Black Diamond NOW

Lake Sawyer Water Quality - Rock Creek & Ravensdale Creek

Over the last several years, I have regularly posted historical and current water quality data sample results for Lake Sawyer.  Thanks to the King County Lake Stewardship program and local lake steward Ken Docktor, we are able to see and track water quality trends for the lake.  King County also prepares an annual Download 2020-Sawyer-2019-Lake-Stewardship-Monitoring-Report (1) that helps us understand what all this data mean.  However good and helpful this data may be, we also need to understand the quality of water that enters the lake from primary sources.  This means Ravensdale Creek (officially called Covington Creek) and Rock Creek.  If there is a growing problem/risk, we need to know where it is coming from so that mitigation measures can be taken to protect the lake - ergo, our recent focus on the John Henry Mine, Oakpointe's Ten Trails Master Planned Development, stormwater treatment from new development along SR169, development around Lake Sawyer, etc.

Like many government programs, the crash of 2007 led to elimination of many of King County's stream monitoring efforts.  Fortunately, at least a few of these programs were restarted in 2014 and we now have some trend sampling data for influent streams Ravensdale Creek and Rock Creek that are the lake's lifeblood.  Here's a map showing current King County stream sample locations:

Based on data developed through studies undertaken in the early 1990's, we know that Ravensdale Creek historically provides over 60% of annual lake influent flows and contributes less than 30% of the lake's annual nutrient loading of phosphorus and nitrogen.  For Rock Creek, it has been just the reverse and is the lake's primary source of "bad actors" entering the lake.  What do recent trends look like? 

Beginning with water temperatures that have been rising some over the last decade, what do each of these streams look like (latest samples taken through June 2020)? 

Interestingly, monthly sample results show little if any change in stream water temperatures, except for seasonal variations.  Both streams tend to fluctuate in the same cycle with the smaller Rock Creek fluctuating in temperatures with higher highs and lower lows throughout the year.  But no clear trend upward over this period, which is good news.

How about levels of dissolved oxygen which are critical to our fisheries and salmon spawning?

Ravensdale Creek appears to be remarkably stable with high dissolved oxygen levels throughout the year with little if any change over this period.  That's good news.  Rock Creek continues a pattern of significant seasonal fluctuations throughout the year.   

How about total phosphorus concentrations?

Clearly, Rock Creek has significantly higher levels of phosphorus than does Ravensdale Creek with neither stream showing an upward trend.  And keep in mind that stormwater runoff from the Ten Trails development does not flow into the Rock Creek/Lake Sawyer sub-watershed and would thus not impact these numbers.

More sample data in future posts.

Lake Sawyer Water Levels

So far, so good.  Current lake water levels are -3.6" below the weir which compares with the average over the last ten years at this time of -5.9".

Any rain we can get this time of year is most helpful.  

If you are interested in keeping current with lake levels and other related Lake Sawyer weather information, be sure to add the Lake Sawyer Weather web site to to your list of favorites.  Maintained by Bob and Janie Edelman at dock 30, you'll find a wealth of useful information, both current and historical.

Lake Sawyer Water Quality - Latest Test Results

King County recently posted Lake Sawyer water quality test results for samples taken in June earlier this year.  Like always, I would caution that we are looking for trends and cannot reach conclusions based on any sample above or below the "norm".  Measuring lake water temperature is a good example where we can clearly see a trend - the lake is clearly getting warmer.

As we would expect, water temperatures in May/June are lower than they are August, but the trend is up over this ten year period, particularly near the surface.  Since warmer water has less oxygen carrying capacity than does colder water, this trend is not positive for lake trout and salmon populations.

 

Sampling is typically taken each year in May and August.  This year, samples were taken later in June.  Secchi measures the depth at which a disk lowered into the water can no long be seen.  The deeper the better - which means the clearer the water.  Over the last ten years, the trend has been positive with somewhat better clarity.  The two samples taken this year in June show reduced clarity.  We'll see what future results have to tell us.

Total phosphorus is an important indicator of long term water quality.  Lower phosphorus levels mean less "fertilizer" available to spur plant growth in the lake, such as algae, and the better lake water quality will be.  Higher phosphorus levels are not good for the lake and can lead to lake eutrophication and the loss of fisheries.  Essentially, as noted by King County, no trends here over the last ten years and we see lots of variability, particularly at deeper depths.  Our concern over mining at the John Henry Mine has largely been driven by concern for higher phosphorus concentrations being discharged into the lake via the Rock Creek watershed.

