This interview is a historian-informed reconstruction based on archaeological evidence from Lake Zóñar in southern Iberia and the Lamasba water allocation inscription. Cassia Hydria is a composite character representing the class of water rights traders who emerged during Roman water scarcity in the 2nd-1st centuries BCE. The legal frameworks, allocation systems, and drought conditions described are documented in the archaeological record.
I meet Cassia in what passes for her office: a covered portico overlooking the forum in Corduba, where she can watch the water clock that governs half the commercial transactions in southern Iberia. She's counting something on an abacus when I arrive. Doesn't look up. When she finally does, her expression suggests she's already calculated exactly how much of her time this conversation will cost.
You trade water rights. How does one even begin doing that?
My husband did it first, if we're being honest. He was a grain merchant who got clever during the dry years. Noticed that farmers were desperate for irrigation time slots in the Lamasba allocation system, but the system was rigid. You couldn't just sell your water rights outright. But you could lease your land with the water rights attached. Or you could arrange what he called "temporary transfers of cultivation rights."1
He died of fever three years ago. Left me the contracts and a reputation for being ruthless, which I've maintained. Turns out widows who act helpless get cheated. Widows who act like they'll bury you in legal documents get paid on time.
The Lamasba system allocates water based on trees cultivated. How do you make money from that?
The system was designed beautifully, actually. Probably by someone who genuinely cared about fairness. Each landowner gets water time proportional to their olive trees. Small farmers with twenty trees get twenty units of time. Large estates with two hundred trees get two hundred units. Very egalitarian.2
She adjusts something on her abacus
But here's what they didn't account for: what happens when a small farmer's trees die in the drought, but he still needs water for his grain crop? Or when a wealthy estate owner has more water time than he can actually use because his irrigation channels can't handle the flow rate?
That's where I come in. I match surplus to scarcity. Take a percentage. Usually twenty percent of the water time value.
Some people call it profiteering. I prefer "liquidity provision," but I'm not precious about it.
You're profiting from drought. Does that bother you?
She laughs, but there's no humor in it
The drought is happening whether I'm involved or not. Lake Zóñar is turning into a salt flat. The springs that used to feed it are being captured for Roman settlements because apparently senators need their bath houses.3
I didn't create the scarcity. I just facilitate transactions that help people survive it. The small farmer who can sell his unused water time because his trees died? He can buy grain with that money. Feed his family. Without me, he just has a useless legal right to water he can't use.
Pause
But yes. Some nights I lie awake thinking about the estate owner who bought up water rights from three desperate families and now controls enough irrigation time to green his entire hillside while his neighbors' crops turn brown. I facilitated that transaction too. Took my percentage.
The moral calculus gets complicated quickly.
The Roman legal system protects water rights as servitudes attached to land. How do you work around that?
I don't work around it. I work within it, which is the only reason I'm still in business instead of exiled. The servitude system is actually quite sophisticated. Water rights transfer with land ownership, and they're protected even against wealthy neighbors trying to pressure you.4
What I do is arrange temporary cultivation agreements. You keep your land, keep your legal water rights, but you grant me temporary cultivation rights to specific parcels. The water time flows to whoever is actively cultivating.
It's all legal. Mostly.
The magistrates don't love it, but they can't actually stop it. And honestly, some of them are my clients. Turns out Roman administrators also like having reliable irrigation for their villa gardens during droughts.
What's the strangest transaction you've arranged?
She grins for the first time
Last year, a wealthy widow wanted to grow roses. Roses. During the worst drought in twenty years. She had water rights attached to her olive grove, but she'd let the trees die and planted roses instead. Technically illegal, but she was well-connected enough that no one was going to challenge her.
Problem was, roses need water at different times than olives. The allocation schedule didn't match her needs. So I arranged a swap with a grain farmer two valleys over. His late-summer water time for her early-spring allocation. Both got what they needed. I got twenty percent of the value from each.
The absurdity of it still gets me. People are eating bread mixed with acorn flour, and I'm facilitating rose gardens for bored patricians. But that bored patrician paid in actual silver, which I used to buy grain for my household and three families who work for me.
She shrugs
You see what I mean about the moral calculus.
You mentioned Lake Zóñar turning into a salt flat. What's happening there?
It's eerie if you go see it. There are Roman burial sites that are now five meters below the current water line. Except the current water level is so low you can walk to them.5 My grandfather says the lake used to be deep enough for boats. Now it's shallow and saline. You can see gypsum crystals forming at the edges.
The Romans captured the springs feeding it. Needed the water for Corduba and the new settlements. Can't really blame them. Cities need water. But the lake is dying. The farmers around it are struggling. And everyone pretends this is temporary, just a bad drought cycle.
That's the thing about water trading. I'm helping people adapt to a crisis we created. It feels productive. I'm solving problems, matching resources to needs. But I'm also making it easier for the system that caused the crisis to continue.
If water trading wasn't smoothing out the scarcity, maybe people would be forced to confront the actual problem.
Which is?
We're taking more water than the land can provide. The Roman settlements, the expanded agriculture, the bath houses, the fountains. It all requires water the region doesn't naturally have enough of, especially during dry cycles. But admitting that means admitting we might need to leave, or change how we live, or accept limits.
Water trading lets us pretend we can manage the scarcity indefinitely.
She's quiet for a moment
And maybe we can! Maybe I'm wrong and this is just a dry period and the rains will return and Lake Zóñar will refill and everyone will forget this ever happened.
She doesn't sound convinced.
Do you think about leaving?
Where would I go? I've built something here. I understand the legal system, I know the players, I have contracts and relationships and a reputation. Starting over somewhere else means being nobody again. Being a widow with no husband's name to trade on, no established business, no leverage.
And honestly, as long as there's scarcity, there's money in water trading. I'm probably one of the last people who should leave.
Long pause
I'll be profitable right up until the moment the whole system collapses.
That's not a comforting thought, actually.
What advice would you give to someone in a similar position?
She laughs sharply
Don't ask me for moral guidance. I'm the person who charges twenty percent to help you not die of thirst.
But practically? Understand the legal system better than anyone else. Keep meticulous records. Never cheat on a contract. Your reputation is everything, and in a crisis, people remember who dealt fairly.
And maybe set aside some of the profits for when the crisis ends. Or when you need to leave. Or when the moral weight of what you're doing catches up to you.
Also, don't feel too guilty about taking your percentage. The crisis is happening anyway. You're not causing it by participating in it. But don't fool yourself into thinking you're solving it either. You're just making it more efficient. Which might be worse, depending on how you look at it.
She turns back to her abacus
Now, if you'll excuse me, I have a meeting with a farmer who wants to sell his spring rights before the season ends.