Long Term Water Levels

Plotting the daily lake level data found on King County’s site https://green2.kingcounty.gov/smalllakes/DailyData.aspx for both Spring Lake and neighboring Lake Desire gives a quick picture into how the two lakes manage water differently during the same time period, and under virtually the same conditions.  Specifically, Spring lake has had a steady increase in lake levels while Lake Desire saw a slight decline over the same period.

Researching further, typical highs and seasonal lows can be plotted over 30 years.  The data from 1987-1988 comes from picture and dock studies and is documented in appendix A.   Data from 2005 to 2019 was provided from Caren Adams' lake level logs.  Some of her data is posted online through King County. The other data points were mined from her notebooks by Caren by request.

Not only do lake levels increase over time, but unlike Lake Desire, the lake level swing or travel has increased as well.  An average summer will drop Spring Lake seasonally about 60 cm.  That distance has consistently grown with some years seeing 80-90 cm of swing. This reflects the tug of war between beavers who raise the level, adding to their dams and humans who must drop the level to protect their land and property.  Without ongoing interventions to reset the lake level, the levels would be even higher today.

While flooding property and forests is not ideal, manually dropping the lake is not either.  We need a healthy lake and eco system that functions in harmony with property owners. We want healthy wildlife, healthy trees and healthy landscapes, and healthy docks.  We are tired of seeing our property flooded, damage and ultimately gobbled up by unmanaged wildlife.  We are looking to form a partnership to effectively address this issue long term and create a healthy balanced solution.

Trapping and Lake Levelers/Beaver Deceivers

The lake level history does show that the lake levelers we used were effective at bringing the lake level down. They did require maintenance and eventually met their demise.  Using a more permanent, lower maintenance lake leveler is likely to offer a longer lasting solution though any solution will require ongoing maintenance and may require future additional levelers if new dams are built.

Data Summary Chart for long term lake levels:

Data summarized from picture analysis, King County published data, personal lake level notebooks of Caren Adams.  Precipitation is estimated based on area historical rainfall.

	Typical High	Event Highs	Low	Low adjusted	Summer Precipitation	Winter Precipitation
10/30/1986			10
3/1/1987	40	45			7.56	56.6
10/30/1987
3/1/1988
10/30/1988
3/1/1989
10/30/1989
3/1/1990
10/30/1990
3/1/1991
10/30/1991
3/1/1992
10/30/1992
3/1/1993
10/30/1993
3/1/1994
10/30/1994
3/1/1995
10/30/1995			30	30			Probably lower based on Lake Desire low
3/1/1996	68	73			7.31	56.0	Probably the high despite lake of data when compared with lake desire., Could be higher but was a spike.
10/30/1996							Indeterminate
3/1/1997	75	83			17.69	56.0
10/30/1997			40	40
3/1/1998	60	73			8.08	35.6
10/30/1998			26	26
3/1/1999	68	88			11.02	55.2
10/30/1999			37	37
3/1/2000					4.80		Indeterminate
10/30/2000			23	23
3/1/2001	62	71			0.00	26.2
10/30/2001			20	0			44 on chart, Guestimated based on Lake Desire
3/1/2002	78	85			6.38	48.0
10/30/2002			16	39
3/1/2003	82	87.5			5.52	36.7
10/30/2003			12	12
3/1/2004	85	91			14.09	43.7
10/30/2004			54	54
3/1/2005	92	96.5			12.40	32.2
10/30/2005			55	55
3/1/2006	85	100			9.61	47.0
10/30/2006			44	44
3/1/2007	85	92			6.68	52.0
10/30/2007			41	41
3/1/2008	86	87			7.98	35.9
10/30/2008
3/1/2009					6.02	39.0
10/30/2009
3/1/2010	75	77			4.83	42.6
10/30/2010			17
3/1/2011	75	77			8.68	51.4
10/30/2011
3/1/2012	75	88			8.16	39.4
10/30/2012
3/1/2013	82	89			8.11	46.7
10/30/2013
3/1/2014	95	100			6.87	47.9
10/30/2014			15
3/1/2015	95	101			6.87	40.0
10/30/2015			16
3/1/2016	90	101			3.37	49.6
10/30/2016			35	50
3/1/2017	95	98			4.29	51.3
10/30/2017			40	55
3/1/2018	95	99			6.87	43.2
10/30/2018
3/1/2019