Maryland State House in Annapolis

Maryland lawmakers earned high marks from the Maryland League of Conservation Voters for passing a string of significant environmental laws this year.  But the lofty grades given legislators by the league last week reflect only mixed success in Annapolis for environmental groups amid a deepening party divide on green issues.

The House of Delegates voted "green" 69 percent of the time this year, according to the league's scorecard, while the Senate did so on 63 percent of the key votes.  Each of those scores was the highest in the past four years.

Driving the scores up, no doubt, was passage of several major green bills this year, including doubling of the "flush fee" to upgrade sewage treatment plants, limiting development on septic systems, requiring the state's largest localities to levy fees to control storm-water pollution and banning arsenic in chicken feed.  Environmentalists didn't get everything they wanted, though, as Gov.Martin O'Malley's second attempt at legislation to subsidize offshore wind development and a measure aimed at limiting plastic bag litter failed to get out of committee.  Even the bills that passed got watered down to win votes, the league noted.

The high average scores this year mask wide disparities in partisan voting patterns.  House Republicans sided with environmentalists just 21 percent of the time, while GOP members in the Senate did so on only 8 percent of key votes, a drastic drop from the 34 percent score the year before.

Fifteen senators and 72 delegates scored a perfect 100 percent on the league's annual legislative report card.  Baltimore city's all-Democratic delegation, routinely among the greenest, racked up a 94 percent overall score. 

Eight senators and 11 delegates had perfect "0"s in the scorecard, having voted against the league's position on every key bill. All but one were Republicans, with Southern Maryland Sen.Roy P. Dysonthe lone Democrat to consistently oppose the league's positions.