Small water reservoirs play important role in rural areas. They used to be very popular, but most of them have been devastated in the last century. It is worth to restore them and to construct new ones. Very small reservoirs (ponds) can be constructed in economical and cost efficient way by individual farmers. In regard to damming below 1.0 m and to reservoirs situated outside protected areas, the permission for construction and the environmental impact assessment is not required. However, one should always keep in mind that even the smallest construction is the work of engineering and should be performed in accordance with the current standards. The increase of available water resources and improvement of water quality demand various measures including those aimed at reducing and limiting water runoff and pollutants transport from the river basins. One of the methods to improve the structure of water balance and the amount of water in rivers is the construction of a large number of small reservoirs, wetland reconstruction etc. Such reservoirs may be divided to: recreational, floristic and faunistic conservation sites, swimming pools, water quality protection (constructed wetlands) and infiltration reservoirs. Reservoirs can have many functions of the economic and natural character. If they are designed and constructed properly they can be a valuable element of the natural landscape in rural areas. Basic data for designing of small reservoirs serving mainly recreational (decorative) purposes and those used for water treatment and ground water recharge are given in the paper.