Salinity

I hope someone here knows a bit about soil and water analysis.

In March 2013, I had the soil tested in my yard. I had an area about 15 feet wide that
was had such bad soil NOTHING would grow - not even a weed.

In 2003, we had 22 inches of rain (average here is 12 inches). The area was very boggy.
We dug it up thinking it was a broken water pipe. It wasn't. Ground water is 6 feet below
the ground. Salt deposits were all over the grass (well dead grass because of salt)

While the "pit of despair" was open, I sent in a sample of soil.

The report came back with a letter.

The letter says "The soil is PH neutral with high fertility except for modest nitrogen.
However it is not suitable for sustaining the growth of most plants, especially crops.
The salinity is excessively high at 8.45 millimho/cm. Normally the salinity should be
less than about 3 for many plant and lower for salt-sensive plants. Soluble sodium,
chloride and calcium are high. Lead is low. Cobalt is moderate"

Ironically we had 2 inches of rain last year. I'm considering uncovering the pit again and
using the water for the hill behind it (80x60 feet) for my food forest. I'm wondering if I
used half of this water and have of the city water how my nitrogen fixing and fruit trees
would be. (I'd cut it with rainwater if I had any!)

Is it too salty? It is also very high in sulfur.

Would love your thoughts!

Thanks
Sheri

I can't think of any reason to do this. Why do you want to do it ?

Because we are in the middle of a drought.

Yet, I have as much water as I can possibly want 6 feet down - of course the problem is that it is salty

I'm trying to do as much rainwater harvesting as I can - just about to put in gutters and then I can direct the rain.
I'm going to put in a greywater system soon so I can use the laundry water.

You're question confuses me a bit - why would I not want to?

Thanks

Soil salinity is not something I'm likely to come across in NZ. Whew!
In this fao document they say 4.5-9 millimhos/cm is 'slightly saline', but I think even 'slightly' is too much for many plants.
I think this is an important conversation, and hopefully drylanders will comment
More drought combined with more saline groundwater is going to be a reality for more and more people.

Even slightly salty, for irrigation water can be too much. As the water evaporates, salt is left behind. The soil becomes more saline with each watering. It can only work in spots that occasionally get massive amounts of good quality water, which is used to flush the salt from the soil. This type of surplus is not usually the case, in areas with salt problems.

It's better to harvest rain water and gather other surface water.

Most efforts here for reducing salinity is to grow salt tolerant species to lower the salty water and keep it off the surface. Putting it on the surface is just asking for trouble.

If using saline water to irrigate non-saline areas is imprudent -- as I understand it to be -- how about this? Try to find a salt-tolerant species that produces.copious foilage, then use that foilage as a green mulch for the areas you want to irrigate. This will contribute a quantum of moisture, but also reduce evaporation and make the irrigation water (from rain or whatever) go further. (This assumes there are salt-tolerant plants that make non-saline foilage, which I believe but have not researched.)

In other words, leave your salty groundwater where it is, but try to make it a resource.