▁ ▁Loc ated ▁in ▁the ▁small ▁park ▁L ills jö par ken ▁and ▁surrounded ▁by ▁heavily ▁tra ff icked ▁ar tery ▁roads ▁on ▁all ▁sides , ▁it ▁is ▁rich ▁in ▁nut ri ents ▁with ▁high ▁levels ▁of ▁met als ▁in ▁the ▁sed iments . ▁ ▁Pro spect s ▁are ▁to ▁improve ▁the ▁water ▁quality ▁to ▁keep ▁the ▁lake ▁as ▁a ▁locale ▁for ▁birds . ▁ ▁C atch ment ▁area ▁ ▁L ills jön ▁is ▁a ▁small ▁and ▁shall ow ▁lake ▁connected ▁to ▁Ul vs und as jön ▁through ▁a ▁channel , ▁and ▁the ▁flow ▁is ▁period ically ▁revers ed ▁with ▁water ▁pour ing ▁into ▁the ▁lake . ▁ ▁Half ▁of ▁the ▁catch ment ▁area ▁is ▁composed ▁of ▁forest ▁and ▁open ▁terrain , ▁part ▁of ▁series ▁of ▁par ks ▁const itut ing ▁a ▁local ▁recre ational ▁resource . ▁ ▁He av ily ▁tra ff icked ▁roads ▁take ▁up ▁some ▁ 4 ▁per ▁cent ▁and ▁settlement s ▁( including ▁all ot ment - g ard ens ) ▁approximately ▁ 2 0 ▁per ▁cent ▁of ▁the ▁surface . ▁ ▁The ▁lake ▁is ▁considered ▁as ▁of ▁great ▁recre ational ▁value ▁but ▁of ▁moder ate ▁natural ▁importance , ▁except ▁as ▁a ▁bre eding ▁locale ▁for ▁many ▁fish ▁species ▁in ▁Lake ▁M ä lar en . ▁ ▁Motor bo ats ▁are ▁prohib ited ▁in ▁the ▁lake . ▁ ▁The ▁lake ▁is ▁surrounded ▁by ▁the ▁decid uous ▁forest ▁and ▁la wn s ▁of ▁the ▁park ▁L ills jö par ken . ▁ ▁Three ▁all ot ment - g ard ens