Black Diamond NOW

Goings On

Two important issues are before our community this coming week:

1. Public Hearing re Black Diamond's city budget for 2019
2. Public Comment period ends re DOE Agreed Order for cleanup of the Reserve Silica mining site near Ravensdale

Black Diamond has scheduled a special Council meeting for Monday December 3rd at 7pm to receive public comment regarding the city's draft 2019 budget.  A copy of the budget can be found at Special Council Meeting Packet.  I know it can be arduous to work your way through all these numbers, but it's important too.  With significant development underway, it's particularly important now.  Increasing our city's financial reserves remains essential.  After having the coffers nearly bare in 2009, steady progress has been made over the years, with the notable exception of the Derdowski council spending of 2017.  The following chart shows beginning and ending general fund reserves. beginning in 2010.

You can find a complete copy of my comments for this year's budget at Download 2019 Budget Comments.  Please let our Council, Mayor and staff know that you care about these issues and support their efforts to continue to shore up city financial reserves.

The Reserve Silica site near Ravensdale and Ravensdale Lake has been closed for surface mining of silica and coal since 2007.  However, dating back to the 1980's, the site was also used as a dump site for hazardous materials that continue to this day to result in groundwater/surface water quality problems at and adjacent to the site.  Mine owners first sought to develop part of the site into residential lots.  Thankfully, with the help of local citizen's, the King County Council's preliminary approvals for changing land use were overturned and owners are now under Order from the State DOE to reclaim and clean up the site.  The public comment period for these reclamation plans can be found at DOE Reserve Silica and Greater Maple Valley Council - Reserve Silica.  This issue is important to Black Diamond and Lake Sawyer residents.  Surface water runoff through current groundwater seeps can contaminate Ravensdale Lake which flows into Ravensdale Creek which flows into Lake Sawyer.

 

Lake Sawyer Water Levels - Current Readings

Thanks to Jack Sperry, we are able to track seasonal water levels in Lake Sawyer dating back to 1996.  As we can all tell just by looking at the lake, water levels have already gotten pretty low - the second lowest reading we have seen for this time of the year since data has been collected on a regular basis.  Here are the trends.

This is how Jack Sperry explained what he sees:

"As you will note on the graphs, the lowest yearly water level in my collection of King County data (1996-2006) and Bob Edelman’s (2010-2018) data using my water level gauge was in 2015(bright green line) when the inlets to the lake were restrained by beaver dams until they were removed.  This year (red line) is showing the 2^nd lowest summer water levels in my data collection.  I believe this is due to unusually lower rainfall this year and early and extended periods of warm and sometimes very hot weather.  We’ve received about 10 cumulative inches of rainfall less this year than at this same time last year and coincidently our water level (red line) is just a little more than 10 inches lower than it was a year ago (brown line)."

Hopefully, the current weather outlook for rain over the next week will help arrest the decline before it gets much lower.

Thank you again Jack for keeping us up to date.

Time for a Visit to the Cedar River Watershed?

Rich in natural resources and rich in history, the 90,638 Cedar River watershed owned by the City of Seattle is a real jewel.  Not only does it provide two thirds of the city's water supply and serve a total population of over 1.2 million people, it is a naturalist's dream - off limits to us all except for a few limited programs and tours held each year.  Many of us have hiked the trail to the top of Rattlesnake Ledge and have seen the beautiful forestlands below and Chester Morse Lake created by the dam in the distance.  Now you have an opportunity for a closer look.  Following is a screenshot of the tours/programs now being offered on the city's website:

I've heard and read so much about the flooding of Moncton once caused by Masonry Dam and the historic mining, railroad and logging towns of Taylor, Cedar Falls, Barneston and Kerriston.  Now we have an opportunity to see and learn from the experts.  Participation is limited and a nominal fee applies.  For example, the Watershed Tour is offered every Saturday and Sunday through September.  Reservations will be needed and capacity is limited to only 30 people each day.  The Family Watershed tour is specifically designed for the shorter attention span of youngsters.  Naturalist adventures also await youngsters.

For those not familiar with the Cedar River watershed, the following map might help.

For more information about these programs and tours, follow this link to Cedar River Watershed Programs and Tours.  I hope that you find the time to take advantage of this fun opportunity.

