Designing water systems with natural spring on property

I have a 3000m^2 plot for a family of 4 homestead in Indonesia. First things first, design WATER. There is no municipal grid water, we are in a remote area. A spring/'stream' borders the back end of our rectangle-ish plot. The rectangular plot is mostly flat, until it slopes down in the back of the land to the spring / “stream”.  Some of the slope is rather steep, some is gentle and can easily walk to the spring. On our property, the stream is currently not flowing but it’s still wet. Just a few meters downstream the water is fully flowing, and actually channeled and used by neighbor farmers to irrigate rice paddies. Neighbors say it flows year round. BUT water doesn’t flow up, so alas, to utilise it we will have to pump it.

I don’t think directly pumping water from above ground downstream is reliable, and potentially not clean given the surrounding agricultural runoff and the dirty plastic dumping from local homes everywhere.

Currently I am thinking to drill a well near the spring/’stream’, and I assume I won’t have to drill too deep. I will also calculate how big of a rain tank we can have to collect water off the house roof on the flat land. I am thinking to use the pumped well water mainly for the garden irrigation, and the harvested rain water for the drinking water.

Sumatra is a rainy tropical climate, although it does get dry mostly June-September.

As you can see, the plot is empty, so I am designing for water and will next need to choose a location for the house, and consider access through the property, etc. It is cut off in the picture, but the government road directly borders the end of the property opposite the stream.

Looking for any advice or stand out issues you may notice in my thinking!

Interesting project.
I deal with water. Look at my signature.
Some questions first;
- what size roof do you plan to have?
- what rainfall do you have annually?
- what crops and water consumption are you hoping for?
- Is the road at the bottom o fthe photo?
- Will any sun land in your garden?
- Where is north in the photo?
- Is there local power or do you make your own?

Thanks John.

I don't have building plans yet... But lets say 260m^2 maximum is allotted for 2 story house + shed space. so Maybe then 13x20 or less.
2500-3000mm per year rainfall
Crops: Focus on market garden for restaurant - mainly leafy greens and annuals. I will set up alley cropping with small fruit trees/bananas in the tree lines.
Water consumption for the market garden plus the family - 2 adults 2 kids, showering/drinking/washing up, etc.
Yes road is at bottom of photo right where it is cut off.
There is plenty of morning sun in garden, and protected from afternoon sun heat.
North is the top left corner, south the bottom right corner.
There is local power.

John C Daley wrote:Interesting project.
I deal with water. Look at my signature.
Some questions first;
- what size roof do you plan to have?
- what rainfall do you have annually?
- what crops and water consumption are you hoping for?
- Is the road at the bottom o fthe photo?
- Will any sun land in your garden?
- Where is north in the photo?
- Is there local power or do you make your own?

Holly, we have a spring that comes out of a vertical pipe,  that uses gravity flow to all parts of the property.  

Sounds like the spring water is just bubbling out of the ground?  The spring hasn't been developed, as in there is a pipe in the ground it's coming out of, or it's flowing into a man-made reservoir?  Check out YouTube for various ways to develop a spring, including creating a small reservoir with underwater concrete and/or vertical pipes and a spring box.  

If there is any way you can get the spring water to flow through pipes into a good-sized water tank, then pump from the tank.  That is cheaper and has less maintenance than a well.

What is the elevation change from the blue lines (spring area) to where you have the number 10?  

Just in case, do you have water rights to that spring?  Is it flowing downstream where others use that water for a pond, their drinking water or their agriculture?  Even if you have rights, it might be the neighborly thing to do to make sure others relying on it downstream still get something from it.

House:  Usually houses are built where there is bedrock near the surface so you have a solid base for the foundation.  You wouldn't want it too close to the spring area since you don't want wet soil under your house, so the highest part of the parcel hopefully would be the driest soil.  Do you want to take advantage of passive solar heat coming in large windows that face the sun most of the day?

Driveway:  Driveways are expensive to maintain with gravel, so the shorter, the better.  Struggling with a driveway in soil that is wet because of the spring would require underground drainage.  

So you may have about 78,000L of rainfall per year.
That is a great resource, and may be more than enough without taking water from te stream.
If you plan to capture 20,000 L in one tank I can help you plan it.
That tank would be about 4 M diameter.

Thanks John, good insight! I have to figure out where I can fit the rain tank, and how big it can maximally be in the space we have. The NE end of property where the house will be is sloped (house will be on stilts) so finding a flat zone may limit how big the tank can be.

We also have a few solid DRY months per year (May-Aug), which I guess 20,000L wont be able to supply a family and market garden throughout. So the well may be necessary as back up through those months.

Holly, 20,000L should carry any family over 3 months, do the sums.
How much water does a family use in you area, it will be documented somewhere?
There is something wrong with the planning if an area cannot be found to install a 4M diameter tank that will water the business and feed to family.
I mentioned the tank would be 4M diameter and a second tank can be installed if you need it.
So the house is planned to be away from the road? That means you will have land covered as a driveway.
There are better ways to lay out te property and fit all you need in.
Most places start with one tank and monitor how it performs. Remember you dont need a pump to fill it and may not need one to move the water.
Anything else will need pumps to collect it.