ᐅ Cistern in the garden / driveway

rick2018 schrieb:

Even with a 500m2 (5380 ft²) plot, I would rather build a 10,000-liter (2,640-gallon) tank. This way, you can store some water during rainy periods and in winter. Depending on the garden layout, even a small garden uses several square meters per watering.
I don’t mind whether it’s concrete or plastic. It depends on what fits better in terms of size, shape, and price.
I would install an inlet filter with backflush right away. It can also be misused as a fresh water feed.
Choose a pump with sufficient volume and pressure, especially if it’s for irrigation.
Forget about supplying the toilet or similar inside the house. It’s not cost-effective at all (double piping, etc.). Also, the cistern is too small if you want to irrigate. After two to three dry weeks, it will be empty at the latest.

Thanks, Rick. That’s helpful. But honestly, I’m a bit confused because even professionals tell me different things sometimes. So naturally, there’s some uncertainty about what’s the right approach. Would it make sense to maybe talk to the architect?
Originally, I thought about installing a much larger volume, but the specialist shop advised against it because I probably won’t empty the tank, and dirt and debris will accumulate. Plot size: 530
So you definitely wouldn’t recommend using it for the toilet? Even with 3-4 people in the household?

Never connect to toilets.

Bookstar schrieb:

Never connect to toilets.

Why do you say that?

Gets very dirty despite the filter. Economically unfeasible. It only causes disadvantages.

Bookstar schrieb:

Gets very dirty despite the filter. Not cost-effective. It only causes disadvantages.

Thanks!
But basically for the garden?
I want to have the excavation disposed of directly when the preparations for the foundation slab begin.

You can easily empty that.
Let’s say you have 200m2 (2,150 sq ft) of lawn. The water demand for lawn in summer is nearly 20 liters per m2 (2 gallons per sq ft). That means 4,000 liters (1,057 gallons) per week! This doesn’t include hedges, trees, etc. During the establishment phase, you need even more water. So with 10,000 liters (2,640 gallons), you’ll get just under 3 weeks.
An architect usually has no idea about this unless they are a landscape architect.
Believe me, we have several properties in the family with cisterns and automatic irrigation. My sister *complains* that she has only 7,500 liters (1,980 gallons).
I have also helped a few people here in the forum with irrigation planning.
You will get dirt in every cistern. With an inlet filter, less so. Still, you need to have it cleaned out (pumped out) at least every 2–3 years. In a large cistern, this is less of an issue. Always use a pump nowadays with a mid-level water intake.