Water Quality - Lake 12 and Jones Lake

While updating water quality trends for Lake Sawyer, I took a quick look at water quality indicators for two other local lakes.  Lake 12 and Jones Lake will both be adversely impacted by discharge from the John Henry mine should it restart operations.  Both lakes are also currently struggling with water quality challenges.  Following are graphs showing trophic state index trend indicators provided by King County for each lake.  As a reminder, >50 = eutrophic is good for algae, catfish and cloudy water, <40 = oligotrophic is good for salmon, trout and clear/clean water.  Lake 12's numbers are as follows.

Phosphorus concentrations appear to have worsened at Lake 12 in recent years.  In addition, should the John Henry Mine restart operations, this will further increase the amount of runoff and phosphorus going into the lake, potentially adding to current concerns.

Jones Lake appears to have even greater water quality challenges and would be considered as eutrophic today.  The data shown below is the last data available, but there is nothing to indicate that things have gotten any better since then.  To some extent, Jones Lake serves as a "sink" for process water and stormwater generated by the John Henry mine, stormwater from Lawson Hill residences, SR169 road runoff and old town Black Diamond stormwater, before discharging into Rock Creek and eventually into Lake Sawyer.  Without this sink and accumulation of sediment in Jones Lake, it is likely that Lake Sawyer water quality would be worse than it is today.  And keep in mind, what happens to sinks after a while?  They can only hold so much before accumulated sediment begins to overflow and this could significantly and adversely impact  Lake Sawyer.  Here is the data we have for Jones Lake.

More about Jones Lake in a future post.

 

Lake Sawyer Water Quality - Updated Thru May 2018

King County recently reported water quality sampling results for Lake Sawyer updated thru May 2018.  In a nutshell, there was not significant change.  Focusing first on phosphorus concentrations during May, here are my updated graphs.

No data was reported at a sampling depth of 15 meters for 2016 or 2018.  Not sure why.

Secchi disk sampling (a measure of water clarity) also remains in positive territory - five straight years now showing lake water clarity at a depth below the May average going back to the year 2000.   Data collected this year was rounded to the nearest whole number.   

As an overall indicator of lake water quality, King County uses what is called a trophic state index.  A eutrophic lake with an index greater than 50 is what we want to avoid at all cost - they are full of nutrients, weeds and algae.  Great for growing catfish, but not salmon or trout.  An oligotrophic lake with an index of 40 or below is generally clear with high oxygen levels and excellent fish habitat. 

In recent years, Lake Sawyer has remained borderline oligotrophic with good clarity and little if any algae.  Let's not go back to the bad old days of regular algae blooms and cloudy water.  Why are we concerned about process wastewater (coal washing operations) from the John Henry mine and stormwater from the mine being dumped into the Lake Sawyer watershed?  Enough said.

 

Yikes - Feds Give Go Ahead to Coal Mining at the John Henry Mine

Sad to say, the Federal Office of Surface Mining approved plans by Seattle based Pacific Coast Coal Company to reopen the John Henry mine and in the process, ignored our community's concerns about water quality degradation of Lake Sawyer.  Apparently, its ok these days to dump coal mine waste with elevated levels of contaminants into our lake.  In reading through OSM's approval documents, the only thing they apparently took to heart from State, County and citizen input was to require that PCCC begin reclamation if they fail to actually do mining at the site within one year.  In point of fact, this provides no assurance that reclamation will occur.  All PCCC needs to do to continue their blatant avoidance of reclamation is to move some equipment around for a week or so, call it mining, and then do nothing again.  Unless PCCC can "guarantee" that no degradation of Lake Sawyer water quality will occur, the mine needs to be closed for good now and reclaimed.  PCCC should be held to no lower water quality standards than those anti-degradation limits established with the city's Master Planned Developer.

To begin mining, two more permits must be obtained by PCCC - a Water Quality permit from Washington State Department of Ecology and a grading permit from King County.  Needless to say, I encourage us all to be in touch with DOE and do all we can to deny permit issuance.  Algae blooms in Lake Sawyer are too high a price for our community to have to pay.  Following are several links:

Federal Office of Surface Mining - John Henry Mine

Seattle Weekly Article May 25, 2018

Enumclaw Currier Herald May 25, 2018

The John Henry Mine - A Continuing Saga

Along with others I'm sure, I am planning to follow-up with DOE to better understand how we can best make our voices and concerns heard.  I will also follow-up with OSMRE to understand why our input and concerns were ignored.  No explanation has yet been given.