More about water quality indicators in future posts.

Footnote:  For those concerned about the potential adverse impact of the Ten Trails development on Lake Sawyer water quality, particularly phosphorus discharged to the lake via stormwater runoff, stormwater runoff from current plats under development do not flow into the Rock Creek/Lake Sawyer watershed and thus do not currently impact the lake.    

Lake Sawyer - Are the Fish Biting?

Judging by all the fishermen now on the lake, trolling or casting as the sun rises and sets each day, fishing must be good this year?   As soon as the state lifted COVID-19 related fishing restrictions in early May, it seems we could have used a full time parking and boat launch attendant at times just to direct traffic at the boat launch.  After being cooped up, people apparently just needed to "get out there" - and hopefully catch some fish too.  From those people I talk too as they go by our dock, it's probably a combination of both ok fishing and it being great to get out.  There certainly are fish, including this largemouth bass caught by a happy angler yesterday morning.

You might note that having a cell phone for taking "selfies" is now standard equipment for most fishermen. Nice fish but this young man carefully put it back in the lake for the next fisherman to catch..

For those not familiar with fishing conditions at Lake Sawyer, the lake is open for fishing year-round.  You won't catch many fish in winter months given cold water temperatures, but by spring, you will have quite a few native and stocked fish to test your skills.  Several lakes in the area, like Lake Wilderness, are set up for seasonal fishing only and stocked with significant numbers of rainbow trout each year targeted for a big "opening day" crowd.  Lake Sawyer also is stocked with some rainbow trout (3,024 on May 6 this year, weighing an average of 2.80 fish per pound) and also stocked with a large number of fingerling Kokanee (65,550  fingerlings stocked this year, maturing in 2021 or 2022, at which time hopefully a good number will have "grown up" to be 1+ pounders).  

Of the fish native to the lake, a number of native cutthroat trout and warm water species such as smallmouth bass and largemouth bass are the most sought after by anglers with sizable numbers of yellow perch, black crappie and brown bullheads (aka catfish) also caught.  Perhaps we can leave the catfish to our local osprey families and have them leave us the Kokanee fingerlings.. 

These largemouth bass can grow to become pretty sizable.

It will be fun to see how the Kokanee (landlocked sockeye salmon) fingerlings grow.  I believe this is the second year in recent history that Kokanee fingerlings have been planted in the lake.  These are nice fish for both catching and eating.  When we first moved here in 1981, I trolled around in my canoe and was able to catch several - one of which was over 1 lb.  From lake to BBQ in a matter of minutes.  Happy fishing.

Muskrats at Lake Sawyer?

We have long known that Lake Sawyer and environs are home to both river otters and beavers.  But muskrats?  Apparently so.  Though I have seen them before swimming under and around our dock, I always mistook them for beavers.  But if you look carefully at their tails, which are much more like a rat's tail, long and roundish, then it's a Muskrat.  In other words, a big rat that swims.  On a clear day with bright sun (too much for good photos), I was able to capture a few shiny images while one frolicked around our dock.

Look how long that tail is.  Not the wide flat tail of a beaver, nor the smooth pelt of an otter.  

You'll be happy to know that muskrats are prolific breeders and may raise 20 or more youngsters each year.  They normally stay very close to their home den, maybe 150 feet or so, which is why I'm surprised to see them where we are on the lake.  

Perhaps they have a den somewhere at the north end of the lake.  They are known to burrow into floating docks and make a nice comfy home in the dock's Styrofoam.  Will have to do some exploring of the shoreline and floating docks up here.  Unlike otters, muskrats' diet consists of grasses and plants growing in shallow areas of lakes and streams.  After this guy finished swimming around under our dock, I got one picture that shows it with it's prize bouquet ready for dinner, taking it back to the den.  Which makes me think their den is pretty close to home.  Will have to go exploring and see what I can find.

Other sightings or observations?

Yeah - The Lake is Open for Fishing

This is the time of year when the "pros" return to Lake Sawyer for a summer of outstanding fishing.  Though they don't need a fishing license from the Washington State Department of Fish & Wildlife, the timing of their annual visit typically mirrors the official "opening day" for the rest of us.  And no concerns about social distancing for these pros.  Who am I referring too - osprey of course,  otherwise known as the fish hawks/aka Seahawks. 

