Issue 2/2017 of Ecology & Infrastructure magazine, with which TLL Media publishing house will participate in this years edition of the international exhibition Water Sofia, is focused on water treatment. The main topic is "Variable speed wastewater pumping ", which acquaints readers with engineering solutions for operating wastewater pumps at a reduced capacity in order to optimise performance and cut operating costs. The edition also features the sequel of the article from the last issue of the magazine - "Dosing pumps for water treatment plants". In the commentary piece two of the leading companies in the market - Adara Engineering and Hennlich, present their latest products and solutions. Also of interest is the feature in the"Business" section of the magazine, realized in cooperation with the Ministry of Environment and Water, which presents opportunities for the municipalities to build composting plants with European funding.