 

Coal Mining in Washington - A Quick Q&A

One cure for excessive verbosity is the simple use of charts and graphs.  Let's give it a try.

How much coal was mined in Washington State during the boom years?

Source: Coal & Coal Mining in Washington, Washington State Division of Mines and Geology, circa 1947

Where was coal once mined in the state and how many people were employed?  

Source: Coal & Coal Mining in Washington, Washington State Division of Mines and Geology, circa 1947

How much coal was mined in Pierce County?

Source: The Mining History of Pierce County, Washington Division of Geology and Earth Sciences, circa 1979

Which Pierce County Mines were the biggest.?

Source: The Coal Fields of Pierce County, Washington Geologic Survey, circa 1914

How big were the mines in our area, including Black Diamond and Franklin?

Source: Bill Kombol, Palmer Coking Coal Company

If employment is any indicator, local mines once accounted for 25% or more of all coal once produced in the state.

Were the mines safe?

Source: Bill Kombol, Palmer Coking Coal Company

During the period from 1887 thru 1927, 203 men lost their lives in local mines.

What about today?  No coal is currently being mined in the State of Washington.  However, Seattle based Pacific Coast Coal Company has submitted an application to restart mining at the John Henry Mine located just north of the City of Black Diamond.  Washington is one of only two states who rely on the U.S. Bureau of Mines for mine regulation and permit issuance.  Despite requests for a status update re Pacific Coast Coal's application, I have received no response from the Bureau of Mines.  

Because operation of this mine poses significant risk for degradation of Lake Sawyer water quality, I submitted my comments and concerns earlier.  But they do not respond.  They used to be quite responsive for info about the mine, but no more.  For more information about the John Henry Mine, follow this link to my earlier post The John Henry Mine - A Continuing Saga.  Once I hear anything, I'll be sure to pass it along.

Local Area Open Space - 1,000's of Acres to Explore

Designating Lake Sawyer as our "Center of the Universe" for the moment, draw a circle with a 15 to 20 mile radius from the center of the lake.  Or use Old Town Black Diamond with the Historical Museum at center and you will obtain the same results.  Within this circle there are nearly 10,000 acres of designated park and open space lands for us all to explore and enjoy.  Most of this land is owned by Washington State Parks, but in recent years King County has acquired large parcels particularly important to us here in Black Diamond.  Other owners include area cities and the Dept. of Fish and Wildlife.  Here's a map with designated open space areas identified.

Dark blue lines represent regional trails.  Green areas shown are owned by King County, bluish green areas owned by the State and the smaller greenish brown areas owned by cities.  Light blue lines represent rivers and streams.  Following is this same view taken from aerial photos maintained by King County using their wonderful tool King County iMap.

King county has aerial images dating back to 1936 with the most current being 2015.  It's very easy to zoom in with high levels of detail and get a historical perspective on development in our area over time.  But first, we have so much open space lands to explore..  I encourage each of us to find open space areas on this map that you have not yet visited and would like to see.  To find ways to access, open iMap by following the link shown above and zoom in and move around until you find the areas you are interested in.  Pretty amazing.  Easy to use after just a little time to play with it.  You can even find out your neighbors' property tax assessed values and property history if you would like.  More about historical mapping and what we can learn in future posts.

Hoarfrost - Frost on Steroids

While walking the trail along Ravensdale Creek this morning, Judy and I were disappointed to not see Coho salmon spawning in the stream.  Perhaps a little early or maybe too late this year.  Will have to keep checking.  Nature, however, never lets us down and there is always something special here.  As a wise sage named Thoreau once said, it's not what you look at that matters, it's what you see.  For us this day it was hoarfrost, something we may have noticed but not seen before.  What a treat.

How unusual.  What is hoarfrost?  It looks more like an old man's beard than ice particles.  On days like today, clear and cold with temperatures well below freezing, water vapor molecules come in contact with subfreezing surfaces such as leaves or branches and transform directly from gas to solid state.  The process is called "deposition", leading to a coating of tiny ice crystals.  

