JR Tohoku shinkansen is the most convenient way to go Iwate prefecture from Tokyo. Get off at Mizusawa-Esashi station, the nearest JR Tohoku Shinkansen stop from the Mizusawa campus. Note that some of Shinkansen trains do not stop Mizusawa-Esashi station.
If you want to go to Mizusawa station, get off the shinkansen at Ichinoseki station, and transfer to JR Tohoku Main Line. The trip between Mizusawa station and Ichinoseki station takes about 25 minutes.
Local bus service is available between the Hanamaki Airport and JR Hanamaki Station. JR Hanamaki Station is a stop of JR Tohoku Main Line. Take the train heading toward Ichinoseki, and get off at Mizusawa Station.
The trip from Hanamaki station to Mizusawa station
takes 30 minutes.
From Akita Airport
Airport Limousine Bus is available from Akita Airport. Purchase a ticket for the Airport Limousine Bus to "Akita Eki Nishiguchi" (JR Akita Station). Note that "Akita Eki Nishiguchi" is not the final stop. At JR Akita Station, take the JR Akita Shinkansen. Then get off at Morioka Station and transfer to JR Tohoku Shinkansen, because most of the Akita Shinkansen trains skip Mizusawa-Esashi Station and Kitakami Station.