Two fish habitat projects will clog roads this weekend in order to open up area rivers to salmon and other species. One is on SR 900 between Renton and Issaquah. The other is under SR 202 in Woodinville near 522.

Little Bear Creek is important to fish habitat, but the old culvert under SR 202 can make it nearly impossible for them to swim through. It can flood, sediment can block fish, and the rivers themselves have even changed course. It's especially important for species of salmon in the Sammamish River system, some of which are listed as threatened under the Endangered Species Act.

"Fish passage and healthy streams are important to the entire Northwest and having healthy fish runs. Both of these projects will contribute to that as part of the long term goal to improve the health of all of these streams," said WSDOT spokesperson Kris Olsen.

The projects will create much bigger spaces for water to flow and fish to swim. In Woodinville, an underground bridge will open up fish passage but close up passage for drivers over the weekend.

"Bridge columns we've already drilled into the ground," Olsen said. "They weigh 50,000 lbs a piece, and we've got 20 of those to set. So, we're going to have to dig a huge hole in the ground."

The section of SR 202 between the 522 ramps and NE 177th Place will close for the weekend starting at 10p .m. The section SR 900 will close between Renton and Issaquah starting at 7 p.m. Friday. They will both reopen Monday, July 31 at 5 a.m.

Drivers should expect delays; some could add an extra hour to travel.