Husnain has been associated with WAPDA for over 15 years, gaining deep insight into the water challenges faced by Pakistan. These challenges include limited focus on conservation, water-intensive agricultural practices, inadequate storage infrastructure leading to water, food, and energy insecurity, excessive groundwater extraction, and interprovincial disharmony caused by irregularities in water accounting and auditing systems. He has also observed the complexities of transboundary water disputes. During his tenure at WAPDA, he has held several key positions, including roles at the Tarbela dam, the 1410 mw Tarbela 4th extension hydropower project, the Simly dam project, and within WAPDA's planning division