Two Port Huron drawbridges will be the subject of annual maintenance this week. The city’s Department of Public works will be power washing on the 7th and 10thStreet bridges starting Monday. Work will be done overnight and both bridges will remain open to vehicle traffic during the maintenance, however drivers can expect occasional lane closures. Work includes scraping and spraying built-up debris from the structure in order to make sure moving parts are working properly. Power washing is expected to be completed by Friday next week.