Water Management Water Management of Turtle Lake of Turtle Lake

WatershedWatershedSept 29, 2007Sept 29, 2007

by by Don DillDon Dill

PresentationPresentation Outline Outline

Watershed CharacteristicsWatershed Characteristics

SWA –Sask Water SWA –Sask Water Involvement with Water Involvement with Water Levels since 1984Levels since 1984

Roles SWA Plays in Water Roles SWA Plays in Water Management in WatershedManagement in Watershed

QuestionsQuestions

Watershed Watershed characteristicscharacteristics Gross Drainage Area Gross Drainage Area 649 km 649 km 22

Effective Drainage Effective Drainage Area Area 555 km 555 km 22

Area of Turtle Lake Area of Turtle Lake 64 km 64 km 22

Net evaporation Net evaporation About 340 mmAbout 340 mm

Watershed Watershed CharacteristicsCharacteristics

Inflow Volumes (1 dam = 1000mInflow Volumes (1 dam = 1000m3 3 or 220,000 or 220,000 gallons)gallons)

Volumes (damVolumes (dam3)3) Peaks (m Peaks (m33/sec)/sec) 1: 2 18,700 5.61: 2 18,700 5.6 1:5 26,800 9.01:5 26,800 9.0 1:10 33,000 12.01:10 33,000 12.0 1:25 42,000 15.51:25 42,000 15.5 1:50 49,000 20.01:50 49,000 20.0 Annual net evaporation = 21,200 dam Annual net evaporation = 21,200 dam 33

Water Level PeaksWater Level Peaks

Water level peak this year 655.24 m.Water level peak this year 655.24 m.

1:100 peak water level 655.16 m.1:100 peak water level 655.16 m.

used in hydrology used in hydrology

studiesstudies The 1:00 level is being reviewed to The 1:00 level is being reviewed to

determine if changes need to be made.determine if changes need to be made.

Historical Water LevelsHistorical Water Levels

Outlet of Turtle Lake Outlet of Turtle Lake

April 1990

Silt from ditching carried Silt from ditching carried out July 19, 1984out July 19, 1984

Obstruction placed July Obstruction placed July 19, 198419, 1984

Obstruction May 25, 1985Obstruction May 25, 1985

Obstruction in Channel Obstruction in Channel May 28, 1985May 28, 1985

Outlet July 16, 1985Outlet July 16, 1985

Sask Water Timber WeirSask Water Timber Weir

Overflow elevation varied between Overflow elevation varied between 654.62 m. and 654.93 m. between 1970 654.62 m. and 654.93 m. between 1970 and 1984.and 1984.

Set weir at historical average levelSet weir at historical average level Set at 654.78 m.Set at 654.78 m. Supposed to be temporary until Supposed to be temporary until

consultation completed and new consultation completed and new structure designedstructure designed

Temporary Wood Structure Temporary Wood Structure Installed April 25, 1986Installed April 25, 1986

Temporary Wood Strucutre Temporary Wood Strucutre Installed April 25, 1986Installed April 25, 1986

Planning Study Initiated Planning Study Initiated in 1986in 1986

Public Opinion Survey carried out in June Public Opinion Survey carried out in June of 1986of 1986

Public Meetings held in the summer of Public Meetings held in the summer of 1986.1986.

Petitions circulated with hundreds Petitions circulated with hundreds

signing to object to the elevation of the signing to object to the elevation of the timber weir ( too low)timber weir ( too low)

Lots of consultation but no consensusLots of consultation but no consensus

Watershed Authority Watershed Authority Water Management RolesWater Management Roles

Regulate Water UseRegulate Water Use Example water lines into cabins Example water lines into cabins

Regulate Drainage Activity Regulate Drainage Activity Example farm drainage or diversions for Example farm drainage or diversions for flood control.flood control.

Deal with Drainage ComplaintsDeal with Drainage ComplaintsExample – municipalities impounding Example – municipalities impounding

water with road gradeswater with road grades

Watershed Authority Watershed Authority Water Management RolesWater Management Roles

Deal with Water Management InquiriesDeal with Water Management Inquiries Example municipalities seeking advice on Example municipalities seeking advice on

proper placement of culvertproper placement of culvert

Review sub division applications and advise on Review sub division applications and advise on Estimate Peak Water Levels (Vary between 656.65 Estimate Peak Water Levels (Vary between 656.65 and 655.7 m. for various locations around lake )and 655.7 m. for various locations around lake )

Review Forest Management PlansReview Forest Management Plans

Review projects going through the Environmental Review projects going through the Environmental Assessment ProcessAssessment Process

Changing Watershed Changing Watershed from Forest Harvestingfrom Forest Harvesting

White blocks areas White blocks areas

north and east of lake north and east of lake

are harvested are harvested

areas in 1990 areas in 1990

Watershed Authority Watershed Authority Water Management RolesWater Management Roles

Undertake water quality monitoring with Undertake water quality monitoring with Stewardship groupsStewardship groups

Provide advice and assistance to protect Provide advice and assistance to protect riparian areasriparian areas

Take a lead role in preparing Source Take a lead role in preparing Source Water Protection plans for the north Water Protection plans for the north Sask. Watershed including Turtle Lake Sask. Watershed including Turtle Lake

Main Role of SWAMain Role of SWA

We are working on behalf of you to We are working on behalf of you to protect surface and groundwater supplies protect surface and groundwater supplies and quality.and quality.

Your views and comments are essential Your views and comments are essential for successful management of our water for successful management of our water resources resources

QuestionsQuestions