Medina doesn't have a very large watershed.
In fact it has to rain mostly in and around the town of Medina up above Bandera or the lake will not benefit from even widespread rains, unless it's a flood in that very narrow headwaters.
Back in the early 1900's there were springs that fed into the river, and also creeks that ran just about year round.
Population growth and drought has taken it's toll.
When the lake does come up about every ten years or so, property around the lake suddenly sprouts "For Sale" signs and sales offices spring up on every cross road around the lake.
Back in the early 60's to around the eighties Medina had mostly shanties and land was pretty cheap, but now there are plenty of high dollar homes around the lake as land prices have gone up from people moving here from elsewhere.
The lower the lake gets, the more bargains can be found, but that's if you don't consider a nowhere near full lake a deal breaker.
A neat trick is if you download "Google Earth Pro" there's a time-travel feature which allows you to see satellite photos of lakes from prior years. I got a few screenshots from that for some friends of mine who were thinking of buying land at the upper end of Lake Medina, and that convinced them it wasn't what they were looking for.