They grow longer and longer one upon another, creating these fascinating crystalline structures.  I love the contrast between hoarfrost and moss.  The hoarfrost looks like an upscale cousin or perhaps a tree's jewelry.  Ideal places for hoarfrost to grow are along streams or in foggy areas with high moisture content and cold winter air.  The longer these weather conditions persist, the longer a beard of hoarfrost can grow.  Once we started looking, pockets of hoarfrost seemed to be all over.

Looks like these crystals were created by a hairdresser.  Isn't it amazing what we can see if we but take notice.
 

 

How Much Are Your Trees Worth?

The answer is a lot according to a new computer model called the National Tree Benefit Calculator.  Obviously, this is not something used by timber cruisers in the logging business.  The model is intended to help quantify the annual value of trees grown in an urban/suburban setting.  We have quite a few large douglas fir trees on our property so I thought I'd see what the model calculates as their value.  Here's the results for an average 45" diameter douglas fir growing in Black Diamond based on our climate data - nearly $118 per year per tree.  

According to the model, reduced stormwater represents the biggest economic value here.

Calculating this value for stormwater is based upon these assumptions:

"Trees act as mini-reservoirs, controlling runoff at the source. Trees reduce runoff by:

• Intercepting and holding rain on leaves, branches and bark
• Increasing infiltration and storage of rainwater through the tree's root system
• Reducing soil erosion by slowing rainfall before it strikes the soil"

Though the benefits they cite are indeed true, the values may be a bit overstated here at Lake Sawyer given the highly permeable soils we have and our rain garden.  But there is no doubt, our 20 douglas firs drink up a lot of water.

Energy savings, principally through providing shade and cooling in the summer are also calculated.

According to the model:  "Your 45 inch Douglas fir will conserve 200 Kilowatt hours of electricity for cooling and reduce consumption of oil or natural gas by 21 therm(s)."  Since we don't have air conditioning, this would not apply to us specifically but in an urban environment it may not be far off the mark.  

Each of our firs is calculated to reduce atmospheric carbon by 441 lbs. per year.  "They sequester ("lock up") CO2 in their roots, trunks, stems and leaves while they grow, and in wood products after they are harvested.  Trees near buildings can reduce heating and air conditioning demands, thereby reducing emissions associated with power production."

Overall, with 20 big trees we stand to benefit by over $2,000 per year and this excludes property value benefits.  Big maples would pencil out at even higher benefit numbers.  Though the financial calculations may be a bit over the top in our circumstance, the model provides a fun reminder that trees benefit us not just aesthetically but environmentally and economically in many other ways as well.  Plant a tree - make your day.

 

 

The John Henry Mine - A Continuing Saga

The John Henry Mine closed surface mining operations in 1999.  In July 2010, the U.S. Office of Surface Mining (OSM) notified mine owner Pacific Coast Coal Company that they must commence mine reclamation immediately, denying a PCC permit application for the restart of mining activities.  To quote from OSM's letter:  “After eleven years with no mining activity or reclamation, the company must be held to a reasonable standard, which is why OSM has denied Pacific Coast’s permit.”   PCC appealed and was issued a permit to restart mining, delaying costly mine reclamation.  What's happened since then?  Nothing.  No mining.  No reclamation.  Faced with expiration of PCC's mining permit, they submitted a new application to extend their permit for another 7 years, expiring in 2024.  

For those not familiar with the site, following are a map and an aerial photo taken in 2015 from King County iMap showing the mining site.  

The very southern part of the mine, only about 25 acres of the 500 acre total, is located within Black Diamond city limits.  The mine site is bordered by the Black Diamond - Ravensdale road to the west, city of Black Diamond and Lawson St. to the south and 270th and Lake 12 to the east.

There are at least three very good reasons to deny issuing a mining permit extension:

1.  As the Nov.10 article in the Seattle Times phrased the issue, it's one of "Small Potatoes or Climate Change Disaster.  

