A dissertation submitted in partial fulfillment of the requirements for award of the degree of Master of Science in accounting and finance of Mzumbe universityFinancial management practices is the key role for self sustainability on donor funded water projects, and in Tanzania is the factor which undermine efforts for sustainability. Ability to pay to meet cost is the key essential issue in assuring sustainability. The main objective of the study is to assess the financial management practices specifically the inefficiencies in donor funded water projects to support self sustainable, which eventually will help water entities to achieve sustainability To archive expectation, case study approach was used as means of study. GWI phase one implementation area used as a focal point. Interviews and questioner were used to collect primary data, while secondary data were collected by reviewing butch of documents used in implementation as mean of validating of primary data. SPSS software was used to analyse data which helps to present in form of table and figures which are easy to understand. Issues such as integration between financial planning / monitoring and organization strategies, preparation and sharing of financial information, level of streamlining revenue and source of income were among of financial management related indicators which ware scrutinized. Among of major findings, evidence shows that 65% of executives do not produce financial report decision are based on knowledge and not on reports presented. Revenue collection was weak by 74.7%, slightly improved by the kind of technology deployed where deep well scheme is contributing positive by 65%. The report emphasises the need for pricing based on achieving full cost recovery. To share findings exhausted from this research the most policy implication advice is to look water problem from financial management best practice perspective. Let’s make people accountable on their act or omission which causes non functionality of the water sector, people mast pay based on the value of water. Currently water is not as free gift from god. Also let’s make people understand water entities the same as other business which are driven by surplus .