I can't tell you how many calls I get saying,
"We just don't have room for grid."
Now there's an answer, Stabilized Aggregate Retaining Wall design.
This design allows you to reduce the embedment depth by nearly half of what you would need with grid. The design and installation are simple! The block acts as your "form" during construction and your increasing the mass behind your wall with open-graded rock (no fines) with a coating of cement that cures and stabilizes the mass.
Here is a cross-section of the Anchor Retaining Wall project http://www.buildingproductscorp.com/ in place, any water that may penetrate the No-Fines zone, would migrate to the perforated pipe at the base of the wall and be removed. 
This project does cost more than just typical Retaining Wall installations, but if you don't have any other option with maximizing space without the use of grid--this system is less costly than the alternatives. (Below is an example of the mix-design any local concrete company could do for you)
If you'd like more information, please contact us at http://www.buildingproductscorp.com/index.php
