Among the reasons of historical fame of Gonabad is its long history in constructing qanats and endeavors to keep and exploit them for agriculture and horticulture in this desert region. Taking a descriptive-analytical approach and relying on the documents of Astan Quds Razavi, this study examined the taken measures for keeping the fruitfulness of a number of endowed qanats of Gonabad from Safavid to Qajar period. This study sought to answer the questions: How much did the trustees of Astan Quds Razavi pay attention to dredging as a significant act to maintain the endowed qanats of Gonabad? What measures and factors were required for and optimal dredging? The results showed that despite the ups and downs over the past centuries, Astan Quds Razavi as the trustee of a number of qanats of Gonabad had considered and done dredging the qanats to maintain the agriculture of the region and make the ground for providing the locals’ livelihoods. Moreover, by accepting the dredging operation of qanats as a specialization, the organization has considered providing financial capital, sufficient time, employing specialized manpower, and providing needed tools and equipment. However, some factors have been affecting the level of dredging, the way of performing, and the outcomes, including the political situation of the region at that time, the way of performing the conventional work structure for dredging qanats by skilled and experienced well diggers, the level of providing necessary expenses for wages and materials, and the quality and number of needed instruments and facilities.