POST FALLS, Idaho. - The spill gates at the Post Falls Dam have been open for the past week, causing the park to close. But Avista announced that the spill gates will close at 9 am on Wednesday morning. The park will open as well at that time. When the spill gates are open at the Post Falls Dam, no one can be on the river or on the beaches from the Spokane Street Bridge to the Post Falls Dam. Avista thinks that after the spill gates are closed this time in late June, it will not have to open the spill gates for the rest of the summer. Of course, that all depends on the weather.