loiss: tsc workshop 2013 coastal processes · 2014. 1. 24. · cohesive bluff adjacent armourstone...

LOISS: TSC WORKSHOP 2013

Coastal Processes

COASTAL PROCESSES: BACKGROUND

• Background Review And Data Gap Analysis: Coastal Processes (ShorePlan, 2011)

• Shoreline Recession Monitoring Program (Geomorphic Solutions, 2011 and 2012)


Data gaps identified by Shoreplan (LOISS Background Study)

Potential Actions

• Effects of waves on nearshore currents at a specific location

• Influence of proposed shoreline modifications on littoral sediment regime

• Influence of proposed shoreline modifications on sub-littoral sediment regime

• Condition and extent of shoreline protection structures (private and public lands)


Background Information Available• Bathymetry

• NOAA lake-wide bathymetry, errors observed• Local CHS surveys• Topographic Transects (GS, 2012)• Limited nearshore detail

• Wave Climate• 40 years of hourly offshore hindcasts for wave height (WIS)• Dominant and prevailing waves from the east

• Littoral Drift• Generally non-drift due to lack of sediments• Net transport for majority of the study area assumed to be fromnortheast to southwest

• Water Level• 100 year Data from 3 Stations• 75.59m Mean Monthly Water Level

Coastal Processes: 2010


Shoreline Type Length (m)% of Total

Length

all reaches 20,145

artificial shoreline 9,003 45%

cohesive shore with protection structure 7,779 39%

cobble beach 1,454 7%

sand beach 834 4%

cohesive shore with protective beach or rubble 799 4%

unprotected cohesive bank or bluff 276 1%

GENERAL SHORELINE STATISTICS


Shoreline Protection Type Length (m)% of Total

Length

revetment 6,072 30%

wall 4,332 22%

beach 3,495 18%

wall and revetment 2,924 15%

rubble 1,417 7%

headland-beach (artificial) 904 4%

none 858 4%

rip-rap berm 143 < 1%

GENERAL SHORELINE PROTECTION STATISTICS

Coastal Processes: 2011Shoreline Recession Monitoring Program Identify field monitoring sites


Site ID Location Shoreline Type Shore Protection1 Fusion Park cohesive bluff adjacent pier

2 Lakeside Park non-cohesive bluff adjacent piers; clay pipe debris

3 Watersedge Park sea wall with fronting beach armourstone sea wall

4 Rattray Conservation Area dynamic beach barrier* none

5 Jack Darling Memorial Park dynamic beach low plain* boulders on backshore;

adjacent groynes

6 Richard Memorial Park dynamic beach low plain* adjacent groynes

7 Rhododendren Garden cohesive bluff adjacent armourstone toe

protection 8 JC Saddington Park boulder revetment boulder revetment

9 Tall Oaks Park non-cohesive low plain armourstone on

backshore; adjacent groyne

10 Hiawatha Park boulder revetment boulder revetment

11 The Adamson Estate

sea wall armourstone sea wall; adjacent armoured headland

12 RK McMillan dynamic beach low plain* adjacent armoured headland

Shoreline Recession Monitoring Program Identify field monitoring sites

Coastal Processes: 2011Shoreline Recession Monitoring Program Characterize field monitoring sites

Site ID

Location CameraDepth (m)

Bed Composition Photograph

1 Fusion Park 0

Sand ripples

0.7 Bedrock, few boulders

4.2 Bedrock, few boulders

Coastal Processes: 2011Shoreline Recession Monitoring ProgramHistorical aerial photographic assessment


Shoreline Recession Monitoring ProgramPhotogrammetric analysis of shoreline recession rates

Coastal Processes: 2011Shoreline Recession Monitoring ProgramPhotogrammetric analysis of shoreline recession rates

Fusion Park

Measurement Location

Recession Rate (m/yr) 1931-1946 1946-1954 1954-1978 1978-2009 1931-2009

A 0.31 1.40 0.05 0.22 0.30 B 0.25 1.14 0.16 0.30 0.33C 0 1.09 0.25 0.24 0.29

Average 0.19 1.21 0.15 0.25 0.31

OPG Piers Measurement

Location Recession Rate (m/yr)

1931-1946 1946-1954 1931-1954 A 1.27 0.08 0.85 B 0.39 0.43 0.40 C 0.21 0.89 0.45D 0.03 1.03 0.38 E 0.11 0.62 0.29 F 0.14 0 0.07 G 0.15 0 0.06 H 0.07 0.25 0.13I 0.08 1.00 0.40 J 0 0.78 0.24

Average 0.25 0.51 0.33


Shoreline Recession Monitoring Program (Recommendations from Geomorphic Solutions)

• Aerial photogrammetric studies not as accurate as the ground surveys

• Recommend aerial photogrammetric assessment every 10 yrs at locations where the shoreline is not fully protected

• Collect yearly aerial photographs. Digital aerial photographs of the CVC shoreline are generally commercially flown every year

• Consider water penetrating LiDAR surveys in partnership with other agencies only if cost effective


Coastal Modeling for Water Quality Analysis

Coastal Processes: 2012Coastal Modeling for Wave ParametersCurrent & Hydrodynamic


Coastal Modeling for Wave ParametersCurrent & Hydrodynamic

Coastal Processes: 2012Coastal Modeling for Wave ParametersCurrent & Hydrodynamic

Coastal Processes

Data & Knowledge Gaps

Inventory of shoreline structures: georeferenced location,structure type (revetment, seawall, armourstone blocks,dimensions,

photo inventory etc) An assessment of shoreline structure condition Establish Long term survey lines for long term monitoring Analysis for shoreline naturalization as per LOISS goals Determine nearshore wave parameters, current and hydrodynamic

COASTAL PROCESSES: PROPOSED NEXT STEPS

Incorporate Coastal Shoreline Monitoring Protocol into monitoring program

Inventory and assess public protection structures: RFP ISSUED

Erosion monitoring: COMPLETED FOR 2012

Aerial photos: Annual

LiDAR Survey: water penetrating

Seasonal fluctuations as station survey spring/summer/storm events

QUESTIONS?

LOISS: TSC WORKSHOP 2013COASTAL PROCESSES: BACKGROUNDCOASTAL PROCESSES: BACKGROUNDCOASTAL PROCESSES: BACKGROUNDCoastal Processes: 2010Coastal Processes: 2010Coastal Processes: 2010Coastal Processes: 2011Coastal Processes: 2011Coastal Processes: 2011Coastal Processes: 2011Coastal Processes: 2011Coastal Processes: 2011Coastal Processes: 2011Coastal Processes: 2012Coastal Processes: 2012Coastal Processes: 2012Coastal Processes: 2012Coastal ProcessesCOASTAL PROCESSES: PROPOSED NEXT STEPSQUESTIONS?

loiss: tsc workshop 2013 coastal processes · 2014. 1. 24. · cohesive bluff adjacent armourstone...

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