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