If there is one specific “rain garden tool” I always carry with me for both the design and installation of a rain garden, it is a water level.
This $20 DIY tool is waterproof, does not require batteries, and has kept my $500+ laser level on the shelf for most of this year.
(Approx. 20 minutes; Skill Level = Easy)
Drill 1/8″ hole at 18″ and 1″ on Ruler.
Drill holes in second ruler.
Run snow markers through the zip-tie loops.
Secure tubing, ruler, and snow marker with zip-tie; tubing on the numbers side.
Rotate tubing to unwind slack.
Water should be level. Make sure all air is out of the lines.
Enlarge holes with 9/32″ bit.
Insert zip-ties through holes and pull only a for few clicks.
Run tubing through the zip-tie loops.
Secure second tube, ruler, and snow marker.
Fill with water to 18″. A hose works too.
Put in rubber tops for storage and transport.
Ready to go!