Studies have estimated that during the last 20 years tree cover in urban areas east of the Mississippi River have decreased by 30% while the areas of urban spaces have increased by 20% (www.americanforests.org).  In Allegheny County, development has eliminated or stressed many trees, causing increased stormwater runoff, stream bank erosion, flooding, loss of habitat, and higher air pollutants, among other problems. 

PEC is working with partners Tree Pittsburgh, Allegheny County, and corporate sponsors to develop an Urban Tree Canopy (UTC) Assessment for the county.  A UTC Assessment uses geospatial technology to analyze the tree canopy layer -- the amount and distribution of leaf surface area.  It considers the current size, characteristics, and condition of the trees to help decision makers understand their forest resources and answer questions about where future tree plantings should take place. 

Information gathered in the UTC Assessment and a coordinated approach between public and private stakeholders can protect, maintain, and restore Allegheny County’s urban tree canopy, which will ultimately improve water quality, reduce flooding, and more.  The UTC Assessment should be completed in summer 2011.

Click here for a factsheet on the UTC Assessment for Allegheny County.