CLEAR (34N-05E-07) LAKE -- SKAGIT COUNTY: 1995

Size (acres)                         200
Maximum Depth (feet)                  44
Mean Depth (feet)                     23
Lake Volume (acre-feet)             4600
Drainage Area (square miles)        2.40
Altitude (feet)                       30
Shoreline Length (miles)             2.4

Contour Map

Source of morphometric data: Water Supply Bulletins 42, 43, and 57.


VOLUNTEER-COLLECTED SECCHI DATA
________________________________________________________________________________________________________________________
Date      Temperature      Water      %Cloud Recent        Secchi Lake  
(Y/M/D)    (C)   (F)  pH   Color      Cover  Rain   Wind   (ft)   Ht(in) Abbrev. Comments
________________________________________________________________________________________________________________________
        STATION 1
95/05/21                                 0                 21.3     0.0  BASIN LAKE
________________________________________________________________________________________________________________________
   
LABORATORY RESULTS
________________________________________________________________________________________________________________________
                    Total       Total                   Fecal Col. Bacteria  Turb-    Suspended Solids           
                    Phosphorus  Nitrogen   Chlorophyll  (colonies/100 mL)    idity    Total   Non-Volatile   Color  
Date         Strata (ug/L)      (mg/L)     (ug/L)       Site 1    Site 2     (NTU)    (mg/L)  (mg/L)         (Pt-Co)
________________________________________________________________________________________________________________________
        STATION 1
95/05/21       E       7        0.38        1.7          130X      530J       0.5                                
95/05/21       H      16        0.32                                                                             
95/09/06       E       8        0.26        1.8            1U     1400J       0.5U                               
95/09/06       H      11        0.21                                                                             
________________________________________________________________________________________________________________________
E=epilimnion composite, H=hypolimnion composite.  Remarks codes: U = Below detection limits; J = Estimate.


SUMMARY OF VOLUNTEER SURVEY


There was no survey response for 1995.

FIELD OBSERVATIONS OF ECOLOGY STAFF
Eurasian milfoil (Myriophyllum spicatum) is quite abundant throughout the lake.  It
was most noted near the public boat launch.  Fecal samples were collected near-shore
and were most likely contaminated with concentrated waterfowl feces.  

TROPHIC STATUS
Estimated Trophic State:                                 Oligo-mesotrophic
Mean Trophic State Index (Secchi):                       34N* (Oligotrophic)
Mean Trophic State Index (Total Phosphorus):             34 (Oligotrophic)
Mean Trophic State Index (Chlorophyll a):                36 (Oligotrophic)

*The calculated TSI is an estimate.  The Secchi disk hit bottom (B), entered the weeds
(W), or there were too few valid readings (N), or the calculation was based on
qualified data (J), or TSIP was based on spring data (S).

SUMMARY AND EXPLANATION OF TROPHIC STATE ASSESSMENT
Although nutrient/chlorophyll/clarity data collected for this lake may exemplify that
of an oligotrophic lake, the over-abundance of macrophytes within the lake is more
indicative of an eutrophic lake.  The abundance of macrophytes may result in lower
phosphorous concentrations in the water column thus providing misleading information
for assessment.  Based on the information obtained and recorded field observations,
this lake is classified as oligo-mesotrophic.  The near anoxic oxygen concentrations
in the summer hypolimnion is further support for this classification.


COMMENTS FROM 94/08/25 AQUATIC PLANT SURVEY
only checked from shore, collected M. spicatum

AQUATIC PLANT LIST  (This list may be from multiple years and sources.)
Myriophyllum spicatum (Eurasian water-milfoil)  Nymphaea odorata 
(fragrant waterlily)

Data collected and provided by Washington Department of Ecology's Lake Monitoring Program (Maggie Bell-McKinnon, phone 360-407-6124).

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