2.  Based on past behavior, it appears to be nothing more than a Reclamation Deferral Scam.

3.  We face significant Lake Sawyer Water Quality Degradation if the mine restarts.

King County Executive Dow Constantine has vowed to fight permit issuance to the end.  Let's hope that he can be successful in winning the argument about "small potatoes" because if he doesn't, our community is going to pay a big price.  Unfortunately, the county's argument appears to provide little focus on the very real and tangible adverse consequences on our community if PCC is issued another operating permit extension.  These for me are the big issues.  Thanks to a heads up from city staff, I was made aware that a public comment period was open thru October 17 and I was able to provide public comment in time - addressing both reclamation and water quality issues as best I could.  Rather than paraphrase my 10 pages of comments, I have attached a copy of these comments for those interested.  This should be a very serious concern to us all.

Download Comments re John Henry Mine

Also attached is a copy of King County's official response to OSM dated Oct. 17.  In my opinion, it is not very strong, particularly when it comes to water quality impacts on Lake Sawyer.  Let's hope that the most recent publicity in the Times awakens staff to take this far more seriously.

Download DPER letter

Will keep you apprised as I learn more.

 

Lake Sawyer Water Quality Trends - Chlorophyll-a

Chlorophyll-a is the third water quality indicator used by King County when calculating an overall water quality index known as the Trophic State Index.  In earlier posts, I focused on Phosphorus and Secchi Disk Clarity and will pull all three together for an overall Trophic State Index once we have August data available.  Chlorophyll-a concentration measures the abundance of phytoplankton.  The higher the chlorophyll-a, the higher the algae growth we typically see.  All algae use it in order to complete the photosynthetic pathway by which they store energy.  Following are 2001 - 2017 sampling results for Lake Sawyer first taken in May of each year.

As we can see, trends over this period are very positive measured at both 1 meter below the surface and 8 meters below the surface.  The lower the Chlorophyll-a during the growing season, particularly near the surface, the less algae growth we should see and that appears to be the case.  We have seen little algae at our area of the lake the last few years.

August measurements, however, are significantly more variable.

Although May data consistently show higher concentrations nearer the surface than down at 8 meters, in August this reverses and measured values at 8 meters significantly exceed that for 1 meter below the surface.  In addition, 2015 and 2016 both showed a significant spike in chlorophyll-a measured at 8 meters compared to the average of prior years.  Not quite sure what to make of this yet.  Water levels in the lake were extraordinarily low in both 2015 and 2016 which could be a factor.  But we'll have to see results from this year's sampling in August to learn more about what might be going on.  2017 data for May certainly doesn't show any anomalies.  And as King County keeps saying - one data point does not a trend make.  We'll see.

The Black River - A River No Longer

Until 1916, the Black River linked Lake Washington with the Duwamish River, and the water was deep enough for steamboats to travel between towns on the lake and Puget Sound. After the lake was lowered in 1916, during construction of the Lake Washington Ship Canal, the Black River dried up and gradually disappeared. This photo shows the Black River as it looked around 1898-1900.

Photo courtesy Museum of History & Industry, 1988.33.286, Anders Wilse photographer, circa 1899

What was once the streambed of the Black River is currently the site of the Renton Wastewater Treatment Plant and its point of discharge.

Lake Sawyer Water Quality Results - Secchi Disk Water Clarity

Every May and August, a team of volunteers for King County conducts testing of lake water clarity.  In simple terms, they lower a "flashy" disk into the water and measure at what depth they can no long see the disk.  Technically, it's called a Secchi disk. The deeper the better, meaning the lake is that much clearer.  A murky lake without much transparency of light at shallow depths would typically be more "eutrophic" with lower dissolved oxygen and algae blooms more common - and less hospitable for fish.  We obviously don't want that.  Walking out on our dock this past weekend, I was surprised and quite pleased to see how clear the water was all the way to the bottom.  It sure looks to be getting clearer from year to year but what does the measured data say?  King County has not yet posted results for this year but they do have results posted thru 2016.  Here are the reported Secchi results for the years 2001 thru 2016.

Once again, the higher the Secchi values, the deeper and clearer the water and the better the water quality.  As we can see, measurements in May are typically lower than in August.  Fresh water flowing into the lake from Ravensdale Creek and Rock Creek in the spring bring with it higher levels of particulate making the water murkier at that time of year.  As the summer progresses, this particulate settles out and/or is carried over the spillway into Covington Creek.  By August, Sept. and Oct, water clarity typically reaches its peak.  It sure looks good right now.

