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The
King County Drainage Services Program
For answers to questions about stormwater, drainage requirements, flooding and water quality, just call (206) 296-1900. If the Drainage Services staff is unable to answer your question, you will be referred to someone who can assist you further. Complaint Investigation When a surface water flooding or water quality problem arises, the complaint investigation staff will investigate the cause and determine whether there is a program available to address the problem. When needed, Drainage Services technicians will visit the site, meet with residents, and investigate the problem. When the investigation reveals that a more detailed analysis is required, the problem may be referred to Drainage Services engineers for review. If the problem is related to a drainage facility maintained by Drainage Services, a work authorization correction order will be referred to the appropriate maintenance staff. In cases where there is a code violation, the problem will be referred to the appropriate enforcement group. Facility Maintenance Drainage Services staff are responsible for checking flow contol and drainage facilities to ensure that standards are met and proper function is occurring. These facilities are typically ponds and underground tanks (which store and treat stormwater) or off-road ditch and culvert systems. Technicians periodically visit these facilities and assess maintenance needs. When maintenance or repairs are needed, the work is authorized by Drainage Services staff. In addition, some older facilities are retrofitted to improve performance or address identified problems. The Neighborhood Drainage Assistance Program
Through the program, trouble spots are investigated and impacts are assessed. Solutions to problems are determined and costs are estimated. Then, all problems are ranked according to their severity and cost to resolve. Funding is allocated to the highest ranking projects. Over the last six years, numerous small capital projects have been constructed under the NDAP and dozens of “quick-fix” projects have been completed. Water Quality Compliance Drainage Services water quality engineers are available to investigate surface water quality problems. These problems may include accidental spills, unusual concentrations of natural materials, absence of Best Management Practices (BMPs) at commercial properties, and non-point source pollution. Water quality engineers make site visits, collect samples and investigate pollutant sources. The engineers provide advice for solving problems, make referrals to appropriate agencies, and pursue enforcement actions. Other Drainage Services Section Programs The Engineering Studies and Standards group at Drainage Services provides specialized technical services, including training and technical assistance for users of the King County Surface Water Design Manual. The manual sets the standards for stormwater controls that are applied to all new development in the county which exceeds minimum size thresholds. Engineers in this group also provide technical assistance to the Department of Development and Environmental Services and other County agencies. For more information
about the drainage services available to you, call (206) 296-1900
or visit King County's website at dnr.metrokc.gov/wlr/dss. In August, the Lake Stewardship staff collected water samples for our second annual Fecal Sweep. The lab results are back and summer water quality was good. Most of the King
County lakes sampled had fecal coliform counts below 200 cfu/100
ml, the standard used by most park managers to assess public
safety. Angle, Killarney, Star and Trout lakes had much lower
counts in August 1999 than August 1998. Echo Lake was the only
lake which had high counts in both years sampled. At Echo Lake,
substantial waterfowl use was evident at the beach during the
sampling for 1998 and 1999. Therefore, waterfowl are suspected
as the source of high fecal counts at the lake. For more information
regarding the fecal coliform sampling event or to get specific
counts for your lake, contact Debra Bouchard.
This summer, the toxic algal bloom at Green Lake was reported in the news and resulted in many calls from concerned residents wondering whether something similar could happen at their lake. The bloom at Green Lake primarily consisted of the cyanobacteria called Anabaena. Cyanobacteria Defined Cyanobacteria, formerly known as blue-green algae, are closely related to bacteria. These organisms are similar in size to algae, and like algae, photosynthesize light, converting it to cellular energy and food. Additionally, cyanobacteria have a special pigment which gives them their characteristic blue-green coloration. Blooming Algae Algal blooms occur when favorable temperature, light, and nutrient conditions allow rapid population growth in a short period of time. Most blooms die back within a week or two, but overlapping blooms of different species may appear as one “continuous” bloom. Favorable conditions for blue-green algal blooms include water temperatures between 72-80ºF, long hours of sunlight, and excess phosphorus and nitrogen in the water. These conditions typically occur in nutrient-rich lakes during the late summer or fall. Local Lakes Bloom Volunteer lake monitors collected water samples biweekly on 40 King County lakes from May through October. These samples are analyzed for nutrients, chlorophyll a (chl a), and algae. The chl a and algae data are used to assess bloom conditions.
Click here to see Figure 1 in greater detail Testing for Toxicity Anabaena, Aphanizomenon, or Microcystis (fondly referred to as “Annie,” “Fanny,” and “Mike”) are the most common blue-greens. These species can produce liver or neurological toxins that affect animals. These toxins can remain in the water a few days to a week after a bloom disappears. Testing for toxicity typically involves injecting crushed algal cells into a mouse and observing the mouse for signs of poisoning. Signs of liver toxins include jaundice, shock, abdominal pain, severe thirst, and sometimes death while signs of neurological toxins include staggering, paralysis, and involuntary muscle movement. Both types of toxins have been known to kill fish, waterfowl, or animals. No confirmed human deaths from contact with a toxic bloom have been reported, but skin irritation and gastroenteritis have occurred in connection with toxic bloom conditions. The mere presence of a cyanobacteria does not mean toxic conditions are present: a toxicity test must be completed to make this determination. Because of the expense, toxicity testing is usually limited to lakes were other signs of toxicity have been observed. Presently, scientists are working to better understand the environmental conditions that cause the algae to produce toxins. Spotting Blooms Blue-green algae
blooms can look like green, blue-green, or brown-green paint
spilled across the surface of the water. Often they can be blown
by the wind and will accumulate along a leeward shoreline. If
you suspect a blue-green bloom is toxic, stay out of the water,
keep animals and livestock from drinking the water, and contact
the Lake Stewardship Program Staff at (206) 296-6519.
