Jalpuja (जलपूजा) is a devotional ritual in Jainism where pure water is offered to the image of a Tirthankara, usually in a temple setting. This act is deeply symbolic. According to Jain philosophy and scriptures:

Jalpuja represents the inner desire to purify one’s soul, just as water cleanses physical impurities. By performing jalpuja with true devotion and right intention (bhava), one practices humility, purity, and detachment.

With respect to karma: Jalpuja itself does not literally "destroy" any specific type of karma. In Jainism, all external rituals—including jalpuja—are considered means to cultivate internal virtues and right attitude (samyak bhava). When performed with pure intentions, such rituals help weaken (kshayopasham) the bonds of pap karma (sinful karmas), especially those related to pride (maan), attachment (raag), and impurity (ashuchi). It primarily aids in purifying the mind and reducing passions (kashaya) like anger, pride, deceit, and greed, which are the root causes of karmic bondage.

Summary: Jalpuja, when performed with true devotion and detachment, aids in the purification of the soul and facilitates the shedding (kshay) or suppression (upsham) of pap karma and passions-related karma (kashaya karma). However, ultimate destruction (nirjara) of karma is achieved only through right conduct, penance, meditation, and self-realization.

Reference: Jain Agamas, Pravachansaar, and Tattvartha Sutra.