Solemdal headed into the event buoyed by a fourth-place finish just 24 hours earlier but blew that out of the water with her maiden win.
And she did it in some style, her time of 31:13.4 minutes more than half a minute ahead of Berger.
Despite finishing second best in Austria Berger continued her record of finishing on the podium in every World Cup race this season.
The 15km individual Olympic champion Berger sits pretty atop the overall World Cup standings on 282 points, stretching her lead to 38 with nearest challenger Darya Domracheva from Belarus only managing fifth in Hochfilzen.
Completing the podium in Austria was Finland's Kaisa Makarainen in 31:46.7 minutes, moving up to fifth overall.