Yes, Mars did have water, including oceans and rivers, more than 3 billion years ago.
Evidence strongly suggests that the Red Planet was once much warmer and wetter than it is today. While most of this water has disappeared over billions of years, leaving behind only ice (primarily in the polar caps) and trace amounts of water vapor in the atmosphere, past evidence points to significant bodies of liquid water on the surface.
Here's a summary of the evidence:
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Ancient shorelines and riverbeds: Orbital images reveal features resembling dried-up river channels, lakebeds, and possible ancient coastlines. These suggest that liquid water flowed across the Martian surface for extended periods in the past.
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Mineral deposits: The presence of certain minerals, such as hematite and clay minerals, can only form in the presence of liquid water. Their discovery on Mars provides further support for a wetter past.
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Subsurface ice: While liquid water is rare on the surface today, large deposits of subsurface ice have been detected by rovers and orbiters. This indicates that water is still present on Mars, albeit in frozen form.
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Hubble Space Telescope Imagery: As noted by the prompt, images from the Hubble Space Telescope, such as those taken during dust storms, allow scientists to understand the current state of the planet, and by analyzing this and other data, conclude that there was once much liquid water.
Although the exact conditions that allowed liquid water to exist on Mars so long ago are still being researched, the overwhelming evidence points to a past where Mars was a much more habitable planet than it is today.
