As expected, Protect Seattle Now, the group that wants to overturn three right-of-way agreements between the city and state on the deep-bore tunnel, has collected enough signatures to qualify for the August ballot. The group collected just over 28,000 signatures, and the city clerk certified 17,329 of those as valid this afternoon at city hall; the measure needed 16,500 signatures to qualify for the ballot.

City attorney Pete Holmes has challenged the proposed referendum in King County Superior Court, arguing that the three agreements, which deal with things like allowing the state to use City Light and Seattle Department of Transportation right-of-way, are merely "administrative" actions to uphold a prior city policy decision to support the tunnel. Holmes has said he wants a ruling on his lawsuit as soon as possible, preferably by May, since the deadline to put a measure on the August ballot is May 24.

However, the  King County Superior Court judge assigned to the case, Laura Gene Middaugh, is married to state Sen. Adam Kline, which could prompt tunnel opponents to ask her to recuse herself. That would represent a temporary setback to the case.

Mayor Mike McGinn has argued that the tunnel agreements are subject to referendum, and has accused Holmes of not "representing the public's interests."