MAMQUAM BLIND CHANNEL INTEGRATED WATERHED MANAGEMENT PLAN HAY & - - PowerPoint PPT Presentation

MAMQUAM BLIND CHANNEL INTEGRATED WATERHED MANAGEMENT PLAN

HAY & COMPANY CONSULTANTS

• Dr. Adrian Chantler, P.Eng.

Maria Lau, M.Eng., E.I.T.

DISTRICT OF SQUAMISH

Ministry of Environment Dyke Inventory Map District of Squamish Mamquam River and Squamish River flowed Through area until 1920s

• 1921 Flood
• Dyking System

Rewatering is desired

2001 Hayco Rewatering Design 2001 Hayco Rewatering Design

To improve tidal-flushing:

Channel improvement of Wilson Slough Culvert improvement at Buckley Ave. Culvert improvement at Loggers Lane

Mamquam Reunion Mamquam Reunion

To reconnect flows from the Mamquam River back

into the MBC

Brennan Channel: installation of a steel intake

structure and pipeline that now delivers water into a stable rehabilitated side channel providing off-channel habitat

Loggers Lane Extension: construction of new channels

and habitat, connecting into Phase I through a 30 m fish passage culvert across the Mamquam River flood dyke

N

Loggers Lane Connector Channel Brennan Channel M a m q u a m R i v e r

0.57 m3/s 0.14 m3/s 0.28 m3/s 0.14 m3/s 0.14 m3/s 0.42 m3/s 0.07 m3/s 0.14 m3/s 0.07 m3/s 0.07 m3/s 0.14 m3/s 0.28 m3/s 0.14 m3/s 0.14 m3/s 0.14 m3/s 0.42 m3/s 0.28 m3/s

Mamquam River Diversion Maximum Diversion Rate = 0.71 m3/s

N

2005 Proposed Flow Paths

Environmental Benefits Environmental Benefits

Through this connection, water can once more flow

into the formerly isolated Mamquam River Flood Plain thereby connecting directly into Loggers Lane Creek and Finch Creek

Through these channel works important anadromous

fisheries stocks such as salmon (pink, coho, chum, chinook), cutthroat trout as well as other fish and wildlife species can once more swim directly from Howe Sound into the Mamquam River

N

Estuary Crossing

N

MBC IWMP Objectives MBC IWMP Objectives

To assess the MBC and its tributaries with the

proposed diversion options

To establish the flow path for storm events To determine the work required to reduce

the risk of flooding

Hydraulic Modelling Hydraulic Modelling

Model Development

MIKE 11 Dynamic Model Updated with recent culvert and channel improvements Extended with Loggers Lane Creek and its tributaries Calibrated with time-tag water levels

Storms and Tides Storms and Tides

10-year 24-hour rainstorm = 127 mm 100-year 24-hour rainstorm = 168 mm Match peak runoff with highest higher high water

elevation

All tide gates operating prior to high runoff and high

tide events

Design Rainstorm

• Dry Condition
• 10-year 24-hour
• 100-year 24-hour

Diversion Options

• No Diversion
• Mamquam River
• Squamish Estuary

Land Use Condition

• Existing Condition
• Future Condition

Tidal Range

• Design Tide
• Largest Tide
• Smallest Tide
• Typical Large Tide + Storm Surge

Culvert/Channel Improvements

• Along Mamquam Blind Channel
• Along Loggers Lane Creek
• Along Finch Creek

Mamquam Blind Channel Integrated Watershed Management Plan Simulation Matrix

Results Results – – Scenario 1 Scenario 1

2001 Condition prior to channel/culvert improvements

along Wilson Slough

100-year rainstorm with future land use condition Typical large tide plus storm surge

0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0 800.0 900.0 1000.0 1100.0 1200.0 [m eter]

• 2.0
• 1.5
• 1.0
• 0.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 [m eter]

7-1-2001 00:00

M AIN 0 - 818 10 121 260 390 505 526 555 735 742 754 768 803 818 M AIN 818 - 1179 823 856 1016 1099 1179 M AIN 1201 1220 1230

