(Portland, OR) -- The first public hearing on spending up to 500-million to treat Portland's water for a parasite will take place today. The Portland Utility Board will hold the hearing from 4:30 p.m. to 6:30 in the Portland Building. It's the first time residents will be able to speak on spending the money on a parasite that has not yet proven to be a problem. The Oregon Health Authority determined that the city must comply with federal requirements. The city council will have to make a decision by August 11th, on whether to spend 105-million to treat the parasite by ultraviolet light, or up to 500-million on a treatment plant that would also control other contaminants.