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Demystifying the development dilemma Nitrogen cycling: a year-round sport |
The King County Department of Development and Environmental Services Demystifying the development dilemma The Department of Development and Enviromental Services (DDES) is charged with implementing King County’s development and environmental regulations. These regulations cover all aspects of land use and land development in the unincorporated areas of King County. Regulations concerning shoreline development are of particular interest to lake residents. Usually any type of construction activity within the shoreline setback or within the waterside of the ordinary high water mark will require at least a shoreline exemption. Building or Replacing Docks
Building Bulkheads Establishing a bulkhead or adding riprap to a shoreline area is normally permitted only when necessary to protect existing legally established structures and public improvements or to preserve important agricultural lands as determined by DDES. Bulkheading is not usually permitted on the water side of the ordinary high water mark. Establishing Setbacks A setback is the distance required from the closest part of a structure to the ordinary high water mark. Building setbacks vary with the type of environment as defined by the shoreline management act. For urban or rural environments, the setback is 20 feet. For conservancy environments, the setback is 50 feet and for natural environments, the setback is 100 feet. Be aware, setback greater than those established under the shoreline management act may be required under the sensitive areas provisions of the King County Code (KCC21A.24). Accessory structures, such as cabanas, gazebos, or detached decks may be permitted within the required setback area subject to various limitations. As a property owner, you will need to consult with DDES to identify the specific setback requirements and shoreline development limitations associated with your specific parcel. Removing Vegetation or Adding Sand or Gravel A clearing and grading permit is required when clearing, filling, or excavating vegetation or other material within a sensitive area like a shoreline area, steep slope, wetland, lake, or stream. For more information about shoreline development and associated permits, you can call DDES at (206) 296-6640. Getting More Information DDES also has numerous customer service bulletins to address frequently asked questions. Topics of interest to lake residents include clearing and grading; shoreline erosion control; residential building on or near waterfront; and water problems. Copies of these
bulletins can be obtained by calling Paula Adams at (206) 296-6682 or
printed directly from the world wide web at www.metrokc.gov/ddes/bulletin.htm#alpha.
Native plants were showcased and their merits and planting requirements were discussed. The grand finale of the workshop was the ever popular plant raffle where we sent participants home with a native plant of their choosing. If you were unable to attend the workshop, it is not too late to learn about lake-friendly landscaping. The experts can meet with lake groups or conduct follow up sessions. Also, you can contact a neighbor below about lake-friendly landscaping. If you don’t see your lake represented here and would like assistance, contact Michael Murphy at (206) 296-8008.
Nitrogen is a nutrient. Nutrients are foods, or elements needed for growth and nourishment. Nitrogen is an important component of proteins and nucleic acids, and ranks third after carbon and oxygen in quantity required by organisms (including you) to sustain life. Bacteria pedals the cycle
Nitrogen may also be absorbed directly from the atmosphere by special nitrogen “fixing” bacteria and algae that convert it to ammonia (NH4). Ammonia is converted by other bacteria to nitrite (NO2&hibar; ) and then nitrate (NO3&hibar; ), the form utilized by plants. Animals eat the plants and excrete ammonia in their waste products. When the plants and animals die, bacteria break down (decompose) the tissue, also producing ammonia. The ammonia is then converted by other bacteria back to nitrite and nitrate, closing the cycle. In fact, bacteria are the major movers of the nitrogen cycle. Cycling in water Special conditions in lakes can affect the nitrogen cycle. Different forms of nitrogen may dominate at different depths within a lake because of oxygen availability, temperature conditions, and algal activity. In water with low oxygen levels, some bacteria actually reverse the nitrogen cycle by converting nitrate to nitrite and then atmospheric nitrogen. Algae may absorb large quantities of nitrogen from the surface waters of a lake. Also, ammonia levels can be higher in lakes associated with wetlands because their tannins and humic acids inhibit the break down of ammonia in the cycle.
Cycling in King County Either nitrogen or phosphorus may “limit” lake productivity, depending on which is in shorter supply. In Pacific Northwest lakes, phosphorus is usually the limiting nutrient, but in general, higher nitrogen concentrations are also associated with more productive lakes. For May 1999, nitrogen concentrations are compared for some King County lakes (Figure 2). Lakes with good water quality and low productivity like Angle, Geneva, Lucerne, Pine, Pipe, Star and Steel tended to have lower nitrogen concentrations than lakes like Allen, Cottage, Dolloff, Fivemile, Leota, Spring, Trout, and Wilderness which have medium to high productivity. Many of the higher productivity lakes are linked to wetlands which may contribute to the higher nitrogen levels. Keeping your balance Too many nitrogen
oxides in the atmosphere can contribute to acid rain, high levels
of ammonia are toxic to aquatic life (especially salmonids) and
high concentrations of nitrate can cause algae and aquatic plant
problems. So how do you help keep the nitrogen cycle balanced?
Pet and livestock wastes have a high nitrogen content, so dispose
of them properly before they leach into surface runoff or ground
water. Check to make sure your septic tank is functioning properly;
wastewater is also very high in nitrogen. Limit your use of fertilizers;
try using compost or mulch instead. Finally, use native plants
to help prevent erosion of topsoil and lake and stream banks.