These are real pro fishermen and nobody does it better.  While local bald eagles will dip their talons in the lake to snatch a fish near the surface, they would just as soon have a lunch of duck, fish carcass or squirrel fricassee than go diving for live fish.  Osprey diets are 90% + fish and they really know what they are doing, often diving fully submerged in order to latch on with their talons for dinner.  We get to see lots of "fly-byes" this time of year as local osprey patrol the lake.

Eagles will sometimes perch in a tree waiting for an osprey to catch a fish, then dive bomb the osprey as it struggles to fly with a heavy load.  The osprey has little choice but to let go, dropping its dinner while the eagle swoops in behind snatching the fish in mid-air before it hits the water.

Turnabout is fair play, however.  Here is an eagle reacting to being dive bombed by an osprey from above.

Although smaller than an eagle, the wing span of an osprey approaches that of an eagle, making the osprey quite strong when lifting fish from the water.

I took the above photo at Hayden Lake Idaho, showing an osprey flying away with a kokanee salmon it had just captured.  Here's another one with an even bigger fish.

Spawning kokanee, which by the way we once had here at Lake Sawyer, weigh probably on the order of 3 lbs or more - heavier than an osprey for sure.  My biggest kokanee catch at Lake Sawyer weighed less than this and had not turned red yet, but was sure fun at the time, and tasty too.  Alas, no more kokanee at Lake Sawyer these days.

Enjoy the sights and theatre this summer and hopefully you'll get to see some real pro fishing.

 

2019 King County Lake Sawyer Stewardship Monitoring Report

This past week, King County released the 2019 Lake Sawyer Stewardship monitory report.  It's nice to see the report released right on schedule as in past years despite the current state of affairs.  Special thanks go to Lake Sawyer resident Ken Docktor, who is our local volunteer monitor.  Without Ken's hard work and diligence, we would not have the breath and depth of information about the lake that we need.  Stewardship indeed!  Rather than pontificate, a PDF copy of this year's report is attached as Download 2020-Sawyer-2019-Lake-Stewardship-Monitoring-Report.  

Why do we care about Lake Sawyer water quality?  A picture is worth a thousand words.

Protecting this jewel for our entire community, those of us fortunate to live here and for those who follow, is all of our responsibility.

 

Lake Sawyer Log Dump - Then (1936) and Now (2019)

The first aerial photographs of King County were taken in 1936 and remain available to us today through the county's iMap website.  So much fun comparing then and now parts of town with the most recent aerials taken in 2019.  Many of you may recall that in addition to the sawmill at the north end of Lake Sawyer, the sawmill also maintained a log dump on the west side of the lake to support logging operations in this area that spanned the period 1919 to 1934.  Following is one of the photos of the log dump in operation taken by photographer Clark Kinsey in 1928.

Image courtesy University of Washington Libraries, CKK0197, Clark Kinsey photographer, circa 1928

Does that island in the background look familiar?  Following is an iMap aerial photo taken in 1936, just two years following sawmill closure.  The log dump was still quite visible.  

Note the two railroad tracks shown entering the site at the bottom.  Logs were dumped here and then floated up to the mill.  Here's a broader 1936 view.

The lake outlet to Covington Creek can be seen not far above the log dump.  No weir during this period and not much sign of other human activity, except for the Grove Resort located near the bottom of the picture below the two islands.  Following is a photo of the Grove Resort, where you can see the two islands in the background and the boat house as well.

Photo courtesy University of Washington Libraries, Asahel Curtis photographer, n.d.

Here we are again with this same iMap view taken in 2019.

The Lake Sawyer outlet is now clearly shown as are a whole lot residences all around the lake.  Where the log dump was once located, we now have the Lake Sawyer Resort.

 

Lake Sawyer Triathlon

What do you miss most by being housebound?  Socializing with friends and family - certainly.  But for me, I really miss not being able to go to the gym and getting my regular exercise.  It's going to be tough hiking when the mountain trails finally open up if we aren't in shape.  Finally, I found something that's fun, challenging and great exercise - a weekly Lake Sawyer triathlon which includes kayaking 2 1/2 miles down the lake and back, a 4.6 mile run and a 6.0 mile bike ride.  Extend the run to 6.2 miles (10k) and to 10 miles biking and we're on track for some good summer hiking.  I do cheat a little while kayaking.  I can't resist taking some pictures along the way, like these from yesterday morning.