It's important to note that one should not try to read too much into results from just one year to another.  King County makes the point that only until you have an 8 year or so trend, can we draw conclusions about lake water quality improving or worsening.  Thus, I always try to include charts with data spanning 10 or more years - in this case from 2001 thru 2016.  Not only is the 15 year trend very favorable, it appears to have accelerated improvement in water clarity during the past several years.  Let's hope that these trends continue.  Will add 2017 data to these charts once King County releases the data.

Special thanks go to Lake Sawyer resident Ken Doktor for taking the time to be trained by King County and who now spends many an hour each month taking water quality samples, helping us all protect the lake.    It should be noted that Ken is also a member of the Rock Creek Restoration team.  Thank you Ken!!!!

Note:  King county reports no data in their records for the year 2005 and that is why these charts exclude data for the year 2005.

Lake Sawyer Wildlife

I recently had occasion to pull together some photos of Lake Sawyer wildlife for use as potential signage at Lake Sawyer park.  We are so blessed with the variety we have in our watershed calling the lake home for at least for part of the year.  Top of the food chain?  I would nominate the otter family.  Here's a couple of my favorite otter pics in and out of water.

I regularly post photos of our bald eagle family who nests 5 or 6 months of the year in the park.  Here's one I haven't posted for a while showing a young juvenile learning to fly by gliding from branch to branch in the nest tree.  The next day after this picture was taken, the family headed north with two juveniles teaching them all they need to know for survival.  It can take 2 to 4 years for a juvenile to mature into an adult complete with white headgear and we often see them return much to the distress of their parents.

What are your favorite ducks that make Lake Sawyer their temporary home?  My favorites are the Canvasbacks and Wood Ducks - both of these photographed in the outlet area of Rock Creek where it flows into the lake.

Cormorants and Osprey are well suited to the lake and spend much of the year here.

Our responsibility is to maintain and continue to improve water quality of the lake and it's tributaries/watershed.  If there is one thing that we can control in our city of Black Diamond, it's water quality.  Each and every one of us can contribute.  Interested in learning more?  This blog regularly features articles about Water Quality including the most recent posts Rock Creek Restoration Team and Lake Sawyer Water Levels Back to Normal.  Want to become involved?  Just let me know your interest and will do my best to get you involved.

And we can't forget the Coho salmon who spawn each year in Ravensdale Creek.

 

Rock Creek Restoration Team

Thanks to the initiative and lots of hard work by a team of volunteers, Rock Creek has been transformed from an oxygen depleted swamp back into the free flowing stream that it once was, capable of supported salmon and steelhead runs.  They call themselves the Rock Creek Restoration Team. 

Members of the team pictured above include Ron Taylor, Ken Doktor, Jay Newton, Joe Riordan, George Coulbourn and Tom Czaplinski.   Not pictured are Chris Niesner, Christian Ciaparrone, David Hagen, Rich Hawkins, Kevin Broom and Chris Ollom.

Determined to restore Rock Creek and its fishery, the team worked with the Washington State Department of Fish and Wildlife and obtained a Hydraulic Project Approval permit for "removal of debris from beavers (including beaver dams) at culverts and short span bridges."  According to project leader Ron Taylor, "using all manual labor and hand tools, we began to open and clean the waterway".  Over 30 beaver dams that had been blocking the flow of water have been removed and we now see free flowing water between Jones Lake and Lake Sawyer for the first time in years.  According to Ron, "this was more than about beaver dams.  We cleaned deadfalls and trash and parted vegetation to assist in water flow.  Our goal was to begin to think of an area that would once again be a stream through a forest that was a healthy habitat for lots of wildlife, good spawning ground and a recreation area where one might go fishing or paddle a canoe".

Not only has this volunteer driven project reduced flooding behind the dams, it has also had a dramatic impact on Lake Sawyer water levels (see my earlier post Lake Sawyer Water Levels - Back to Normal).

We all owe a big THANKS to the Rock Creek Restoration Team.  Great job!

Lake Sawyer Water Levels - Back to Normal

After two consecutive years of dramatic declines in Lake Sawyer water levels during summer and early fall, current water level measurements put us pretty close back to "normal".  Thanks again to Jack Sperry, following is a chart showing water levels over the last 8 years.  2017 data is shown in red. 

