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We report a multi-epoch, simultaneous 22 GHz H2O and 44 GHz class I CH3OHmaser line survey towards 180 intermediate-mass young stellar objects,including 14 Class 0, 19 Class I objects, and 147 Herbig Ae/Be stars. Wedetected H2O and CH3OH maser emission towards 16 (9%) and 10 (6%) sources withone new H2O and six new CH3OH maser sources. The detection rates of both masersrapidly decrease as the central (proto)stars evolve, which is contrary to thetrends in high-mass star-forming regions. This suggests that the excitations ofthe two masers are closely related to the evolutionary stage of the central(proto)stars and the circumstellar environments. H2O maser velocities deviateon average 9 km s^-1 from the ambient gas velocities whereas CH3OH maservelocities match quite well with the ambient gas velocities. For both maseremissions, large velocity differences (|v_{H2O} - v_{sys} | > 10 km s^-1 and|v_{CH3OH} - v_{sys}| > 1 km s^-1) are mostly confined to Class 0 objects. Theformation and disappearance of H2O masers is frequent and their integratedintensities change by up to two orders of magnitude. In contrast, CH3OH maserlines usually show no significant change in intensity, shape, or velocity. Thisis consistent with the previous suggestion that H2O maser emission originatesfrom the base of an outflow while 44 GHz class I CH3OH maser emission arisesfrom the interaction region of the outflow with the ambient gas. The isotropicmaser luminosities are well correlated with the bolometric luminosities of thecentral objects. The fitted relations are L_{H2O} = 1.71 * 10^{-9}(L_{bol})^{0.97} and L_{CH3OH} = 1.71 * 10^{-10} (L_{bol})^{1.22}.

A Multi-Epoch, Simultaneous Water and Methanol Maser Survey toward Intermediate-Mass Young Stellar Objects