Making exercise fun keeps me motivated.

And having the expectation of extending myself to do all three in one day (kayaking, running and hiking) once a week keeps me motivated for regular running.

What works for you to keep motivated for regular exercise?  

And maybe Patty Swedberg with Raise the Bar, who also lives on Lake Sawyer and is a wonderful promoter of athletic events, can bring us a real triathlon.  

Lake Sawyer in Spring

Unique sunrise, sunset and Mount Rainier views make Lake Sawyer a special place to be.  Following are some recent photos taken while staying at home and being unsocial in my kayak.

This is a great time of year for kayaking both early and late.  Sunrise and sunset occur at decent hours of the day (6:18 am and 7:58 pm respectively), so you can enjoy amazing morning and evening colors and still get your beauty sleep.  The above photo shows Mount Rainier bathed in morning pink during sunrise and every day the views are different.  This was taken Tuesday morning.

The morning before, this was the view.

And then there is sunset - the following image taken on Monday evening.

A couple of nights before, sunset had very different colors and sky..

At sunset, Mount Rainier lighting is entirely different from sunrise.

My biggest challenge at sunset is trying to take both mountain and sunset photos at the same time while balancing it all in the kayak.  Lighting is entirely different looking to the southeast for Mount Rainier compared to the sun setting nearly due west at this time of year.  And then even a light breeze wants to spin you around.  Try taking pictures while paddling the kayak at the same time.  To make it all work, I've ended up using two separate cameras with different lens focal lengths.  I use a 70-300mm lens for mountain shots and my wide angle 16-35mm lens for sunset images.  Auto settings just don't work well in either case, so I use manual settings including manual focus.  The good news - you get better pictures this way but it tests your agility.

All for a good cause too!  In addition to having fun, 100% of all proceeds from photo sales are donated to help support our Black Diamond Community Center.  Note cards of all photos you see are available for $4 or 3 for $10, 8x10 matted prints for $25 each and 13x19 prints for $30.  I deliver locally too, free of charge.  The Community Center really needs our help during these trying times.

Here's sunrise from our dock.

For more information, you can contact me at craig.goodwin99@gmail.com or on Facebook at Black Diamond NOW Photography.

Hiking "Off the Beaten Path"

It's April, temperatures in the 60's, flowers are blooming and the sun is shining.  What else could you want in the northwest?  Unfortunately, we must remain in near isolation of others while the coronavirus still threatens.  All trailheads throughout the state on federal and state lands are closed, making it most difficult for those of us who thrive in the outdoors to take advantage of the weather. By any measure, though, we are most fortunate.  Our family has avoided exposure to date and there is much for us to do living in Black Diamond and on Lake Sawyer that "city dwellers" simply don't have available to them - including extensive "local knowledge" of where we can go hiking while avoiding others.

Yesterday, Judy and I took advantage of the weather and went hiking to one of our favorite locations along the Green River Gorge, with nary a soul to be seen.  And what did we find?  Trillium of course, our favorite early spring wildflower.

Beautiful trails too.

Calming and peaceful while soaking up the rays along the river.

For those familiar with the gorge, this is one of the best summer swimming holes around with crystal clear water.  Lots to explore here.  

Time to head home, fully refreshed and ready for more ruffing it at Lake Sawyer.  We are soooo fortunate.

Horseshoe Lake Flood Reduction Project

As previously posted Surprise - Horseshoe Lake Once Looked Like a Horseshoe , Horseshoe Lake is fed only by groundwater with no lake outlet.  Thus, when groundwater levels are low due to a lack of rainwater, the lake dries up.  When groundwater levels rise due to heavy rains, the lake then often floods - threatening the 14 homes around the lake and area infrastructure.  As a result, dating back to the early 1990's, King County periodically found itself installing portable hydraulic pumps and pumping flood water out of the lake first to Rock Creek/Lake Sawyer and more recently to infiltration basins south toward the Green River.  King County has previously pumped down lake water levels in 1991, 1996, 1997, 2007, 2009, 2011, 2014 and in 2016.  As one can see, flooding is not an anomaly, but a frequent problem.

