Roof runoff water control systems for a building with gutters and a downspout and buildings without gutters. Both systems employ a swale in the ground that is lined with rock filled bags that are opened and laid overlapped end-to-end. For the downspout, a closed bag filled with rock is placed under the downspout with open bags filled with rock laid overlapped end-to-end in the swale and overlapped downstream from the closed bag. For a building without gutters and having a drip line in the ground, open bags filled with rock are laid overlapped end-to-end in the swale. The swale and the open bags are aligned with the drip line.