State of the Lakes 2012
I’m Richard Litts
Where’s Jason?
Agenda • BRIEF LAKE FACTS • SCIENCE LESSON • NUTRIENT MONITORING • STORM CHASING & SEDIMENTATION • SEPTIC TANK ISSUES • ALGAE /TOXIN MONITORING • WHAT WE CAN DO TO HELP
Watershed South North Tenmile 98 Sq Miles, 10 Tenmile lakes Area (acres) 1129 830 Shoreline (miles) 23.2 19.8 Depth max(ft) 27 27 Depth avg.(ft) 14.8 16.4
Lakes Land Use Tenmile Lakes Watershed Agriculture/range Aviation Industrial forest Land Use Landing strip Mixed federal Mixed ag/range/small wood lot Mixed rural res/small wood lot Federal park Private park Recreational residencial Rural residencial Small wood lot State (forested) State industrial forest State park State prison Unknown forested Urban growth boundary County park N 0 2 4 Miles TLBP Watershed Assessment
Invasive Species
Algae Blooms
Agenda • BRIEF LAKE FACTS • SCIENCE LESSON • NUTRIENT MONITORING • STORM CHASING & SEDIMENTATION • SEPTIC TANK ISSUES • ALGAE /TOXIN MONITORING • WHAT WE CAN DO TO HELP
Start with a Quick Science Lesson…
Three Main Concerns:
Septic System
Phosphorus attaches to dirt
Sediments in Our Lake
Why are we so interested in Nitrogen & Phosphorus? Nitrogen + Phosphorus = “Nutrients” Fertilizer When in high concentrations in our lake, it fertilizes the algae and causes algae blooms.
Agenda • BRIEF LAKE FACTS • SCIENCE LESSON • NUTRIENT MONITORING • STORM CHASING & SEDIMENTATION • SEPTIC TANK ISSUES • ALGAE /TOXIN MONITORING • WHAT WE CAN DO TO HELP
Storm Chasing is a winter water sampling project that allows us to measure the impact that storms have in flushing the watershed and transporting Nitrogen, Phosphorus, and Sediment from the forest and Ag lands of the watershed into the lake.
Storm Sampling Equipment Takes water samples once every 4 hours for 4 days during large storms Sediment = Phosphorus = Fertilizer
Three New Storm Chasing Sites for 2012 Templeton Arm South Lake ~1.4 miles Johnson #3 downstream from J3 Unimproved AG land Johnson #2 Improved AG land Johnson #1 Elliott Forest Boundary
Johnson Creek Sampling Sites
Total Suspended Solids (TSS) (Sediment) Results from Johnson Creek Baseline Non-storm related winter flow (Forest) (Improved Ag) (UN-Improved Ag)
Storm Results from Johnson Creek Storm total rainfall 4.07 inches (Forest) (Improved AG) (Unimproved AG)
Storm Results from All 5 Sites
SEDIMENTATION Remember: Sediment = Phosphorus
Secchi Depth to measure water clarity
Sedimentation Differences Murphy Creek Delta Big Creek Arm (Carlson Arm) Both photos taken March 22, 2012 Secchi depth 1.5ft Secchi depth 11.5ft
Delta Building is also caused by sediments from upstream Murphy Cr Delta Big Cr Delta (Carlson Arm)
Big Cr Arm Sedimentation
Coleman Arm Delta (Benson Cr) 2008 2011 Sediment accumulations of up to 22 inches deep
Johnson Cr Delta Building (Templeton Arm) 2011 Survey marker cap on surface
Run off from forests and Ag land is the primary cause of the winter spikes in N and P.
Eutrophication
Summer Recreation
When You’re fertilizing the lawn, remember… You’re not just fertilizing the lawn
Vacation Home Use
Agenda • BRIEF LAKE FACTS • SCIENCE LESSON • NUTRIENT MONITORING • STORM CHASING & SEDIMENTATION • SEPTIC TANK ISSUES • ALGAE /TOXIN MONITORING • WHAT WE CAN DO TO HELP
Pre-1974 Septic System Survey Worked with county health department to inspect 26 lakefront homes in 2006 and 2007.
Results of Tenmile Lakes Septic Survey Pre-1974 Septic Systems Apparent properly functioning 20% systems. Sites with untreated gray water 33% discharge. 2% System failures with evidence of sewage discharge into lake or 2% ground water. Bottomless tanks identified. 9% Systems in need of repair (not including gray water). Owners with systems in need of repair. 34%
There is no such law that allows “No Septic Grandfathered In ” All properties are required to have properly functioning septic systems. New law next year that requires septic systems to be inspected at the time of a sale or title transfer.
