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<br />~~ -' The 2003 nreakdown of overall lake water
<br />2002 and 2003.Of these, lake rades were
<br />g ~ -- qua6tygradesofarealakes"
<br />~- ~~ :; ~ erg Sgs~e~ A,. _~~~+~~
<br />Each lake monitored in 2003 was assigned a water unchanged for 64 /o, increased for 21 /o, and ~a~~E" Qta Y C~radl
<br />deveilo geddb C ing an A though F grading system decreased for 16 /o. Analyses of the t12 repeat takes
<br />p y ouncil staff in 1989. The grading seems to indicate that the areas lake water quality a ~A ~
<br />system uses percentile ranges for three water qual- may have been similar to slightly better in 2D03 as ~I ~ ~ o ~ - - ~ ~°
<br />ity indicators-summertime (May-September) aver- compared to that recorded in 2002 '- ~ u ~~s $ o) za
<br />age values for total phosphorus, chlorophyll-a, and ' z.z ts.: ~ F''~ ` rT III
<br />Secchi depth transparency--developed from the Similar to that of past years, analysis revealed no dis- ~ z.r}.z p.aasl I ___~_ _ : _
<br />9 2-e.T (3.8 2b}
<br />Council's TCMA lake water quality database. Total tinct pattern within the region as to where takes with ~ € ' 52 - >r r yz ~o ~ so co ~o
<br />phosphorus is a key nutrient measure, chlorophyll-a specific water quality are °Assessmentwas completed only fo€ taxes
<br />is a measure of algae abundance, and Secchi located. Nor were with an adequate database
<br />depth transparency Is a measure of water clarity there clear-cut areas ~ ~ -,~ '- ~
<br />An overall grade is calculated as the average grade within the TCMA of ~'~` ~~ t ? ~~ ~ acs
<br />for the three individual grades. The grading system better or worse water ~ ~~~ ~~ ~ - ~ ~ - - ~ - - ~ ~ ~--
<br />allows comparisons of lake water quality across the quality in 2003 as -~ ~-~ - o~ 0""'' `~~'
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<br />TCMA, compared to 2D02 ~, .E ~ ~ CC ~ P
<br />Lakes receiving an °A° are deemed exceptional Furthermore statistical `~~~; - ~ °_ - ° - ~ '~'" t~ ;~ `-~+
<br />compared to other area lakes and have no teen- analysis of the current ". ' ~ ,~„~ "~~r,c~
<br />ational use impairment. Lakes with a "B"grade and historical water .. ® e O O ~ ~~ °n~
<br />teat in:~i cr,~~a _ .. ~... _ :, r -- ~i~, ~~.-,z^u ess ., d
<br />have ve ood water ualit and one modest rec- uali data revealed no ea - ~= ~ ~ =~
<br />r1'9 q Y Y q h' ~,..:r ~~_.. i ~ ~~~~
<br />national use impairment, while lakes receiving a significant trends. There e ~, t~ 0 ~ ~ e '~ 0 , ~ "``
<br />"C"are considered to have average water quality are two factors that are ~ ~ ~,~,,,~ - w ~ i « q ~=~y~~, ~"~'
<br />for the region and an somewhat impaired for rec- likely responsible for _ ~ i -_ _i ~ ~" ~ ~, i~wa'1 ~' ~~' 0"""' ~~ ~
<br />Posted signs like this one at ~ t'° 0 k , ,,,, ~-,
<br />national use. "D"grade lakes have poor water this lack of trends. First, ~Aitcnell take .n Eaen Prairie. I- 0 ®°°t ~ -' ~ l ,,;-~.. ~°;'`
<br />quality and lakes nceiving an "'F"grade have due to the nature of the let lake users know tnat tr,e€; ~ ~~t ~ ~`®`"~°'°~ ~ ~ ~ '
<br />extremeky poor quality compared with other area monitoring program: lake is routinely being monl(or- ~- ~ -~ .. ~ "~^ c.; r~e«~n~ ~-~ r ~ l ~ _ ~ff~ ~-; _.
<br />takes and da not support recreational use, there are frequent gaps ed and assessed. ~, .~ ~..~ .~ ;°~~_ ~..~ ~_ ~~ ~ i~"" ~ ,y t
<br />in the monitoring record. C € ~ ~.t ' ~~miaaq = ' ~ " 0
<br />These gaps adversety affect the ability of statisti- ~" `o f ~ ~A ,'~' ~ ~ p~,~ ,; ~„
<br />cal tests to detect trends. Second, the magrntude } a~ :.,~, ~~ _~_~. t " °'` , r~ t o~
<br />of the poterftiat trends are probably small with m ® J ~7 ~ -- ®~ - r° 0 C~ t
<br />respec4 to the -at• °°al year-to-yep • variability of ~ ~ ""~~~ ~ ~ ~, _ ! _ ~ _ - ~ r ° t
<br />lake water qG lity . o} s l ~ combine the ~ ~Q p ~ ~ ~~!' ~ ~ r,
<br />~ ~° ~ .~~ ~ - r afros th_ d;rtograms, e„~ `~`'~ t ~ ~~,~
<br />r -re ew= a r~mp~t® tea. 0
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