as dull as ditchwater
dull as ditchwater
as dull as dishwater
dull as dishwater

For all you care, they may be as dull as ditchwater."

The 40 works of art chosen for it are generally as dull as ditchwater.

Why, the very air is as dull as ditchwater!

A most estimable young woman and as dull as ditchwater, but he thought the world of her.

He's not as dull as ditchwater.

Were it not for the ill tempers and that goal it would have been as dull as ditchwater.

"Hmmm, it was as dull as ditchwater without our warriors and young ones about.