After numerous studies and the evaluation of alternative dispersal fields, it appears that a long term solution is now in sight.  Ironically, while many people have immediately pointed a finger at Master Plan Developer Oakpointe as the source of the problem (and they are obviously not), they do have an area on their property that appears to offer a viable solution and one that keeps water pumped from Horseshoe Lake totally outside the Lake Sawyer watershed - a real win-win.  The following map shows Horseshoe Lake, where permanent pumps will be installed, and the planned water line leading to planned infiltration ponds for Oakpointe's Reserve at Woodlands development.

According to King County, the project SEPA process was to be completed in 2019 with completion of Environmental Review and Permitting in May 2020 and construction beginning in 2021.  Under current conditions, there is no telling when this project may move forward, but I'm sure it would be a relief to residents at Horseshoe Lake to have these problems finally behind them, and for King County too.  For more information, follow this King County link to Horseshoe Lake Flood Reduction project.

More Lake Sawyer Mysteries - The End

One last post regarding the mysteries of Lake Sawyer water levels - I promise.  We all know that Lake Sawyer water levels fluctuate significantly throughout the year, rising in wet winter months and falling during dry summer months.  But why does it fall so much?  Granted, both Ravensdale Creek and Rock Creek no longer provide significant inflow during summer and early fall.  However, we do have a weir to help keep from draining the lake during this time of year.  We do get some rainfall in the lake even though the creeks may stop flowing, but it's not sufficient to maintain lake levels.  Where then does the water go?

Following is a closer look at how much rain we get during the months May through September compared to the rest of the year..  

Between 5 and 10 inches of rain over 5 months isn't much and often we find no flow coming into the lake from Rock Creek and smaller flows coming from Ravensdale Creek before they too stop all together for a period.  Thus, we are bound to see lake levels decrease.

During this period of the year, there are several ways in which we lose water in the lake:

Evaporation

Previous studies from DOE in the early 1990's quantified the amount of evaporation we lose throughout the year.  It's a lot more than I would have thought and more of a factor during the dry season.

The above data is based on climate conditions in 1990.  And since water evaporates faster when temperatures are higher and when it's drier and windier, we might expect evaporation rates today to be even higher than when this data was calculated.

Groundwater Loss

Past studies have identified areas, called meltwater channels or recessional outwash soils, through which water flows from the lake into groundwater.  They are thought to be located in the northeast corner and southwest corners of the lake and are not thought to interact with Covington Water District wells located to the northwest of the lake.  As you will see, these flows play a very significant role in declining lake levels during summer months.

Heavy rainfall in November and December are  typically large enough in the watershed to refill the lake and export even more flow to groundwater.  Here's another chart from the consultant study.

Yard Irrigation

What about water that's pumped from the lake by residents for irrigating yards?  There's no precise way to measure this that I am aware of, but I made some assumptions just to get a sense of the potential.

I would think these assumptions to be on the high end but it's not a small amount of water.  In the consultant studies, any irrigation volumes at that time would have been included in the groundwater numbers shown above.

Summary

Unfortunately, to prepare a complete water balance, we would also need to have available measures of how much water from Ravensdale Creek and Rock Creek are still flow into the lake during this period.  Certainly, not enough to prevent lake levels from receding during late summer as groundwater outflows increase.

To read earlier posts regarding this subject, follow these links to The Mysteries of Lake Sawyer Hydrology and More Lake Sawyer Mysteries.

Juvenile Bald Eagles

It's going to be a great week with lots of sunshine.  A perfect time to go birding in the Samish Flats along Bayview Edison Road near the town of Edison in Skagit County.  Salmon runs up the Nooksack and Skagit rivers have ended and a large number of eagles head west to feed on migrating birds that congregate here.  I saw over 30 eagles perched in one tree.  What caught my attention was the large number of immature juveniles under 4 years of age.  At least two thirds were juveniles.  How can you tell a juvenile from mature bald eagles?  Pretty easy.  Following is a picture of a youngster learning to fly here at Lake Sawyer.  

Despite being just 3 or 4 months old, Junior (my nickname for him/her) had grown to be pretty large by then - nearly the size of an adult.  Junior was learning to fly by hopping between branches where they were nesting.  Note the black beak.  That's a sure sign of a first year bald eagle.

