soil investigation

[eng2424]

For a preliminary design for a subdivision, into how much detail do you look at soils for you layout/concept plan?

When looking at soil surveys and run across soil that say sever of moderate sever for building pads or septic systems, is this land/soil buildible still or is this land unusable then?

Would you still layout lots on these areas?

What would be the next step if soil surveys indicate poor soil? Go ahead with concept plan including layouts on poor soils? Concpet plan discluding these areas? Soil borings before a concept plan is even started?

 

[eric1037]

Personally, I believe that you owe it to your client to point out that there may be poor soils. This is especially true if the client has not purchased the property yet. I believe it would be unprofessional to go ahead with work that you know (or suspect) will be useless.

If the client has already purchased the property and is committed to the project, then it would be advisable to do some preliminary geotechnical evaluation, including soil borings and/or test pits.

I am not sure what the terminology "sever of moderate sever" means. Is this a typo or what it actually says?

I would contact a local geotechnical engineer and get their input on it. They may have knowledge of the soil conditions in that area.

 

[sam74]

Do you plan on using septic systems? If so that could be a big/costly issue and the need for immediate soil surveys to determine areas that would allow a septic system and of what size they would need to be could drive your design (lot size and location). Either way I would think that you would make your client aware of the situation and await his decision on how he/she wants you to procede. If he chooses to ignore your findings and wants to procede with maximizing site layout I would document your previous conversation and ask that he/she signs of on/acknowledges the conversation and the direction that is being taken. Building pad issues could become more expensive than normal according to what methods are needed but shouldn't take up more space horizontally than any normal method unlike the septic issue.

 

[Slugger926]

In the subdivision I am in, we have really poor soils with bedrock as shallow as 1 foot. This cost money in laying pipes and escavation work. Also the builders had to spend more money to build the houses, and bring in top soil for the yards. In the end, the house buyers paid for the extra costs.