New York City has made leaps and bounds toward sustainability since the last Earth Day, when Mayor Bloomberg launched PlaNYC.  The administration and City Council have helped reduce greenhouse gases, manage storm water, plant trees and curb emissions from taxis and black cars.

But there's no guarantee that the next generation of elected leaders will keep the momentum going.  That's why it's critical that the city lock in permanent reforms in the next 20 months. 

Take climate change.  Last year, the City Council passed legislation seeking a 30 percent reduction in greenhouse gas emissions by 2030- an ambitious law and the first of its kind on the local level.  But exactly how that goal will be achieved remains to be seen. One important step we can take is to codify energy conservation measures such as requiring libraries and museums to use heat and light more efficiently. 

Albany frowned on congestion pricing (for now), but the heated debate has one very positive outcome: commuters are looking to our elected officials to solve the dilemmas of traffic congestion and overburdened mass transit.  And there is a lot more to sustainability than getting cars off the road.  New York produces over 20,000 tons of solid waste a day, and recycling is not emphasized enough.

We can also improve upon PlaNYC by broadening its scope.  If the city made a concerted effort to create a "green jobs" corps, it would create well-paying, skilled work and drive innovation in energy efficiency and the "clean tech" sector as well.  

This Earth Day, our environment is on more solid footing thanks to a commitment by our leaders.  Let's make sure we can say the same thing in the years to come. 

Marcia Bystryn is president of the New York League of Conservation Voters.