In the area of North Semarang often occurs tidal floods. The current government has dealt with the flooding of Rob by making dykes on the north coast of semarang. There is a method of handling tidal flooding by making a retention pool, Longstorage equipped with a pump if there is a flood the water is stored in a retention pond then the water is pumped into the river. The purpose of this study is to formulate a correlation between pumps and retention ponds. Alternative flood control using the count of 50 years. The method used is using HEC-HMS. There are three alternatives used in the simulation: 1st alternative pond with an area of 3.8 m3 and a storage volume of 114,000 m3, with inflow of 31.4 m3/s in this alternative the capacity of pump is 30 m3/s, second alternative pool with an area of 4.7 m2 and reservoir volume of 142,000 m3, with inflow of 31.4 m3/s, with pump capacity of 27 m3/s. third alternative ponds with an area of 5.0 m2 and a reservoir volume of 150,000 m3, with inflow of 31.4 m3/s. In this alternative a pump with a capacity of 25 m3/s used.