Why such steep declines in 2015 and 2016?  Three factors likely account for declines in lake water levels:

1. Snowpack - The higher the snowpack, the greater the snowmelt lasting into summer.  This means more water flowing longer through Ravensdale creek and Rock creek and less lake water flowing out as groundwater.  2017 has been a good year while 2015 and 2016 were years of low snowpack.
2. Evaporation - During periods when no water flows into the lake from Ravensdale creek or Rock creek, evaporation can account for 10" to 15" of water level decline.  This is close to the Mean Low Water Level of 14.7" shown in the above chart.  For more about lake evaporation, read my earlier post Lake Evaporation - How Much of a Factor.
3. Beaver Dams - During 2015 and 2016, water stopped flowing into Lake Sawyer from Rock Creek as early as April with Ravensdale Creek ceasing to flow a month or so later.  This year, thanks to the hard work done by the Rock Creek Restoration Team, 30 beaver dams were removed along Rock Creek between Jones Lake and Lake Sawyer.  Water flowed freely in this area for the first time in years and water levels and flooding behind the dams also declined appreciably.  No doubt this action, taken by volunteers with permits for their work issued by the State Dept. of Fish & Wildlife, has had a major beneficial impact on lake water levels and lake water quality.  Many thanks to our team of volunteers - more about them is a future post.

For those new to Lake Sawyer or for those who need to be reminded regularly, we have very tight water quality restrictions on the lake and "strictly enforced".  Everyone is watching!

I hope that you are enjoying this summer as much as we are.  Thanks again for the data Jack!

Land of Lakes

How many lakes do we have in our backyard here in Black Diamond?  Draw a 10 mile circle around Lake Sawyer and you'll find a lot.  Following is a list of nearby lakes - a few with parks and several with public boat launches for spring and summer fishing.

Of 31 lakes, 12 have public access with boat launches.  My tip for the least known waiting for you to explore?  Try Walker Lake.  They are all beautiful, particularly at sunset and sunrise.  Following is one of my favorite photos from Nolte State Park/Deep Lake at sunset.

 Happy exploring!

 

Elwha Dam - Then & Now

The early 1900's were boom times for building hydroelectric dams in Washington State.  Locally, we had dams and power plants built at Electron, Lake Tapps/Dieringer, Snoqualmie and the Masonry dam on the Cedar River near North Bend.  The Puget Sound region was growing exponentially and in dire need of electrical generating capacity.  The same can be said for the Olympic Peninsula where Port Angeles was emerging as a hub for both forest products manufacturing and shipping.  To supply power meant building a dam 7 miles upstream on the Elwha River.  Dam construction began in 1910 and opened in 1913.  Construction at the site, however, was done on the cheap.  Initially, it was built unsecured to bedrock and washed out before it could be opened.  Repairs were made but no fish ladders were ever provided, even though they were common practice at the time.  Following is an early photo of the Elwha dam and Lake Aldwell reservoir behind it.

Photo courtesy North Olympic Heritage, ELWHADAMS012, Philip Wischmeyer photographer, n.d.

Lacking passage meant removing 38 miles of upstream salmon spawning habit along with 30 more miles of tributary habitat.  Salmon runs that once numbered about 400,000 fish dropped to less than 4,000.  Fast forward to today.  Port Angeles remains an important shipping and forest products manufacturing hub but the scale of need for electricity is light years advanced.  The two dams built on the Elwha could supply no more than 30% of the power supply required by just one pulp mill.  No longer vital, both dams were removed and the river flowed freely again in 2012.

I had the opportunity to revisit the dam site last week.  Habitat recovery and restoration is proceeding rapidly.  Following is a picture of the river as it now flows through the previous reservoir.

A whole lot of land was once underwater.  Following is a view of the dam passage now breached.

I was here two years ago at about this time and the water was really muddy.  Not today even with all of the rainfall we've had this spring.  Rewarding to see what appears to be a real conservation success story.  Here's the Elwah at night.

If you have the opportunity, it's easily accessible and well worth the trip.

