Ndi pansi pamadzi tovermill ( madzi otentha ) mankhwala ochiritsira, kuchuluka kwa nthawi yayitali kumaphatikizidwa ndi kukana kwamadzi kokulira pamadzi. Izi zimabweretsa kulimba mtima kwakukulu, komwe kumawonjezera mphamvu yakuthupi ya wodwala.