Loggers Lane Culverts Buckley Culvert Gravel Lane Culvert Hwy 99 Culvert

Results Results – – Scenario 2 Scenario 2

2005 existing condition after channel/culvert

improvements along Wilson Slough

100-year rainstorm with future land use condition Typical large tide plus storm surge

0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0 800.0 900.0 1000.0 1100.0 1200.0 [m eter]

• 2.0
• 1.5
• 1.0
• 0.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 [m eter]

7-1-2001 00:00

M AIN 0 - 818 10 121 260 390 475 505 522 523 553 553 555 735 742 754 768 803 818 M AIN 818 - 1179 823 856 891 1016 1099 1179 M AIN 1199 1200 1220 1230

Loggers Lane Culverts Buckley Culvert Gravel Lane Culvert Hwy 99 Culvert

Wilson Slough

LOB ROB Max WL Channel Invert

0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 1400.0 1600.0 1800.0 2000.0 2200.0 [meter] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 [meter]

7-1-2001 00:00

LOGGERS MAIN 0 - 1043 430 431 442 443 682 700 861 943 1043 LOGGERS MAIN 1043 - 1618 1043 1054 1055 1065 1066 1075 1091 1115 1143 1180 1201 1231 1295 1340 1368 1415 1483 1569 1618 1618 LOGGERS MAIN 1618 - 2181 1661 1677 1737 1770 1867 1890 1931 2005 2064 2091 2181

Raven Dr. Culvert Robin Dr. Culverts Loggers Lane Culverts Finch Dr. Culvert

Loggers Lane Creek

Channel Invert Max WL ROB LOB

Results Results – – Scenario 3 Scenario 3

2005 existing condition with crossing under railway

connecting Squamish Estuary and Wilson Slough

Dry condition Largest tide condition Squamish Estuary diversion through 1 meter diameter

pipe with length approx. 70 m

Results Results – – Scenario 4 Scenario 4

2005 existing condition with proposed crossings under

Loggers Lane and Highway 99

Dry condition Design Tide Mamquam River diversion (0.71 m3/s)

0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 1400.0 1600.0 1800.0 2000.0 2200.0 [m eter] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 [m eter]

29-7-2001 18:40

LOGGE R S M AIN 0 - 667 430 431 442 443 667 LOGGE R S M AIN 667 - 1043 682 700 861 943 1043 LOGGE R S M AIN 1043 - 1618 1043 1054 1055 1065 1066 1075 1091 1115 1143 1180 1201 1231 1295 1340 1368 1415 1483 1569 1618 1618 LOGGE R S M AIN 1618 - 2181 1661 1677 1737 1770 1867 1890 1931 2005 2064 2091 2181

Raven Dr. Culvert Robin Dr. Culverts Loggers Lane Culverts Finch Dr. Culvert

Loggers Lane Creek

LOB ROB Channel Invert Max WL

Results Results – – Scenario 5 Scenario 5

2005 existing condition with proposed crossings under

Loggers Lane and Highway 99

Culvert improvements under Highway 99 Culvert improvements along Loggers Lane Creek and

Finch Creek

All available flap gates used at Loggers Lane 100-year rainstorm with typical large tide

plus storm surge

Mamquam River diversion (0.71 m3/s)

Loggers Lane Culverts

0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 1400.0 1600.0 1800.0 2000.0 2200.0 [m eter] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 [m eter]

7-1-2001 00:00

LOGGE RS M AIN 0 - 667 430 431 442 443 667 LOGGE RS M AIN 667 - 1043 682 700 861 943 965 1043 LOGGE RS M AIN 1043 - 1618 1054 1055 1065 1066 1075 1091 1115 1143 1180 1201 1231 1295 1340 1368 1415 1483 1569 1618 1618 LOGGE RS M AIN 1618 - 2181 1661 1677 1737 1770 1867 1890 1931 2005 2064 2091 2181

Raven Dr. Culverts Robin Dr. Culverts Finch Dr. Culverts

Loggers Lane Creek

Loggers Lane Culverts

LOB ROB Channel Invert Max WL

MBC IWMP 2005 Draft Report MBC IWMP 2005 Draft Report

Impacts of the various diversion options from the

Mamquam River on the upper MBC would be minimal (max increase in water level approx. 0.3 m)

