukuste muutused sügavustel 5-30 m

0

100

200

300

400

500

600

700

800

1994 1996 1998 2000 2002 2004 2006 2008aasta

arvu

kus

is/m

2

Water quality has improved since 1990s:

• Macoma balthica ja Mytilus trossulusbiomass and abundance had decreased

• crayfish abundance has increased

Muuga Harbour: zoobenthos

biomass

abundance

Ilmar Kotta, Jonne Kotta, Helen Orav et al

• To the West, in Tammneeme region, water quality has decreased

• To the East, fish populations are decreasing

• Fish stocks have decreased in the extended harbor aquatory

• Further to the East, the influence of harbour is not significant

2007

Meritint; 2

Viidikas; 4

Ahven ; 27

Kiisk; 1

Vimb; 2

Lest; 15

Räim; 5Nurg; 1 Räim

Lest

Meritint

Ahven

Kiisk

Vimb

Viidikas

Nurg

Fish species

Teised ViidikasSärg

Räim

Meritint

Lest

Ahven

0%

20%

40%

60%

80%

100%

1999 2000 2001 2002 2003 2004 2005 2006 2007

Ahven

Lest

Külmaveelised

Teised

0%

20%

40%

60%

80%

100%

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

E monitoring

NW monitoring

Dynamics and structure of fish catches

Muuga Harbour: fish

Flounder

FlounderFlounder

Perch

Perch

Ahto Järvik, Robert Aps et al

Randvere region• stable

Saviranna region• small replacements of fine sediments

Jüri Kask, Andres Kask

Muuga Harbour: coastal dynamics

Historical current mapping 1975-1989altogether 518 measurements, incl 397 measurements in surface layer 0-10 m,

Current measurements

Buoy4 months

1996

Validation of model: daily mean currents

Southerly winds Northerly winds

Westerly winds Easterly winds

Oil pollution by tanker “Alambra”, september 2000

18.09.2000 12:00

20.09.2000 00:0019.09.2000 12:00

19.09.2000 00:00

Observed coastal

pollution

Spatial probability of oil pollutionMuuga harbour

Control of environmental effects of dredging operations

Paldiski Harbour, 2002-2003

Tarmo Kõuts, Urmas Raudsepp, Liis Sipelgas et al

Daily amounts of dredged material

Total amount ofdredged material1 705 799 m3

sand, silt, clay

Sediment examples

Marine Systems Institute has long time expertise for port dredging and construction monitoring.

During dredging activities coastal waters receive considerable amount of suspended material. The sea area affected by resuspended sediments depend on the amount of matter released in the water and the transport by currents.

For continuous monitoring of distribution of suspended sediments during the dredging activities we have used combination of:

Remote sensing, numerical modelling and in situ measurements

Remote sensingSeveral optical remote sensing sensors (MODIS, MERIS) provide satellite images over Baltic Sea every day. Such high temporal resolution is necessary of continuous monitoring. In our work we have used MODIS images with spatial resolution of 250 meters what are converted into suspended matter concentration according to our calibration algorithm.

Numerical modelingHydrodynamical and particle transport model is used continuously during the construction period for calculation of SPM distribution.

In situ measurements During the dredging also surveys of water transparency, temperature and salinity along with taking water samples from the surface layer are performed. Concentrations of suspended matter are determined by laboratory analyses of the water samples.

Satellite images give the SM distribution on cloud free days; particle transport model is used to evaluate the situation on cloudy days and also can be used to give a forecast for SM distribution. Results of operational monitoring provide data for assessment of harbor dredging impact on marine biota.

2D model+ particle tracking

grid step 125 m

Main problem:

sediment cloud

should not move to the sensitive

fish spawning areasin the south

mg/L

Example of the method, dredging of Paldiski South Harbour in 2002/2003

Suspended matter distribution Model result SPM concentration estimated

from MODIS image

Winds form the northern directions, April 25, 2003

Winds form the southern directions, May 11, 2003

Dredgingsite

Modeling gives opportunity also to calculate the SPM distribution forecast

Forecast of suspended matter distribution by the model;an example of 12 hours forecast

Forecast 18.05.2003; 12.00 Hindcast 18.05.2003; 12.00

Exceptional permit was given: operational monitoring and forecast system had to give warnings if fish spawning damage could occur

Current work in Paldiski South Harbour

23.94 23.96 23.98 24 24.02 24.04 24.06 24.08 24.1 24.12 24.1459.25

59.3

59.35

59.42

0.8

53.2

2932.42

1.61.811.2

1.41.61.2

0.50.91.31.72.12.52.93.33.74.14.54.95.35.76.16.56.97.37.729

5.September 2008, SPM (mg/L) fromwater samples

23.94 23.96 23.98 24 24.02 24.04 24.06 24.08 24.1 24.12 24.1459.25

59.3

59.35

59.41.6

2

3.61.8

3.81.83.62.8

1.821.61.6

4.22.22.6

0.50.91.31.72.12.52.93.33.74.14.54.95.35.76.16.56.97.37.7

28.August 2008, SPM (mg/L) from watersamples

SPM concentration raised from 3mg/L to 30 mg/L within a week indredging area

Dredgingsite

Monitoring of sand mining from Muuga Bay.For Muuga harbor expansion the sand mine was opened in the sea. The expensive mining caused high

SPM concentration in surrounding water and it was well seen on MODIS images.

6. Sept 2003, before mining 20. Sept 2003, beginning of mining

1. Oct 2003, mining period SPM concentration up to 30-40 mg/L inred area

10. Oct 2003, mining periodSPM concentration up to 30-40 mg/L in red area

Liis Sipelgas

Spreading of suspended matter near the Prangli sand mining site1. October 2003

Andres Kask