Cathy, you have a beautiful yard there and quite a talent with the camera, as well as gardening and landscaping, but I'm sure you already know that. I wish the pictures on your website would display larger, though, so I could see a bit more detail as to exactly how you're thinking about going about this two-pond system. First, your current "dry creek bed" looks great, and I see you have it surrounded by a variety of perennials which no-doubt benefit from the water that seeps through those rocks when it does act as a drainage area... As for contamination in your pond system, if you build your lower pond there, you'll likely have to remove all the rocks to start with, in order to keep your liner from being constantly punctured. You could try to do it without a liner, using something like Bentonite clay, or a compound such as gunnite, but those are both beyond my level of experience... Either way, if you build it where it DOES still get some runoff, yes, it will get "polluted," but not necessarily "contaminated." I have a two-pond system with a 55-foot stream between them, and unfortunately my lower pond sits where runoff sometimes overwhelms it when we have heavy downpours (I'm still working on redirecting that after three years -- we had gone MANY years without such heavy rains when I built it, and I had forgotten we got such rivers in our yard until I got to see my liner floating up from water going underneath it firsthand!)... The things you learn the HARD WAY, huh? :) Anyway, even when mine just gets runoff IN IT, and not under the liner, I end up with a brown, muddy-looking pond for a day or two, but it clears -- BUT I don't use any chemicals in my lawn and nothing but some liquid fertilizer on my flower beds... If you have pesticides, herbicides, roof shingles that are leaching chemicals and whatnot UPstream of your drainage, those could all be concerns if you put fish and/or plants in your ponds. My biggest question, however, is exactly where and HOW you plan to implement the larger pond ABOVE the dry creek bed, as from the pictures I could see, your yard appears fairly level on both sides of that dry creek bed, and of course you'd need a few feet of incline for the "upper pond" to be above the "lower pond," unless, perhaps, you're thinking of putting something on the deck that cute cocker spaniel was sitting on. That's a possibility... It would have to be more of a tub-pond, like maybe a converted hot-tub, or possibly a preformed pond fitted into a structure you built, but it can be done IF the deck is sturdy enough to hold the weight (bear in mind that water weighs about 8 pounds per gallon and there's 7.5 gallons per cubic foot, so you can have a ton of water pretty quickly... roughly 250 gallons equals a ton). But if you have the time, the money, the patience and are willing to do your homework ahead of time AND/OR make sure you hire people to do the work who REALLY KNOW WHAT THEY'RE DOING (there are PLENTY of folks doing this who DON'T), I think you can do pretty much anything you want to. Best of luck to you! Jeff

Looks great. I need to do one as well to minimize runoff from our pipes into the neighbors yard. The space is narrow and has a lot of tree/bush roots. Most recs are to make it at least 2 feet wide. Will it still work if its only a foot or 6 inches wide?

Thank-you people! We now have a fairly long dry creek which needs to handle a high volume of water. It has two levels - water comes in from the top and is "visual" and then directly under this is a hidden french drain - they all drain into a dry pond which will be filled with moisture loving native plants to clean the ground water - then it all goes back into a pipe and down the way. There are also funky tributaries to our dry creek to handle all the water coming down the bank, a few more areas need to be incorporated. It was made by the contractors and we just used rip rap but I will also add in my concrete "chunks" and the few nice found rocks the contractors dug up while grading. Eduarda, thanks for that article! It's perfect. Essentially I want mine to look like a cross between Cameron's beautiful dry creek and the Fine Gardening dry creek. Cameron, I will need to get some ideas from you about the native grasses you planted in here. Luckily I will have the ability, if necessary to "reverse" the flow of water from stored water back into the dry creek to keep everything moist. A pump and an underground water line that runs back up to the "front" of the stream will do the trick. So far our "project" is shaping up very well. A few more things need to happen before the patios go in - more retaining walls and drainage. I've got a LOT of planting to do these next few years. I have a feeling winter sowing will be my best friend!

Back to the real problem children. It is now accepted here in Australia and I am sure in some land management circles in NZ, that piping or concreting natural waterways creates significant environmental problems. This is now recognised in most developed countries. By concreting a waterway, the velocity and volume of the water is increased. I wo'nt go into the figures, but as communities expand, there is a incremental increase in the surface run-off of water. Imagine the inner city area of say Auckland. Most of the land area is now covered with buildings, roads, etc. so that nearly all the rainwater just runs off into the drainage system. The more the suburban fringe expands and the inner area gets built on, the larger the volume of water, that is prevented from soaking into the soil or just meandering through a catchment. But it all starts upstream, when the first house gets built and then the roads and so on, etc. etc. Back to the creek. When increased runoff hits a nice smooth concrete surface it gets faster and compounds to such an extent, that severe erosion and flooding now occurs down steam. This can be disastrous. In my landscaping lectures I recall seeing lots of photos of erosion and slippage etc. in New Zealand. Flooding is now tragically common in the lower suburban areas of the Sydney basin and I am told in parts of Wellington. It may well occur in other communities of New Zealand as well. As a result there are severe requirements on housing estates etc. to inhibit water runoff. Swales, detention basins(dams), wetlands to take out nutrients, etc.,are now mandatory. You will find this the same in America and Europe as well. For example, those big open concrete drains we see beside freeways that once were creeks are now being ripped up. Landscaping companies are being contracted to reinstall a sort of creekline that has curves etc to slow the water. Millions are being spent here, to recreate a sort of creekline with obstructions like rocks and even the broken concrete from the old open drain is being used. Vegetation is being reintroduced as it also slows down the water as well as helping to deal with erosion, take out nutrients, encourage habitat etc. What appear to be large parklands or football fields, are now detention basins designed to hold water run-off in severe downpours. Regarding your problem with the eels. This is an area where I know very little about. But I would suggest introducing more rocks of varying size so the holes are smaller between them. Is there a way to live with the eels and yet prevent them damaging the creekline. My bet is, if you put down a pipe you will add to a problem further down stream. A natural stream sounds like a great thing to have. Consider the cost piping the creekline and spend that budget on planting and improving the 'natural' look. Might I dare suggest you talk to a sandal 'wearer.' One of them might just be of help regarding the eels.