Here's another 1st year juvenile feeding on fish in our front yard.  They grow to full size quickly.  Note their feathers - more white feathers on their back and definitely not very graceful.

In the second year, juveniles acquire more white mottling on their back and underwings and their bill begins to turn yellow-brown.

As you can see, they aren't afraid to take on the adults.

In year three, almost there.

And finally, in year 4, ready for a post card.

 

 

More Lake Sawyer Mysteries

Why do lake levels seem to be getting lower each summer and higher in the winter?  The following graphic, updated daily at Lake Sawyer Weather, shows how big the fluctuations have been in recent years.

As discussed in my recent post The Mysteries of Lake Sawyer Hydrology, there appear to be no easy answers to our many questions.  We know that water enters the lake from three main sources, direct precipitation and stream flow from both Ravensdale Creek and Rock Creek, and exits the lake over the weir into Covington Creek, through lake evaporation and groundwater outflows.  But where do we start to better understand these flows?  The most obvious starting point is with precipitation and thanks to the weather station at Lake Sawyer Weather, we have great local data.

Seasonal data can be even more revealing.

What begins to complicate matters, however, is to remember that the Lake Sawyer watershed, which feeds Ravensdale Creek and Rock Creek, is a very large area - totaling over 8,120 acres.  Thus, we also need to understand what is happening throughout the entire watershed.

That's why being concerned about the John Henry Mine and its impact on the Rock Creek sub-watershed is important.  And that's also why we are concerned about stormwater from development within these watersheds.

Given all of this information at our disposal, we should then be able to understand, for example, why water levels in Lake Sawyer reached such a low point of nearly - 40" below the weir in 2015.  Right?  Well, not so easy.

First, we need to recognize that 2015 is not the lowest point we have on record.  That dates back to 1994 when water levels below the weir fell to -40.41".

So what caused 2015 water levels to fall so far and then to rise so dramatically above the weir in such a short time?  As it turns out, it was simple in this case - beaver dams.  Water levels in Ravensdale Creek had backed up and risen so high that WSDOT became concerned about the safety of the SR 169 bridge where it crosses the creek that crews were brought in to remove some of the dams, causing a gush of water to run into the lake raising water levels in a very short period to over 15" above the weir. 

Rock Creek faced similar problems, though not as dramatic.  A local group of volunteers called the Rock Creek Restoration Team obtained a hydraulic permit from State DOE and removed the Rock Creek beaver dams during the summer of 2016.  Thank you all!

Beaver dams are likely to be a recurring problem that we should monitor.  All you have to do is take a walk along the trails of Ravensdale Creek and you will still see lots of them.  

In addition to beavers, the timing of rainfall appears to be a very large factor in how low water levels become.  For example, 2017 rainfall totaled 51.64", the highest annual level we saw in the last 10 years, yet lake water levels still reached a low point of -23.16".  However, little of this rain fell in drier summer and early fall months.  When it did begin to rain in October, the lake filled quickly, rising from -23.16" on October 12 to +0.79" on November 15.  This last year in 2019, rainfall totaled just 35.1" for the year, yet the lake level fell to a low of just -20.7".  That's because more rain fell in summer/early fall months in 2019 than it did in 2017.

This still doesn't answer the question of whether Covington Water District or Kent Water District wells, or lakeside irrigation pumps are draining the lake and by how much, but enough for today.  I'll address these questions in a subsequent post.

P.S.  Thanks again to Bob Edelman for all your work in maintaining the Lake Sawyer Weather website and weather station.  It's invaluable.

The Mysteries of Lake Sawyer Hydrology

Have you ever wondered why Lake Sawyer and other area lake levels fluctuate up and down the way they do?  Is there something nefarious going on?  Are the Covington and/or Kent Water Districts pumping water from our lake? Unfortunately, when dealing with lake hydrology, there are no simple answers.  For perspective, let's take a quick look at Horseshoe Lake, Lake Wilderness and Lake Sawyer.  

Simplest is Horseshoe Lake.  It has no inlet, no outlet and aside from a little rain, it's water levels are essentially 100% dependent on groundwater.  The underlying soil is highly permeable and as groundwater levels rise, so too do lake levels and when groundwater levels fall, the lake dries up.  Flooding here is a long time problem with water at one time even pumped into Rock Creek and then into Lake Sawyer to relieve the flooding.  Thanks to help from Ten Trails developer Oakpointe, it now appears that a long term solution to flooding at Horseshoe Lake is now in the works.  More about this in a future post.

