Josh Ellis

At 215k miles, you might as well replace the calipers too while you're bothering with this effort.  You should be able to buy "fully loaded" calipers which already have the new pads in there which will save you a bunch of labor and increase the quality of the finished product considerably (if you don't know what you're doing when replacing the pads).  Fully loaded calipers + rotors and you're done.

If you do that, THEN you'll need to bleed the brakes.  You normally do not need to bleed brakes when simply replacing pads, and actually if you screw with the fluid level before you replace them (i.e., top-up the fluid then replace pads) you will overflow your reservoir and make a mess because a ton of fluid is stored in the always-out pistons ("always out" due to the warn pads).  When you push the pistons back in to make room for the new, thicker pads (which can be non-trivial, another reason to just buy a new caliper) all that fluid goes back into the reservoir.
This is all to say that the fluid level in your master cylinder is actually a proxy for how warn your pads are all around the car.  If it's been a long time since you've done your pads and your fluid low light comes on, you probably just need to change your pads (and NOT add more fluid) because all that fluid hasn't "leaked" but is actually stored in each "nearly maxed out" piston.  The brakes are one system where a leak will be VERY, unavoidably obvious.

Ron,
You've been given lots of great information already.    Keep in mind that context is INSANELY important here, a place with an average rainfall event of <0.25" on a regular basis has much different infiltration needs than one with 0.5-2" a few times a year.  Soil type obviously plays an important role: if you have eolian blow sand like much of Southern Utah where I live then keylining is pretty functionless, if you have heavy compacted clay it can drastically improve infiltration.

All that said, I recommend that you reach out to Chris Gill, he's keylined thousands of acres of creosote scrub down south of El Paso.  He swears by it in your region and says he has disrupted the creosote monoculture and gotten actual grasslands back using the technique.

He did a presentation at the Quivira Coalition conference a few years ago, here's a video he showed about his use of keyline on his 32,000 acre ranch:
http://circleranchtx.com/keyline-101-video/

There should be NRCS funding available to help offset the cost, check with your local office.  Again, Chris might have some good contacts with you on this front.  He also owns a plow that he might let you borrow!

As an aside, if you are interested in regenerative ag in this region I HIGHLY recommend attending the Quivira Coaltion conference in ABQ in November.

Good luck,
~Josh
Boulder, Utah