Espanola Regional Hydro Services Company (ERHSC) Unit: Approximately 3 full time members. This unit represents workers who perform work associated with building and maintaining the hydro-electric infrastructure in the Towns of Espanola and Massey. Our members are linepersons and support staff. The company itself is a wholly owned the towns of Massey and Espanola. The last year has seen drastic growth as the company seeks to provide services in other Northern Municipalities.