Albeit very humorous it is very true and a very important issue.
As a general contractor distressed property rehab specialist for the past 3 decades we've done hundreds of drainage projects all over the SoCal area. Additionally I've been a "cross lot drainage "Expert Witness" on dozens of drainage issues and am currently involved with a multi million dollar class action litigation on this very subject.
I can tell you first hand that water in, around or under a dwelling is trouble and a one way ticket to a very costly law suit let alone repair bill. By law your neighbor is not allowed to let water drain from his lot to any adjoining private or public property.
Drainage be it surface runoff or subsurface percolation should always be caught and diverted to a storm drain system; usually the street gutter, whereby it will flow to the major storm drain system. This sometimes if not always requires a two fold approach.
The first is to install a French drain system around the entire perimeter of the structure. A French drain is a subterrainean drain comprised of trenching, installing a gravel envelope around a filter cloth thereby allowing water to filter through it and into a perforated drain pipe installed on at least a 1% slope, aka fall line) which leads to the storm drain system or a sump well and pump system.
The second type of drain (usually run in the same trench as the French drain if not tied into it) is a surface drain system whereby a soils and/or civil engineer locate the low spots and install a catch basin with drain pipe leading to the trench and escorting the water to the storm drain system or to the sump well where it is pumped into the main storm drain system which is usually the street gutter.
I must also give Cory a thumbs up for her astute observation regarding potential structural ramifications to the home. It's not uncommon, especially in San Diego's predominantly very expansive clay soil environment to realize mild to severe movement as the clay expands and contracts over the years.
This perpetual motion causes a structure to settle and shift resulting in cracked founations, seepage to the interior of the structure if it's a slab on grade or into the crawl space where it sits and collects for years on end resulting in mold issues as was addressed by Frank.
All in all it is definitely not normal nor is it acceptable and should be addressed and corrected ASAP. Given home is in San Diego and we are still actively involved in this trade skill I would be more than happy to have my son, Chad Arendsen, principal of "Chad of All Trades" http://www.chadofalltrades.com give you an assessment and cost to repair this problem for either your seller or buyer.
However, be advised that a properly designed and installed drain system is still not a cure all to the problem. A drainage issue is a drainage issue because water inherently seeks its lowest level and unfortunately that can end up at the doorstep of someone's home.
The only remedy is to catch and divert the water but it's still going to be an ongoing issue which will have to be periodically monitored and maintained as the drain pipe can clog up with soil and roots and the sump pump system, if needed, needs to be periodically inspected and maintained.
Should you have any other questions or concerns please feel free to contact me at 760 815-6977, firstname.lastname@example.org or log onto our website at http://email@example.com. Good luck.
I think the only time it is appropriate to have water running under your home is when you live on a Yacht!
From what you describe it sounds like a French drain AROUND the perimeter of the home connected to the sump pump would be a better call. I would definitely get the opinion of a local drainage specialist and then remedy the issue to mitigate post transactional exposure.
"The seller, who is originally from the Midwest (where basements and sump pumps are common, seems to think the situation isn't unusual..."
It really doesnâ€™t matter what the Seller thinks, we're not in the Midwest anymore; we're in the litigious State of California. Remedy the issue and then place it on market with full confidence thereâ€™s nothing that will come back to bite the parties involved.
Even if it's not a problem and is normal, wouldn't your seller want to know for sure? Sol in some parts of San Diego can be poor to begin with. Foundations, framing, windows ... all expensive to fix. You could get an an inspector with extra foundation and soil training to offer an opinion. It could save the seller from a potential, and really costly I'd think, lawsuit from the buyer if something happens. And, your seller will have to disclose it, so better to have been proactive and put the buyer's mind at rest with the inspection report. If you have buyers cancel because of it, the listing will sit on the market longer and down goes the price. Just my opinion. Good luck with this!
A rain gutter sysem around the roof line is as natural as grandma and apple pie. However, do be careful tying it into another drainage system. It's important to make sure that the other drain systems main drain pipe is larger than all the other drain pipe leading to it.
Example if you're running a typical 3 inch perforated French drain pipe and a 3 inch tightline (solid pipe) to transport the surface drainage and still another 2x3 inch down spout all into one main drain line be sure to make that main drain line at least six inches in diameter. Faliure to do this will result in a back up of all the drainlines which will totally defeat the purpose and will exacerbate your problem.
If the property has enough fall to gravity flow the water to the street gutter you would then need to install a manifold that would resevoir the water and transfer it to a series ot smaller (generally 2 to 3 three inch pipe) tight line in order to be able to core cut through the curb.
If the lot does not have enough fall to the street gutter then you will need to install a sump well and pump system at which time whence you could then pump the water to the street gutter with a 2 inch tight line. Should you need a sump system it will also be necessary to install a dedicated 110v outdoor reciptical. In many if not most cases you would also need to consider a back up system in the event of a primary pump failure. Hope this helps
In any event from the sound of things you may want to consider retaining a soils engineer in order to determine the depth of the saturation in order to deal with the percolation issue which is the ground water that is forced up through hydrostatic pressure. This is just as important as catching and diverting the surface runoff. Good luck.
760 815-6977 firstname.lastname@example.org
The other fix I have suggested is a rain gutter system for his roof which can be plumbed directly into a drainage system as another method to keep water away from the house. I will be looking to see if the neighbor has gutters and if not, see if we can get them to install them as well. He is having another agent (vanity name in the area who claims to be the local expert) come over tomorrow (actually at my suggestion). Many agents look past these issues to get the listing and then deal with them as they are brought forward by buyers. He is smart and will stick with me, but it will be interesting to hear what she has to say.
Thanks again everybody!
I agree with your worry that to maintain the status quo could lead to a lawsuit down the road. I would push for a drainage system to be installed, any stagnant or pooling water can cause an area within a home to have a micro-climate that may foster the growth of mold that could further damage the house or cause the residence to become sick. I personally would not feel comfortable with that as even a possibility.
Get some quotes/shop around, there are companies that specialize in basement/crawlspace drainage and they may be able to answer some of your question about whether or not leaving it is kosher. The water may just need to be redirected. Good luck! http://www.permadrywaterproofing.com/