I understand that hwy 530 is open to one lane of alternating travel.
With the floods and low chum runs the numbers of Skagit eagles is down from what they were a couple decades ago. That said photographers I know are finding some birds.
An alternative for your mother might be a day trip on the Skagit/Samish flats. Likely to find swans, eagles, snow geese, various duck species, shore birds, ravens, owls, hawks and other bird species. A good place to start would be Fir Island near Conway. There are a number of eagles (adults and Juveniles) on the Island and with up to 5 eagle nests on the Island some of the birds are doing housekeeping (packing stick for their nest. They will be laying their eggs later this month and may see a pair around the nest with one "sitting" on the nest. In a couple months the adults will be bring food to the hatchlings. On Fir Island there are several public access areas where a short walk will put you in some viewing areas. Skagit Headquarters, the Snow Goose reserve, Jensen access and North Fork access are a few.
Going north from Fir Island along the Best road to hwy 20 and then northward to Bayview and Edison areas will also put one in prime bird viewing areas.
While there are no steelhead opportunities int he area there are several nice places for lunch. Over the next 3 months or so there is enough and variety of opportunities to merit monthly visits.
curt