Back on part 2, Amanda had commented that having some sense of time scale was helpful, so I thought I'd reconstruct a small timeline to help others set their expectations realistically.
The main point to remember is that I started with a sinkhole, most of the 'digging' work was what the land had already provided. It gathered a little water naturally, but despite our clay soil, it still had a fairly quick infiltration rate, not enough to be workable as a pond without a liner.
For a real pond project, others without a natural feature like this would likely bring in heavy equipment or a group of friends to do a LOT of hard digging. No matter what your soil type, this can be really rough work because most functional ponds are at minimum several feet deep in their deep areas.
You'll also want shallower areas, ideally some about a foot deep to place plant pots on and some areas just several inches deep, both for plants and for animals that rely on such areas for key habitat.
I have some plants in plastic 'net' pots, others in mesh 'pots' and still others planted directly into soil I added to the bog area. I filtered out most of the topsoil and used a clay leaf mould mix to keep down clouding and help plants stay put. About halfway through the project I realized I was going to want plants in the deep end of the pond as well, so I added a floating planter, again with the clay leaf mould soil mix.
May 10th- This is what I started with, a big natural sink hole, now cleared of sticks and most rocks then I began adding well rotted leaf mould beneath as an underlayer-
These are pretty much the "before' pictures. It's hard to parse, but you can begin to make out the 'slope' along the lefthand side in sunlight-
There are a lot of 'imperfect' compromises in this project, use of plastics, etc, but there are also some bits of reuse. These carpets didn't go to the landfill, they form an underlayer cushioning the main liner-
20'x20' (slightly over 6m by 6m) HDPE primary liner with the close edge folded under. The life expectancy on the liner (given solar radiation and winter freeze cycles) is typical 20-50 years in situ, which is likely my lifetime here. If someone wants to rebuild it more professionally later, they're welcome to. Getting the liner down into all the crevices meant some sock footed getting down into the hole and carefully smoothing the thick liner into place.
May 14th- I timed our initial construction just before two 3" (7.6cm) to 4" (10.1cm) huge rainstorms. This area is mostly a gentle downslope headed towards a stream in the woods directly behind it, but it also gathers water from the yard around the house above it. The initial rainfall gathering didn't quite fill it, but certainly did the bulk of the work. You can see it begin to take shape and where the shallower 'shelves' are. Off the lefthand side of this picture, water also gathered uphill at that front left corner, making it clear where another small filtration basin could be added later.
May 15th- we sighted our first frog resident.
May 17th- I doodled up a plant plan that included the upper basin, almost all of these plants are in the pond as of three months in. They are not all natives, but everything in here serves a purpose.
May 22- a first batch of pond plants arrived mail order.
Throughout this period, I was doing a lot of pond research, and looking for native plants locally. I found this online free guidebook useful.
May15- our first pump/filter attempt. I had initially wanted to utilize a solar pump, but found it both too low flow and without enough sunlight hours to really do the job, so I eventually moved it to a much smaller container pond.
Pumps need to have a mesh barrier to help keep debris out. So I gave it a cube structure inside a mesh bag. The top hasn't been closed in this picture.
We got more rain and I dug out the upper basin a bit, it's in the front left corner.
May 17th- we topped it off with spring water and can now fully understand where the edges are when full.
May 20th- First plants are potted up in mesh sacks with clay soil mix and gravel on top, added to the shallows. Just a couple inches of water to get them started.
I'm starting to find animal pawprints on the edges of the liner, raccoons, squirrels, etc.
June 5th- I've started adding rocks around the edges and the white stones at the righthand side wildlife exit "beach" is in. The pond is behind benches in this, that's temporary. But you can see how it relates to the greenhouse and herb spiral as it's at the edge of the woods.
I've dug out and re-added clay soil mix to the shallow "bog" along with some native sedges, floater plants are in, and I've added a couple logs along with the rocks at the edges.
June 12- I've given up on the solar pump, moved on to a higher capacity pump. We've run electricity from the greenhouse across to the pond and I've added a 'waterfall filtration' box up top.
June 13th- We go to an aquatic plants workshop and bring home more plants and some intentionally added tadpoles.
June 20- larger frogs are clearly living in it. The floating planter is added and the rest of the rocks now ring the pond. I've started adding mulch to cover the liner edge. The upper basin (lower left) has white pebbles, irises and the bare waterfall box. The sit spot bench has been added.
June 27- the bareroot water lilies are finally coming up. The horsetail is growing.
July 2- lots of late evening firefly watching down by the pond and frog song.
July 3- a pump failure. Began clearing the outflow trench now that I can see where overflow is coming out of the pond in heavy rains. Adding lots more mulch now.
Added the rock cave around the waterfall filtration basin-
July 9- Replacement, 'we're serious now' pump.
July 25- We (finally) added a garden shed across from the herb spiral, the pond is quietly tucked away sort of hidden behind it from some angles, making it a quiet spot.
July 30th- added the bullfrog spitter to help oxygenate and add more water sound.
Aug 10th- Current state, all mulched in, rock ring has better placement now, and the plants are growing in.
Could it all be accomplished much more quickly? Of course.
But observation, seeing how the water rested, where outflow was, what opportunities for things like a filtration basin were, how best to use the land itself to help oxygenate, and reusing rock from a previous greenhouse floor and nearby logs all came by 'living with it' for a bit and seeing how it all starts to work together.
The new shed has a metal roof for rainwater collection, a gutter system, and will get a rain barrel that can be used to top off the nearby pond as necessary. These are different components of my design working together. The excess floater plants will go to the nearby compost in time, which in turn will feed my fenced in raised beds potager.
The outflow from the pond and excess from the shed will water a native plant walk down towards the stream.