Even with these vast natural resources, Spring Lake has some challenges ahead. Residents completed a noxious weed survey of the lake in the summer of ’98 and were dismayed at the extent of Eurasian watermilfoil throughout the lake. Earlier surveys had also shown developing areas of purple loosestrife along the shore. Some of those purple loosestrife infested areas are decreasing as cutting and other measures are being adopted. Also, data collection has shown that the lake levels responds very quickly to rainfall events. This reflects the loss of tree cover and lawn installation around the lake. Even with these challenges, many critters choose Spring Lake as their home. Douglas squirrels are still common and exotics, such as English sparrows, still relatively rare. Lake residents often enjoy sightings of eagles, otters and turtles. Since I own a large wooded lot, I decided to participate in the Backyard Wildlife Sanctuary Program. In order to qualify, you need to provide food, water, cover, and nesting places for birds and other wildlife. Native plants are always a welcome addition as well. Rewards include a newsletter with information about planting for wildlife, reports on wildlife sightings and a sign to place in your yard. To receive a packet of resources and a application for your yard, mail a $5.00 check with your name and address to: Department of Fish and Wildlife, attn: Backyard Sanctuary, 16018 Mill Creek Blvd, Mill Creek, WA, 98012. This is a great way for individual homeowners to positively impact their lake! Thanks to
Caren Adams, Spring Lake Monitor, for this article.
To more accurately identify the source of the sewage, tests for the presence of specific bacteria, such as Escherichia coli or Pseudomonas aeruginosa, have been used. Another technique uses the genetic material RNA (ribonucleic acid) from bacteria which provides information on the animal contributing the bacteria. A recent study using RNA identified domestic cats as the major contributor of fecal coliform bacteria in Piper’s Creek in Seattle’s Carkeek Park (1993). Fecal Sweep 1998
To Swim or Not To Swim... There is no standard protocol among local health departments for closure of swimming beaches. But, a measurement over 200 fecal coliform is considered high by most health officials. In June 1998, King County closed Pine Lake’s swimming beach because of high fecal coliform bacteria levels. Samples collected in June had counts of 440, 980, and 110 cfu/100 ml. Pine Lake was reopened in July after bacteria levels dropped to acceptable levels. Waterfowl fecal matter was believed to be the primary source of the high counts based on shoreline survey results and the numerous waterfowl present at the park. King County will continue to routinely sample Five Mile, Pine, and Wilderness lakes. These three are the only lakes within unincorporated King County which have designated swimming beaches. There are plans to repeat the Lake Stewardship Program Fecal Sweep in August 1999. Beaches on Lake
Washington and Lake Sammamish are sampled routinely for fecal
coliform bacteria. Information about which beaches are routinely
monitored for fecal bacteria can be found at our website http://dnr.metrokc.gov/wlr/waterres/swimbeach/. If a beach is closed
due to high bacterial counts, there will be signs marking the
area. Are you worried about weeds spreading to or from your lake? Interested in informing your neighbors or other lake users about the problem with noxious weeds? To address problems
with Eurasian watermilfoil, purple loosestrife, hydrilla, or
weeds in general, the Lake Stewardship program is offering lake
residents assistance with sign placement at local boat launches
or public parks. These signs are a great way to spread the word
about lake protection. Contact Sally Abella at (206) 296-8382 for
more information. |
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For questions
about information on this page, please contact Sally
Abella.
Updated: November 20, 2001 |
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King County | Natural Resources and Parks | Water and Land Resources | News | Services | Comments | Search 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 
On King County lakes, pier and dock construction
requires either a shoreline exemption or substantial development
permit. If the market value of the construction is less than
$10,000, only a shoreline exemption is required when the resulting
construction is 80 feet in length or less, does not exceed 13
feet in depth, and is 600 square feet or less in surface area.
If the proposed construction is greater than $10,000 or does
not meet the above criteria, a shoreline substantial development
permit must be obtained. Generally, a shoreline exemption takes
about 30-40 days for DDES to review while a shoreline substantial
development permit may take up to 120 days for DDES to review.
Thirty-two eager
landscapers attended the “Landscaping the Lake-friendly
Way” workshop, held on May 22nd and learned about the use
of native plants in landscape design. Besides the Lake Stewardship
Team, three additional County experts were on hand to share their
knowledge — 
Through the nitrogen
cycle (Figure 1), nitrogen is bound and unbound to other elements
as it is absorbed, eaten, excreted, and decomposed. The cycle
starts with nitrogen in the atmosphere (N2) where the energy
of lightening mixes it with water molecules which eventually
become rain. Through direct rainfall, surface runoff, and ground
water, nitrogen enters lakes as nitrate (NO3&hibar; ).
Spring Lake is a
67 acre lake located between Renton and Maple Valley, in a cluster
of lakes including Desire, Shady, Shadow and Peterson. Spring
Lake is different than the rest because about a quarter of the
shoreline is wetland. Also, a large portion of the Spring Lake
watershed is in King County Open Space, protecting it from future
development.
Fecal coliform bacteria
is routinely sampled in water as an indicator of a potential
human health risk. Elevated counts of fecal coliform bacteria
always occur when sewage is present in water. However, the presence
of fecal coliform bacteria does not necessarily indicate humans
are the source of the fecal matter. Many other mammals and birds
can also contribute this type of bacteria to water.
In
August 1998, the Lake Stewardship Program sampled 27 small lakes
in one big “sweep” to evaluate fecal coliform concentrations
at public access points. The results of this sampling are shown
in Table 1. In addition to the Stewardship Program monitoring
event, the swimming beach areas of Five Mile, Pine, and Wilderness
lakes were sampled routinely by the King County in 1998. To find
out the results of sampling these three lakes, check out the
following web page: 
Back
to the Lake Steward index page
