Hello All,
I have an older home on Pasadena. My 2 upstairs bathrooms are not backing up into my downstairs toilet.
Do I call for a high pressure water blast to clean out the obstruction or is there a better way to go?

Thank you

Water blasting's fine as long as there are no vents along the way. Most plumbers use a snake to clear away a blockage.

SPeedball's dead on... find your main sewer cleanout and remove plug... flood system... see if backs out of cleanout... if it does, needs to be snaked from that point.

Can't find the cleanout... then lift downstairs toilet and snake from there.

If hiring somepone to do the work... just see if you can find the cleanout and flood to confirm for yourself that blockage is outside (obviously if does not back up at cleanout and backs up at toilet.. then blockage is between toilet and main drain cleanout).

Hope this helped.