Take a look at the next bit from the same site, though. I believe this is where mg sees her problem. Canada will accept the documents you posted; the USA has different requirements. Maine rejected the Enhanced Drivers License- no idea about Washington.

"When returning to the United States from Canada, it is very important to note that all U.S. citizens are required to present a valid U.S. passport to enter or re-enter the United States via air. For entry into the United States via land and sea borders, U.S. citizens must present either a U.S. passport, passport card, NEXUS card, Enhanced Drivers License or other Western Hemisphere Travel Initiative (WHTI)-compliant document. The only exception to this requirement is for U.S. citizens under the age of 16 (or under 19, if traveling with a school, religious, or other youth group) who need only present a birth certificate (original, photocopy or certified copy), Consular Report of Birth Abroad, or naturalization certificate."

Good luck, Mary. I hope you can figure out a satisfactory solution.