RICHMOND, Va. (WRIC) -- Richmond Mayor Danny Avula provided an update on the city's water treatment plant restoration efforts as the fourth day of the boil water advisory continues. Avula spoke around noon on Thursday, Jan. 9. A video of the press conference is available in the video player of this article. Avula said the city's water reservoir had filled to 18 feet, allowing full water pressure to resume. Though residents should soon see water service return if they have not already, he reminded residents that a boil water advisory is still in effect. ALL COVERAGE: Richmond Area Water Crisis "I'll start with the great news, which is that our system now is fully pressurized in all nine zones," he said. Now that the system is fully pressurized, Avula said the water will be tested for bacteria, and then another test will be completed 16 hours later. If both of those tests are negative, he said the boil water advisory will be lifted. (Photo: Mark Morales, 8News) "If all goes well, we should be able to do that tomorrow or early Saturday," Avula said in regard to the timeline of lifting the boil water advisory. Regarding the winter storm expected to impact Central Virginia over the weekend, Avula said additional personnel will be on hand at the city's water plant, including mechanics, technicians, electricians and engineers. In addition to increased staffing, Avula added that the generators and battery backups were tested at the plant ahead of the winter storm. "Another thing we want to do is share a little bit about planning as we head into this next weather event," Avula said. "A few of those things that we have been doing: testing battery backups, making sure that the generators are working, increasing staffing and surveillance roles at the plant to minimize the impacts if we do have another outage." (Photo: Mark Morales, 8News) When asked about how and when residents would be billed for water services in January, Avula said city officials have decided that billing would be postponed, though he said additional information would be forthcoming. City officials added that water would continue to be distributed to the public on both Thursday, Jan. 9 and Friday, Jan. 10. This comes after an update from the city earlier this morning reported that the city's water reservoir had filled to 17 feet overnight -- the maximum fill being 18 feet. Additionally, officials reported that eight zones at the water treatment plant had been brought back online. This is a developing story, stay with 8News for updates.