The present paper shows the change process in seven third order channels, tributaries of the Paquequer River, where is located Teresópolis city. The space perspective, considering punctual situations along the longitudinal profiles and the historical perspective, considering modifications along 41 years (1956-1996), were analysed.

For the spatial analysis, the alterations were evaluated in the geometry, considering the variables collected in the field: width, medium depth of the channel, medium depth of the channel in the water level, channel capacity, wet cross section area, wet perimeter, hydraulic radius, basin area, medium velocity of the flow and discharge. The channel balance was defined by the relationship between the channel capacity and the respective basin area.

For the temporal view, the growth of the impermeable areas was analysed, through aerial photographs, 1956 (1:33.000); topographical map of Teresópolis, 1966 (1:50.000); aerial photographs, 1976 (1:40.000); satellite image SPOT, 1996 (1:50.000). The channel beds were reconstituted through aerial photographs, 1956 (1:33.000); municipal plans, 1971 (1:2.000) and aerial photographs, 1994 (1:8.000).

The seven third order channels showed narrowing in different points of the longitudinal profile, with consequent channel capacity decrease. Increase of the impermeable areas in the basin was verified due to the urban growth, during 41 years. In 1996, the percentage of impermeable area ranged from 11,81% (basin of Paquequer Pequeno) to 53,80% (basin of Meudon), with consequences to the drainage net, such as covering of the rivers by galleries, alignment of buildings, bridges and houses.