  To date, few studies have focused on protostellar outflow feedback at scales
larger than several parsecs. To address this paucity of research, we
investigate the effects of feedback from CO outflow candidates on their parent
clouds over $\sim$ 110 deg$^2$ toward the W3/4/5 complex and its surroundings.
Our search identified 265 $^{13}$CO clouds with radii being $\sim$ 0.04 --
17.12 pc. We estimate the turbulent support and potential disruptive effect of
the outflow activities through analyzing physical properties of outflow
candidates and their host clouds in terms of turbulence and gravitational
binding energy. We find:(1) clouds of larger size might be less affected by
feedback; (2) the possible scale break is $\gtrsim 4.7$ pc for both turbulent
support and potential disruptive effect; (3) if outflows couple to dense gas
where stars are forming, for clouds in the Perseus arm, a scale $\lesssim$ 0.2
-- 0.4 pc is sufficient for the energy and momentum injected by outflow
activity to maintain turbulence, while for clouds in the Local arm, the scale
is $\lesssim$ 0.1 -- 0.2 pc; and (4) for clouds in the Perseus arm, a scale
$\lesssim$ 0.3 -- 1.0 pc is needed for outflow activity to potentially disperse
material away from the natal clouds, while for clouds in the Local arm, the
scale is $\lesssim$ 0.2 -- 0.6 pc.The strength of outflow activity may affect
the values in the points (3) and (4). Finally, we find that outflow feedback
probably possesses the power to alter the linewidth-size relation.
