While government agencies, NGOs, and even commercial entities immediately swing into action to help out, in the case of large disasters, one of the biggest resources – citizens themselves – are underutilized. The rise of social media creates an opportunity for the citizen participation for disaster response management. By harnessing the power of citizen crowdsourcing, the government can have enhanced disaster situation awareness and utilize resources provided by citizen volunteers, resulting in more effective disaster responses. In this paper, the prototype Public Engagement in Emergency Response (PEER) framework is presented. It provides a comprehensive online and mobile crowdsourcing platform for situation reporting and resource volunteering. Events are described that transpired in the aftermath of superstorm Sandy, which demonstrate the benefits of using the PEER framework in a major disaster situation. Also described is how it can alleviate some of the issues associated with the crowdsourcing responses such as fraud.