Lake Sawyer Water Quality - Baseline Phosphorus Levels 2011 - 2014

In last week's Lake Sawyer Water Quality post focused on Impacts of Development since 1990, we found that significant development occurred in the Lake Sawyer watershed following completion of King County's water quality studies in 1991.  With added development, it is reasonable to expect that both stream flows and phosphorus loading to the lake would have increased since then given greater volumes of stormwater runoff generated by this new development.  How much, of course, is difficult to estimate.

Though no homes have yet been built, we now face significant new development as a result of Oakpointe's Master Planned Developments in the months ahead.  What impacts on Lake Sawyer water quality can we expect from the MPD's?  If our concern is phosphorus loading to the lake, the MPD's should have no net impact.  A requirement of the Development Agreement (DA) states that there be no net added phosphorus loading to the lake as a result of the MPD's.  Sounds good but how will we know if these conditions are being met?  To meet the conditions of the DA and further enhanced by the Hearing Examiner in his Preliminary Plat 1-A decision, requires, among other things, that a baseline of current monitoring data be established against which phosphorus loading in future years can be compared to ensure compliance with the DA. As a result, baseline monitoring in the Rock Creek sub-watershed occurred in 2011-2014 with a report summarizing study findings published in March 2015.  Interestingly, these studies also provide insight into what impacts development that occurred between 1991 and 2015 have had on Lake Sawyer water quality.

Baseline flows and phosphorus loading concentrations were measured at three locations along Rock Creek - at the Abrams Avenue bridge, at the Robert's Drive bridge and at the culvert in Lake Sawyer Park as flows enter the lake from Frog Lake.  In study documents, Roberts Drive is referred to as the Auburn-Black Diamond road and the Lake Sawyer park culvert is referred to as 312th.

Following is a summary of the results presented in the 2015 published study:

To quote from the study report, "Total annual TP load estimates in this study reflect current background conditions at each of the three Rock Creek sites.  Any differences from previous studies (Carroll and Pelletier, 1991) describing background conditions reflect changes in the drainage and human activity that influence the Rock Creek drainage area."   I would also add that changes in rainfall between 1989-1990 and 2011-2014 also have an impact.  The following compares data from the 1991 and 2015 published studies. For simplicity, I converted total annual flows in the 2015 study from Liters to cubic feet per second.  The 1991 study reported flows and phosphorus loading only at the 312th culvert location and did not differentiate between storm flow and base flow.

    1991 Study                             9.7 cfs  stream avg. flow                304.0 kg/yr Total Phosphorus

    2015 Study                           13.4 cfs  stream avg. flow                406.8 kg/yr Total Phosphorus

    2015 as % of 1991                       138%                                        134%

Given that the number of new homes built within the Rock Creek basin between 1991 to 2015 added on the order of 60% to the drainage area's housing stock, it is not surprising to see a significant increase in phosphorus loading during this period.  It is, however, quite surprising to see Rock Creek flows grow by such a large amount.  With more impervious surfaces, we should expect more surface water runoff - but 38% more???? 

As it turns out, the Puget Sound Region has seen significant increases in rainfall between 1989-1990 and 2012-2014 as the following graph illustrates:

The correlation between rainfall measured at SeaTac and the Landsburg NOAA monitoring station is quite high, with Landsburg consistently higher as we might expect.  Being located at a higher elevation (535' compared to 262') and further east, closer to the Cascade foothills, we should expect higher levels of rainfall at Landsburg (and Lake Sawyer).  Landsburg is located just 4 miles northeast of Lake Sawyer and very near the boundaries of the Lake Sawyer watershed.  Rainfall at both SeaTac and Landsburg are considerably higher during the 2011 - 2014 study period compared to the 1989 - 1990 study period and therefore likely accounts for the largest share of increased flows reported above.

Given that stormwater runoff from the currently approved Preliminary Plats 1-A and 2-C have little if any impact on the Rock Creek drainage (stormwater from these plats flow to a drainage basin south and west of the Rock Creek basin), we should expect to see little if any further monitoring data for Rock Creek for a while or until Oakpointe submits application to develop additional plats that do discharge stormwater into the Rock Creek basin.

This data does, however, point to the need for us to continue pursuing improvements to stormwater collection and treatment for existing sites within the Rock Creek drainage.  #1 on the list - SR -169 highway runoff collection and treatment.  More about this in a future post.