hydrography – monitoring surveys along the shoreline ...€¦ · malcolm bowdidge 51. st . marine...
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Hydrography – Monitoring surveys along the shoreline
Malcolm Bowdidge
51st Marine Measurement ForumSouthampton, 5th December 2012
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Monitoring surveys along the shoreline
Introduction
Hydrography
Mitigation survey - Lymington:
Project
Method
Problems
Results
Mitigation and Research survey – Wallasea:
Project
Research
Investigation survey – Bristol Channel:
Project
Investigation
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Monitoring surveys along the shoreline
Introduction
Leading UK Marine Environmental Consultancy
Extensive track record (circa 60 years) in leading & contributing to environmental studies across a wide range of industries
Work for Government and its Agencies, across many sectors including Ports, Coastal Management, Policy & Planning and Energy
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Monitoring surveys along the shoreline
Introduction
ABPmer structured into four specialist teams:
Modelling
Processes (Coastal)
Environment
Data Management
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Monitoring surveys along the shoreline
Hydrography:
is broadly defined as
"the measurement and description of the features of the sea and coastal areas for the primary purpose of navigation and all other marine purposes and activities".
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Monitoring surveys along the shoreline
Lymington
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Monitoring surveys along the shoreline
Lymington – Project
Following the introduction of larger ferries on the Lymington to Yarmouth
( IOW ) there was a request to monitor the mudflats to see if any adverse effects would be seen.
A location was chosen where at peak times two ferries passed and there are two relatively sharp turns where extra propulsion would be required.
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Monitoring surveys along the shoreline
Lymington – Project
Monitoring was to be carried out on a monthly basis and to millimetric accuracy.
Health and safety issues with regard to access.
Bathymetric survey
LiDAR
Laser scanning
Levelling
Another
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Monitoring surveys along the shoreline
Lymington – Method
As the stakes were to be placed in the mud flats, 12mm diameter plastic tubing one metre in length, was used to alleviate any damage to yacht’s should they hit any pipe.
A graduated scale was printed on gummed plastic sheets and these were secured onto the pipes. Electrical tape being used to mark individual pipes.
Monthly visit to take photographs taken from a rib.
Measurement taken from photograph.
Comparison and analysis carried out.
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Monitoring surveys along the shoreline
Lymington – Problems
Daylight – spring low water required
Tide levels – metrological effects
Weed growth
Scour
-40
-30
-20
-10
0
10
20
30
40
50
CB1 CB2 CB3 CB4 CB5 CB6 CB7 CB8 CB9 CB10 TB1 TB2 CH1 CH2 SP1 SP2 SP3 SP4 SP5 SP6 SP7 SP8 SP9 SP10
Cha
nge in heigh
t (mm) Survey 2
Survey 3Survey 4
Survey 5Survey 6Survey 7
x
x = unable to assess change in substratum height due to water covering base of stake and/or seaweed obscuring scale. Note, stakes deployed on Survey 1.
x x x x x x xx x
Lymington – Results
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Monitoring surveys along the shoreline
Wallasea
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Monitoring surveys along the shoreline
Wallasea – Project
Compensation for harbour works
Environmental Impact Assessment ( EIA )
Monitoring survey
Research
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Monitoring surveys along the shoreline
Wallasea – EIA
Bathymetric survey
Current monitoring
Breach Design
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Monitoring surveys along the shoreline
Wallasea – Monitoring
Breach monitoring
Sampling
DGPS levelling
Bathymetric
Lidar
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Monitoring surveys along the shoreline
Wallasea – Research
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Monitoring surveys along the shoreline
Wallasea – Research
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Monitoring surveys along the shoreline
Wallasea – Research
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Monitoring surveys along the shoreline
Wallasea – Research
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Monitoring surveys along the shoreline
Bristol Channel
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Monitoring surveys along the shoreline
Bristol Channel – Project
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Monitoring surveys along the shoreline
Bristol Channel – Project
• Walk the coastline from Sharpness to Porlock• Nominal One kilometre spacing
Investigate type / size of material and take photographs• Area fronting sand dunes required further investigations down to MLWS
Investigate type / size of material in sand dunes
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Monitoring surveys along the shoreline
Bristol Channel – Investigation
Sampling by sheet coring and hand cores at MHW
Sampling by hand cores using hovercraft at sand / clay interface
Day grabs at the MLWS
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Monitoring surveys along the shoreline
Bristol Channel – Investigation
• Sheet cores• Hovercraft
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Monitoring surveys along the shoreline
Bristol Channel – Investigation
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Monitoring surveys along the shoreline
Bristol Channel – Investigation
Report
Particle Size Analysis
PSA data was feed in to client’s system
Distribution of materials
Dune replenishment
PDF activated spread sheet