Existing flooding potential along the MBC Culvert/Channel improvements along LLC and FC Squamish Estuary crossing would help rewatering Recommendations for mitigation works

(channel/culvert improvements)

Re Re-

• watering Project Updates

watering Project Updates

Works completed up to 2006:

Intake structure/pipe/channel to divert water from

Mamquam River to Loggers Lane Creek

Ball field channel and crossing under Loggers Lane Bio-filtration channel and culvert extension Upper ends of natural watercourses within

conservation lands south of Finch Drive

Tributary of Loggers Lane Creek along east of

Highway 99 upstream and downstream of Finch Drive

Mamquam River Diversion Mamquam River Diversion

Crossing at Centennial

Way to divert water from the Mamquam River (Brennan Channel) to the headwaters of Loggers Lane Creek

Constructed by DFO

in 2005

Re Re-

• watering Project Updates

watering Project Updates

Works completed up to 2006 (continued):

Channel/culvert improvements along Lower Finch

Creek to the east side of Loggers Lane

Work Completed Flow Path

Mamquam River Diversion

N

Works Completed in 2006

Channel Improvement Ball Field Channel and Crossings Bio-Filtration Pond New Rearing Ponds Lower Finch Creek

Recent Rainstorms Recent Rainstorms

Daily Rainfall Total at Squamish Municipal Hall

November 6, 2006 Event = 108 mm over 24-hours November 15, 2006 Event = 146 mm over 24-hours

10-year 24-hour Rainstorm = 127 mm 100-year 24-hour Rainstorm = 168 mm

1.0 10.0 100.0 1 10 100 1000 10000 Duration in Minutes Intensity in mm / hr IDF curves for Squamish Airport (1982 - 1991) were adjusted by 24 hr return period ratios from the SCTP to Squamish Airport. Curves smoothed for reasonableness of the data. These IDF curves are preliminary and should be refined based on the longer records available at the airport (1982 to date). IDF curves should also be refined when longer tipping bucket records become available at the Squamish Central Treatment Plant. Return Periods Years

100 50 25 10 5 2

5 min. 2 hrs 1 hr 30 min. 15 min. 10 min. 24 hrs 12 hrs 6 hrs

Tide Level and November 6, 2006 Rainstorm

• 4
• 3
• 2
• 1

1 2 3 4-Nov-06 5-Nov-06 6-Nov-06 7-Nov-06 8-Nov-06 9-Nov-06 Date Tide Level (m GSC) 1 2 3 4 5 6 7 Rainfall (mm per 15 min)

Tide Level and November 15, 2006 Rainstorm

• 4
• 3
• 2
• 1

1 2 3 14-Nov-06 15-Nov-06 16-Nov-06 17-Nov-06 18-Nov-06 19-Nov-06 Date Tide Level (m GSC) 1 2 3 4 5 6 7 Rainfall (mm per 15 min)

November 6, 2006 Rainstorm November 6, 2006 Rainstorm

Other Observations:

Mamquam River intake was closed before rainstorm Ball field channel was diverting a significant amount of

flow from Loggers Lane Creek to the conservation lands through Bio-filtration pond

No overtopping at Raven, Finch and Robin Drive

crossings on Loggers Lane Creek

Flooding near the confluence of Loggers Lane Creek

and Finch Creek within the rural subdivision

November 6, 2006 Rainstorm November 6, 2006 Rainstorm

Other Observations (continued):

There was ponding at a low point along Loggers Lane

half way along Lower Finch Creek

A significant amount of flow was observed along Lower

Finch Creek discharging into the MBC

2007 Proposed Work 2007 Proposed Work

Culvert crossing upgrade across Robin Drive along

Finch Creek within the rural subdivision

Replacement of an existing log bridge crossing along

Lower Finch Creek

Culvert crossing upgrade at the lower most drive way

before Lower Finch creek enters the MBC

Additional Modelling Required Additional Modelling Required

Update model with works completed in 2006 Further model calibration with use of the November

2006 rainstorm event

Investigation of drainage path to Britannia Slough Evaluation of proposed culvert crossings along Lower

Finch Creek

Evaluation of a new habitat channel within the

conservation lands

Modelling to assist in developing a protocol for the

• peration of the Mamquam River intake

Thank You! Thank You!

Questions?