The deposit of Lomonosov developed at a trial level, now is at a stage of transition to its fullscale development by the open way. At the same time, first of all, a single open pit is expected to fulfill the diamond pipes of the southern group – Arkhangelskaya and Karpinsky 1 and 2. In this connection the development directed on a substantiation of systems of drainage «big career» and water removals of drainage and other waters were required also. Authors, on the basis of the analysis and generalization of available data, have tried to find the optimal engineering decisions allowing essentially to raise ecological safety of work of given systems at rather low technical and economic expenses.