Question
WE ARE DESIGNING A BUILDING IN A TOWN CENTER AREA WHERE THEY ARE REQUIRING TREE PLANTINGS IN AN AREA BETWEEN MAIN STREET AND THE BUILDING.  THERE WILL BE A 5FT WIDE BRICK SIDEWALK ADJACENT TO THE STREET AND A GRASSY AREA APPROXIMATELY 15 FT WIDE BETWEEN THE SIDEWALK AND BUILDING.  THERE ARE OVERHEAD WIRES APPROXIMATELY 20-25 FT OVER THE SIDEWALK AREA AND A 100 YEAR OLD 10" TERRA COTTA SEWAGE PIPE RUNNING PARALLEL TO THE PROPERTY APPROXIMATELY 10FT OFF THE CURB LINE. WE ARE LOCATE IN MARYLAND.  WE WANT LOW MAINTENANCE AND LOW CLEAN UP (MINIMAL DROPPINGS) HOWEVER THE PLANNING COMMISSION WANTS THE TREES TO SHADE THE STREET.  WE REALIZE THAT SHADING WOULD BE A PROBLEM WITH BOTH THE TERRACOTTA PIPE AND THE OVERHEAD WIRES.  SO, OUR QUESTION IS, WHAT TYPE OF TREES COULD YOU RECOMMEND TO FULFILL THE PLANTING REQUIREMENT WITHOUT CREATING OBSTACLES?

Answer
http://www.jfschmidt.com/utilist.html

Schmidt UtiliTrees?designation is given to trees that are best suited for planting in the restricted zone between street and sidewalk and beneath utility lines. All the trees listed in this link mature at heights that are unlikely to tangle with overhead lines.

These trees have pedestrian-friendly branching, that is compact or vase-shaped to allow for pruning without destroying the shape of the tree. Disease and pest resistant, these cultivars are tolerant of varied soils, climates and urban growing conditions, and require minimal maintenance.

The crabs, cherries, & plumbs can be a bit messy, but have lovely spring flowers and fall colors.  All trees listed have non-invasive roots.  The "least" messy "shade" trees would probably be the Ash or Wireless Zelkova.

Availability will be the challenge for you, as Schmidt is located in the Pacific northwest and anything with 100-year old terra-cotta sewer lines has got to be east coast (you didn't say where you were located)!

Schmidt publishes a SUPER handy guide to plant zones (depends on your location) & sizes.  

http://www.jfschmidt.com/services.html

In the past, I have used their catalog images to convince local municipalities that I have selected the right tree for the right location.

Regards ~M