To the north of us, 69 acre Lake Wilderness is also dependent on groundwater "seeps".  It has no permanent stream flowing into it but being larger, it does receive a greater volume of rainwater and also receives stormwater runoff from the surrounding 318 acre urban watershed.  Unlike Horseshoe Lake, Lake Wilderness does have an outlet in Jenkins Creek.  During times of rising groundwater and rainwater runoff, like we saw this past week, the lake rises with some minor flooding but Jenkins Creek eventually relieves the pressure.  In dry weather with declining groundwater levels, lake levels fall accordingly.

At Lake Sawyer, with 279 acres of surface area and a watershed of 8,120 acres feeding two significant streams (Ravensdale Creek and Rock Creek), surface water flows supply the vast majority of lake water.  Another significant stream, Covington Creek, serves as the lake outlet.  As a result, understanding Lake Sawyer hydrology is a lot more complex.  The most complete studies of lake hydrology that I've found date back to 1989, 1990 and 1991.  This was the time when the Black Diamond sewage treatment plant discharged into Lake Sawyer and amid algae blooms and deteriorating water quality, finding an alternative was essential.  Based on these studies, a Water Balance for Lake Sawyer was estimated to be as follows:

Seasonally, the lake's water balance varies significantly as one would expect.  The following chart shows what the study consultants described as the Typical Year given Typical Weather.

But, as we know, weather patterns change and significant variability can occur from year to year.   

Weir water level graphic shown above is courtesy of Bob Edelman and Jack Sperry.  It's no surprise that lake water levels tend to be higher in wet winter months and lower in dry late summer and early fall.  But why the increasing variability?  What's causing it?  Has something fundamentally changed, such as more water being withdrawn from the lake by wells?  Or are we getting less rain now than before? Or what?

I'll explore these questions in future posts.

It's Been Raining!

Not exactly a blockbuster headline, but there certainly has been a lot of rain over the past several days.  Fortunately, we have not faced the flooding that other communities in our area have seen.  I took a drive around town earlier today and found very heavy stormwater flows but no flooding, except perhaps at the bridge along Abrams Ave.   The most visible sign of heavy rains are the high water levels in Lake Sawyer.  According to Lake Sawyer Weather, the local website maintained by Bob Edelman, lake levels peaked earlier this morning at 15.9" above the weir.  Definitely covering our dock.

You might want to find an alternative location for watching water flowing out of Lake Sawyer and into Covington Creek.

Where's the weir?

What weir?  Although water levels are high, we did have higher water levels in the lake as recently as 2016.

Graphics courtesy of LakeSawyerWeather.com

Today's weather forecast shows some easing off of the heavy rains and maybe even some sunshine by Sunday.  Let's hope.

 

Coho Salmon Run Update - No Luck Yet

This past week, I went for a hike along Ravensdale Creek that took me from Lake Sawyer to Ravensdale Lake and back.  Good exercise but no luck in spotting any Coho salmon making their way upstream just yet.  Here's a photo of what we're looking for taken a few years ago.

Let us know if you spot any.  So much fun to watch them spawn.

Lake Sawyer - Sunrise Winter Capital of the Pacific Northwest

Well, I may have gotten a bit carried away with this post's headline, but it's not that far off either.  Living in Black Diamond and at Lake Sawyer, we certainly fly below the radar screen of the photography community in the northwest.  What makes our location so cool is that at this time of year, particularly in December, January and February, the sun rises and sets as far south as it gets.  The angle of the sun is also at it's lowest which results in particularly intense colors.  With Lake Sawyer waters often calm like glass and given spectacular views of both the Cascades and Mount Rainier, we live in a pretty neat area.

Earlier this week, we saw some of this season's most spectacular scenes to date.  Following are photos of my favorite sunrises over the Cascades and of Mt. Rainier so far this year.  This first one was taken on Thurs. 1/30/2020 and the other on Monday 1/27/2020.  For those interested, I've included camera settings used for each photo.  As you will see, I experiment a lot and change settings frequently to best fit changes in lighting and satisfy my penchant for learning through experimentation.