How Bad is it and What are the Consequences? EPA Limit 190 EPA Limit 7.1
Tenmile Nutrient Summary Parameter USEPA Tenmile Lakes (5.5yr avg.) NO 2- +NO 3- 20 (ug/L) 320-510 (ug/L) TN 190 (ug/L) 785-1091 (ug/L) TP 7.1 (ug/L) 36-44 (ug/L) Chlorophyll a 2.3 (ug/L) 7-18 (ug/L)
Agenda • BRIEF LAKE FACTS • SCIENCE LESSON • NUTRIENT MONITORING • STORM CHASING & SEDIMENTATION • SEPTIC TANK ISSUES • ALGAE /TOXIN MONITORING • WHAT WE CAN DO TO HELP
Algae Sampling Program
Algae Bloom Summer 2011 2012
Previous Tenmile Canal Station Carlson 1 Years Station “Z”
Micrographs from Tenmile Lake Asterionella Fragilaria Dinobryon, Staurastrum, & Melosira Anabaena
2011 Health Advisories
Oregon Lakes Issuing Health Advisories in 2011
New Protocols For Determining Lake Advisories • Guidelines will be based on toxin levels instead of cell counts • Better protection of public health because toxin levels are the actual risk factor • Probably result in fewer advisories of shorter duration
Toxin Alert Levels 1ug/L – Drinking water advisory Recreational Advisories
Pet Toxin Guidelines
2011 Potentially Toxic Algae Summary 1ug/L – Drinking water advisory 8ug/L – Recreational advisory
How did 2011 compare to previous years? 1ug/L – Drinking water advisory 8ug/L – Recreational advisory
Current Toxin Report for 2012
New ELISA Toxin Lab Set up in conjunction with the Forest Service and South Slough Lab Faster Results Less Cost
Subscribe to OHA’s email advisories (You’ll be alerted to ALL lake advisories) https://public.govdelivery.com/accounts/ ORDHS/subscriber/new?topic_id=ORDHS_139
Check out our Website for the latest information
Oregon Health Division Drinking water treatment guidance 1. Treatment systems should consist of sand filtration followed by chlorination, followed by activated charcoal filtration. It is essential that sand filtration be done before disinfection to remove as many algal cells as possible without killing or rupturing them. 2. Chlorination systems should be capable of maintaining at least 1 ppm of chlorine residual for at least 20 minutes contact time before the water enters the activated charcoal system. 3. The final step in the process should be effective activated charcoal treatment to remove toxin remaining after the sand filtration and disinfection processes. 4. All treatment equipment used should meet NSF standard 53, and should be adequately sized to treat the maximum amount of water that you use. Treatment equipment needs regular monitoring and servicing to assure that it functions properly. 5. Ideally all water entering your home should be treated as recommended. It is possible to treat only water used in the kitchen, but this increases chances that animals or pets would inadvertently drink untreated water. As more monitoring is done and toxin levels are measured this advisory may be altered. The advisory is to remain in effect until specifically changed or lifted by county and state health officials. Contact Person: Laura Boswell (971) 673-0440
Alterative water sources
Agenda • BRIEF LAKE FACTS • SCIENCE LESSON • NUTRIENT MONITORING • STORM CHASING & SEDIMENTATION • SEPTIC TANK ISSUES • ALGAE /TOXIN MONITORING • WHAT WE CAN DO TO HELP
Watershed Projects • Fencing • Bank Stabilization • Bridges • Riparian Zones • Chlorine Monitoring • Invasive Species Monitoring
Fencing
Bank Stabilization Big Creek Johnson Cr Erosion Mating
Bridges Monson #2 Before and After Monson #1 Before and After
A special Thanks to the STEP volunteers and Riparian Zones private landowners that helped make these projects possible. (Land areas bordering streams or lakes) Plum Gulch Riparian Planting 1999 and 2012
Invasive Species Monitoring
What we hope to never see… Zebra and Quagga mussels or the New Zealand Mud Snail Once these species are established, it is nearly impossible to get rid of them.
Boat Spray-off Station • Construction will start this Fall • Located at the Tenmile Lakes County Park and boat launch in Lakeside • 1 st in Oregon • 2 lanes will accommodate both incoming and out going boat washes at the same time • No charge to the public • Power washer dislodges any attached species • New law will make it illegal to flush boat motors in lake. $129 fine.
Spray-off Station Design E n t e r
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