Born in Kathmandu, Nepal, Dr. Shrestha graduated in Civil Engineering with Honours from the University of Roorkee (now Indian Institute of Technology, Roorkee, India) in 1985, followed by Master of Engineering and Doctor of Engineering degrees from Asian Institute of Technology in Bangkok, Thailand, respectively in 1987 and 1991, specializing in large-scale water resources development planning. He was among the recipients of Robert McNamara Fellowships 1991-92 cycle of the World Bank for post-doctoral research in Nepal, India and Thailand.

His professional work experience expands over 35 years covering a wide range of functions. In the first leg of his career, he worked as a civil overseer, civil engineer, water resources expert, research associate and project team leader/coordinator.

He joined UN High Commissioner for Refugees (UNHCR) in 1994 as Programme Officer (Engineering) in Jhapa/Nepal, and later was deployed to its emergency operations as Field Officer in Cambodia and Programme Officer in East Timor. In his over 26 years with UNHCR, he served for 10 years as Senior Water and Sanitation Officer in its headquarters in Geneva, Switzerland, until year 2010 and subsequently assigned to its field locations as Head of Field Offices in Maungdaw/Myanmar (2010), Salloum/Egypt (2012), Alexandria/Egypt (2013), and Head of Sub-Offices in Quetta/Pakistan (2015) and Peshawar/Pakistan (2018). He travelled extensively in countries across Africa, Asia, Middle-East and Europe providing technical supports to its operations in the field and participating in emergency preparedness and response missions, including Syria, Jordan and Saudi Arabia during the second gulf war in 2003, Banda-Ache/Indonesia during the Tsunami disaster in 2005, Dadaab refugee camps in Kenya for rehabilitation of flood affected areas in 2009, and Alexandria in Egypt managing influx of Syrian refugees in 2013/14. While assigned in the HQ, Geneva, he served as a member in inter-agency humanitarian forums and technical committees, and as a resource person for different training activities. He retired from UNHCR in mid-2022.

Throughout his professional career, he participated in several international conferences and had published over 15 research/technical papers and articles in international journals and conference proceedings in the domain of water resources development planning and WASH in humanitarian operations. Currently, he is engaged in social services and initiated philanthropic activities aimed at empowering marginalized communities and conservation of natural resources. Since 2012, he is a member of Rotary Club of Yala, RI District 3292 (Nepal and Bhutan).