The land surrounding the lake was logged in the early 1900s and all the remaining timber is second growth. In years past, river otters were seen in the lake, and coho, sockeye, and kokanee (a landlocked relative of the sockeye) spawned in Pine Lake Creek. In the 1960s, native fish were killed to allow annual stocking with rainbow and German brown trout, even though the warm summer lake temperatures are not ideal for these fish. Today, fishermen frequently catch small-mouth bass. Motorboats are allowed on the lake. However, the 12-mph speed limit precludes water skiing. In 1998, a brief closure of the park occurred in the summer because of high fecal coliform counts. The 1998 closure precipitated a sharp drop in both fishing and swimming, even though the Canadian geese population has been halved (in the past two years) and the coliform problem has not recurred. Over the years, the timing of algal blooms has been erratic. Some years blooms occurred in the spring and then, after some inflow was diverted, blooms began occurring in the winter months. Spring algal blooms and a high phosphoros content in the water prompted the construction of a wetland diversion pipe in the fall of 1988. With the pipe, high phosphoros wetland inflow was diverted directly to the lake outflow. As a result of the diversion, the water level was a foot lower in 1989 than it had normally been and algal blooms ernment staff and installed a weir at the outlet stream. Lake levels rose and algal blooms were reduced. Since 1976, the sedimentation rate in the lake has more than doubled because of intense development in the watershed, and non-wetland phosphoros inputs have increased by 2/3 in the past 10 years. A cove on the southeast arm of the lake has decreased in depth from a reported 10 feet only a few years ago to less than 3 feet now. This filling has been exacerbated by a 1988 shopping center development whose runoff enters the lake. Waterweed surveys in 1994, 1998, and 1999 indicated that Reed Canary grass and Purple Loosestrife are gradually spreading around the perimeter of the lake. In August 1998, an association named Friends of Pine Lake was formed for purposes of education and lake protection. Close to 150 residents have become association members. Because residents of the Sammamish Plateau voted in November 1998 to incorporate and become the City of Sammamish, King County will be turning over its responsibility for the park to the new city. Changes, both political and physical, are occurring rapidly. Residents who love this lake need to ensure that the changes do not destroy the beauty that attracted them to this place. Thanks to
Kate Bradley and Ilene Stahl for this article.
As the lengthy “wet weather” season nears, it becomes timely for a discussion of the chemical make-up of stormwater running towards your lake. As rain falls through the sky, it collects dust particles from the atmosphere and pollutants from the multitude of surfaces leading to your stream, river, or lake. Pollution Defined What is a pollutant? A pollutant is any substance that can render water harmful to people, fish, or wildlife or impair recreation or other beneficial uses of water. The broad range of pollutants includes: metals, sediments, nutrients, toxic organic compounds, bacteria, and the focus of this article—oil and grease. Sources of Oil and Grease Oils and greases are common components of stormwater runoff. They can be petroleum-based or food-related (such as cooking oils). Motor vehicles are responsible for substantial amounts of the petroleum-based oils and greases. People often think that oil and grease find their way into stormwater runoff only when people dump oil waste directly down a storm drain. While storm drain dumping is a serious problem, the petroleum found in stormwater largely originates from road surfaces (Table 1). The greater the street traffic, the higher the hydrocarbon concentrations in stormwater.
A study conducted in Rhode Island found that the oil and grease found in stormwater was primarily comprised of used crankcase oil. This oil can be deposited onto the road (creating the black line down the middle of the road) or dripped by parked cars unbeknownst to vehicle owners. When rain flows over a road or parking lot, oil and grease are washed into the storm drains or ditches, eventually finding its way to a stream or lake. Problems with Oil and Grease Oils and grease
are known to be toxic to aquatic organisms at relatively low
concentrations; they can coat fish gills, prevent oxygen from
entering the water, and clog drainage facilities. Small amounts
of oil or grease can have a large pollution effect. A single
gallon of motor oil from an oil change can contaminate a million
gallons of fresh water. A single gallon of oil dumped into a
stream or river can produce an eight-acre oil slick. |
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For questions about information on this page, please contact Sally Abella at (206) 296-8382.
Updated: November 14, 2001 |
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By visiting this and other King County web pages, you expressly agree to be bound by terms and conditions of the site. The details. |
Lake Steward 
Need assistance with a drainage problem?
Start with King County's Drainage Services Section. This group
can assist lake residents with several of its programs including
Complaint Investigation, Facility Maintenance, Neighborhood Drainage
Assistance Program, and Water Quality Compliance.
Drainage problems that affect private property
may be eligible for assistance through the Neighborhood Drainage
Assistance Program (NDAP). Each year funds are available through
this program to fix drainage problems affecting residents in
the Service Area who pay an annual surface water fee to King
County.
Bloom conditions are generally characterized
by chl a concentrations greater than 8.0 µg/L and
by the dominance of blue-greens over other types of algae. As
illustrated in Figure 1, nine lakes exhibited these conditions.
For most blooms, the cyanobacteria, Aphanizomenon, was
dominant.
At 88 acres, Pine Lake is the largest of
the glacier-formed kettle lakes atop the Sammamish Plateau. The
lake is fed mainly by springs and precipitation, with one outlet
stream flowing from the west side of the lake. The outlet cuts
across a meadow and through a wetland, eventually dropping to
Lake Sammamish.
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