18 mm focal length, f16, 15 sec., ISO 800

Earlier in the week, the clouds parted long enough to give us some great views of Mt. Rainier.  Since the trees have grown tall enough over the years to obscure our view of the mountain, I find it best to head out in my kayak.  This gives me the mobility necessary to find the best locations.

84 mm focal length, f20, 1/100th sec., ISO400

The other advantage of taking photos from a kayak is this keeps you very low in the water and a perspective you don't often see.  I like vertical shots too, though using a longer focal length brings you closer to the mountain.

154 mm focal length, f20, 1/100th sec., ISO 400

Time doesn't stand still either.  The changes in scene and lighting over a short period of time make it challenging to make the appropriate changes in camera settings needed, which I do manually, while also trying to keep my kayak properly oriented.  Without use of a tripod, all pictures are taken with a hand held camera, which results in faster exposures than one might use if on terra firma. 

92 mm focal length, f16, 1/100th sec., ISO800

72mm focal length, f16, 1/100th sec., ISO1000

Back on our dock, more time to play with different camera settings, focal lengths and compositions.

26 mm focal length, f4.0, 4 sec., ISO200

The above photo was the first one I took while experimenting with alternative camera settings and compositions.

16 mm focal length, f22, 3.2 sec., ISO200

35 mm focal length, f22, 30 sec., ISO200

Some fog in these last two photos as the sun began to show on the horizon.  While in my kayak, I use manual focus and a faster shutter speed to keep the image sharp, while on the dock, I can use longer exposures and more auto-focus.

Having too much fun and enjoying the beauty we have at Lake Sawyer - Sunrise Winter Capital of the Pacific Northwest.

Stormwater, Phosphorus and Lake Sawyer

As often stated, protecting Lake Sawyer water quality requires limiting sources of phosphorus discharged into the lake.  Phosphorus is the primary nutrient in lakes that stimulate plant growth, leading to eutrophication - otherwise known as becoming a dead lake.  One way to actually "observe" sources of phosphorus loading is to take a drive around town during heavy rain events.  Fully one third of all phosphorus discharged into Lake Sawyer comes from stormwater during these peak storm events in just a matter of days.

It's been a while since I wandered about in the rain, so I thought I would go out and take a quick look-see, focusing on the Rock Creek watershed where approximately two thirds or more of phosphorus loading into the lake comes from today.  Although I didn't have a turbidity meter with me for taking samples, you can learn a lot simply by observing the clarity and color of the water.  To orient us, following is an aerial photo taken by King County in 2017.  I've added a few labels to help with orientation.

Each of the streams within the Rock Creek watershed are highlighted in blue.  Based on past observations and sampling, I focused first on Ginder Creek as it winds it way down from the John Henry Mine, across SR 169 and on to Rock Creek.  There are two points where stormwater from the mine enters Ginder Creek.  The first is from Ginder Lake.

Even though mining has ceased and reclamation is halted during wet weather conditions in winter months, stormwater continues to flow through two stormwater ponds on site, into Ginder Lake and on into Ginder Creek.   You can see the Morgan Creek residential development to the northwest.  I took a few photos of the creek as it flows through storm drains under the highway.  This is what I saw, labeled on the map as Pic #1.

With no current activity at the mine, there remains a lot of flow and it's quite clowdy.  The cloudier it is (turbidity), typically the higher the phosphorus level.

Then, following the creek south to the intersection with SR 169, another source of stormwater flow from the mine enters via Mud Lake.  First, another map.

Pic's 2 and 3 show significant flows and high turbidity from Mud Lake.  Pic #2

Pic #3

Ginder Creek also has quite a lot of SR 169 stormwater runoff going directly into the stream and full of lots of contaminants.  Pic #4

And finally, two more photos as the creek follows Roberts Drive before going under the road on it's way to hook up with Rock Creek.  Pic #6

Pic #7

And to be clear, no, the above photo is not taken of the city's sewer system.  Fortunately, cleaning up stormwater runoff from SR 169 is included in next year's city Capital Improvement Plan.  In addition, it now appears that Pacific Coast Coal Company is on the path to complete reclamation of the John Henry Mine over the next couple of years.  Once that is completed and then reforested, another significant source of phosphorus currently discharging into Lake Sawyer will be removed.   But, if it's not reclaimed in a timely manner or they once again pursue mining, then we are still in trouble.  Let's hope for the best, but plan for the worst.

Merry Christmas!