Septic System Design in San Francisco, CA
First and foremost, hire a good septic designer to do the necessary tests and drainfield design, BEFORE you design the house!!! Go out with them and tell them where you would like to situate the house, but let them give their input. Sometimes just moving the house a few feet in one direction will make the difference between a regular, gravity fed system and a more expensive pump system.
I had some friends that were going to build and I tried advising them on this, but wouldn't listen. The irony is, if they would have listened and moved the house about 10 feet to the west, they could have gone with a gravity fed system for about $3,500. As it turned out, they spent more than $8,000 because they put the house right where the drainfield should have gone.
Also, if they say you cannot go with a regular septic system design, ask them about ALL the different types of systems you may be able to go with and the advantages/disadvantages of each type. If they are pushing you toward one type of septic system design in San Francisco, CA it may be because that is the only type of system they do. You may want to take your copy of the site/soil conditions (make sure to get a copy) and call/visit a few other contractors to get their opinion.
When you buy property and are going to put in a septic system, there are safeguards that are supposed to protect you. The way the process is supposed to work is, you, as the property owner, hire a septic designer to assess the site and design a system that will meet the needs of the home and will work with the existing site/soil conditions. They then present this plan to the local agency in charge of septic systems, usually the health or zoning office. They approve or disapprove the plan. Then a septic installer installs the system according to that plan. Then the building inspector comes to the site and inspects the system to make sure the system was installed properly (according to the plan).
This is the way it is supposed to work in theory...but it doesn't always go according to plan. The skill level of designers, installers and inspectors varies greatly from state to state. Some states, such as Massachusetts, are very progressive. They require the contractors and inspectors to be well trained and certified if they are going to be dealing with septic systems. They are also open to new technologies available to solve problem sites.
However there are areas where the contractors and the government inspectors are way behind the times. In some regions anyone that has a dump truck and a backhoe can dig a septic system. septic system design in San Francisco, CA. Some of the agencies will still allow systems to be installed that will be illegal in a few years when the local regulations catch up and are enacted. An example is the use of deep systems like cesspools and drywells. These systems have outlawed in most areas of the country but there are a few that still allow them today. What this means is, you can have a cesspool put in now, but in a few years the codes will change and you will have to put in a new system- at your own expense, of course.
The end result is that some of the systems going in are failures waiting to happen. This is why you as the homeowner must take an active role in the septic system design in San Francisco, CA process.
When you know where you want to buy, talk to neighbors that have built in the area in the last few years and ask them what kind of system they installed (don't rely on what someone had a system installed 20 years ago- the codes have probably changed and there is a good chance that their type of system is no longer acceptable. Your local Board of Health can also be a valuable resource. They can not tell you who not to use because that is preventing someone from making a living, but they will often point out the better ones because they know a bad contractor putting in bad systems will make their job tougher.
You may also want to hire a contractor that can also do your other dirt work (the basement, footings, landscaping, etc). If you are using several different contractors the contractor that is digging your footings will often drive over the area where the septic system is supposed to go and damage it. If you have one doing it all they will protect the area when they are working.