westernrvparkowner wrote:
WTP-GC wrote:
Lantley wrote:
WTP-GC wrote:
westernrvparkowner wrote:
Apparently you have no comprehension regarding septic systems. That 3" or 4" pipe leads to a holding tank and all the solids settle to the bottom and the liquids flow thru perforated 1 inch pipes into the drain fields. To determine how much area those perforated pipes must cover the engineer performs a percolation test. They then use a formula that takes the percolation performance and the amount of liquid anticipated to determine the size of the drain field. Far exceed that liquid amount and the liquid doesn't seep into the ground and instead forms pools of waste water on the surface. As I previously posted many parks have several septic systems and the systems tied to full hookup sites are designed to process that waste, not the waste of multiple dumps in a rapid succession.
One of the interesting parts of this thread is very common throughout the forum in general: people believe certain things to be universal in nature. And this comment above is extremely indicative of that mindset.
As a matter of fact, I've spent my entire career, over many years, designing, building, expanding and consulting with people about their sewer systems. Don't make the mistake believing that your onsite treatment system in Montana is equitable to every other campground out there (as your comment suggests). The description of your system is different that every other system I've been involved with, so...
If it makes you feel any better we have those same drain field systems in Maryland. MD is a long way from Montana somehow drain field technology made it this far.
The general concept behind a basic septic system is piping into it, holding tank (for septage processing) and piping out to a drain field. Beyond that, there are nearly endless configurations, pipe sizes, drain field design, etc. based on location, code, and other factors. I’ve been to South America where the also have similar septic system designs, but their drain field arrangement was remarkably different. The point is that septic systems may look the same at the most basic level, but they vary greatly. I’ve worked with folks who have septic systems at their multi-use facilities, and their systems had to be designed to accept the dumping flow of dishwashers and laundry facilities all at once, plus the normal bathroom loads.
As I mentioned in an earlier comment...if no rules against it...
You need to make up your mind. When I gave a description of a typical septic system you said you have consulted and built systems for decades and never have seen one like I described. Now you are describing systems you have built and they are EXACTLY the same as I laid out earlier. You are even saying that systems have to be designed differently depending upon the anticipated loads. The implication in your "multi-use" facility system is that if the system was designed only for normal bathroom loads, the addition of dishwashers and laundry facilities would overload the system.
That is exactly what I was pointing out in regards to a system designed for full hookup RV sites. They are designed for the loads generated by the RVs in those sites, not for the additional loads of multiple RVs dumping. The dump station in many parks has it's own set of tanks and drain fields designed to handle that load. It is a very common design for RV park waste systems.
To be more clear, when you said the following:
"liquids flow thru perforated 1 inch pipes into the drain fields"
That I have never seen. Admittedly, designs vary by location (as I already stated), but I've never ever seen 1" pipes going to the drain field. In all the systems I've been involved with, the tank outlet going to the drain field is 3" or larger. Sometimes its perforated and sometimes its a sock and sometimes its domes...and so on...
But again, the point I made from the beginning is that none of these systems are universal in design. I don't know how many times I have to say that, yet people simply don't get it.
A campground is...what exactly (in terms of it sewage treatment design)? Residential, commercial, industrial, mixed-use?????? Therein lies the problem. A FHU site should be designed for the sudden deluge of a 30-80 gallon black tank, simultaneous with a 30-80 gallon grey water tank...at the fastest rate it can be possible travel through a 3" flexible hose. I was not aware that ALL campers leave their grey water tank open all the time. What if 2 neighbors decided to dump their full tanks at exactly the same time. God-forbid that 3 or more neighbors do it at the same time. I've camped in groups before where this happens because we're all leaving at about the same time. That's where the entire argument falls apart. Also, all the FHU sites I can recall are no less than 4" pipe. How far is it to the septic tank (if not using public sewer)? 100'? 1000'? A 4" pipe can hold about 50 gallons of liquid every 100'. So generally speaking...a refuse to believe that a few people using a FHU site to dump instead of the dump station can create and problem or system overload. And in all the conjecture on here thus far...NOBODY has actually seen it become a problem in any way.
When you say this:
"That is exactly what I was pointing out in regards to a system designed for full hookup RV sites. They are designed for the loads generated by the RVs in those sites, not for the additional loads of multiple RVs dumping. The dump station in many parks has it's own set of tanks and drain fields designed to handle that load. It is a very common design for RV park waste systems."
Are you suggesting that each site has its own drain field? I know that's not what you mean, but it sure sounds like that. At a minimum, each loop or section of the parks should be tied in on the same sewer line. Maybe each loop or section has its own septic (if applicable), but if you have 30 RV's parked in a section, each should be connected to the same sewer line (underground) and the system had dang sure be able to handle the load of at least half of those dumping simultaneously.
