The phrase "walk upstream" is correct and usable in written English.
It means to walk in the opposite direction of the current or flow of a river or stream. Example: The hikers decided to walk upstream to reach the waterfall, as it was easier to climb up the rocks from that direction.
Return to the south bank, walk upstream or downriver and you might reach Dilston Grove, at the south-west corner of Southwark Park.
In summer, we swim up and down but in the winter we walk upstream and have a float down with the current.
Head south on Camino del Rio, park at the Durango Visitor Center (111 South Camino del Rio, 800-525-8855), waboutpstream about 100 yards along the bike path and look for the small crowd gathered at Smelter's Rock for a front-row view.
Decision time: If I headed downstream I could make a 6.5-mile loop on opposite banks of the river; but an easy 2.5-mile walk upstream on the west bank trail would take me to what the day-hike guide described as the beautiful springs that emerge near Canyon Creek Campground.
The following nested primers were used to walk upstream; 5'GGGTCCTTCTCGTTGATGTGCC3', 5'TCGTTGandTGCCCGTTGCC3' and primers used to walk downstream were; 5'TGGGGATCAGCCAGGGCAAG3', 5'CAAGCCGCTGCCCATCAACA3'.
Primers used for the P. coffeae fragment were Pc-eng1-up1 (TTGGAGTCAATGGCCCGGATGG), Pc-eng1-up2 (GATGTTCGGATTGGAGCCATATTGC) to walk upstream en Pc-eng1-down1 (TCAAATCTCTGCTACACTCTCCAC) and Pc-eng1-down2 (CAAACAATCCCTCAGGGATAAGGC) to walk downstream.
I walked upstream, drifted my fly over it and was connected to a bright 13-pounder.
As students poured out of the school, Saujani, walking upstream, made her way to the fourth floor.
I walked upstream, where the river deepened and slowed, and tied on a fat, rubber-legged stimulator with a tomato-red belly.
Trying to hail a cab, I walked upstream from an intersection where other people were already waiting and intercepted one before it reached the corner where I'd been standing.
In less than a half hour I landed four large fish-one more than eight pounds-and began walking upstream to look for new water.
