Advice on large garden renovation

[SolRobinson]

Hello, due to unforseen circumstances, I have 3 months to renovate our garden in order to be able to facilitate a garden room workspace.

I have no landscaping experience, but am an avid diyer and will try anything. I'm intending to hire a digger & dumper, scrape everything off of the top & then dig out any areas I intend to pave or build on.

Our main problem is drainage. At the very back of our garden is a sink hole (circled in red) the sink hole is aroud 4/5 inches deep and has formed due to water sitting in that area. I'm hoping to combat that by installing land drains along the edges of the garden, starting from the back and running to the front, up the the retaining wall, where I will install aco drains to take the water away into the combined sewer system. Although a friend had told me that they would recommend installing a soak away just at the top of our steps, but as this is where we will be having a garden path, I assumed this would cause us issues?

Along with the drainage, I have a small pond (circled in blue) to tackle, it has a liner, so I'm hoping this won't be a problem for me and I should be able to dig out the area with the mini-digger, removing the liner and filling the whole?

I also need a 3rd trench digging in the garden for utilities for the outbuilding. I want to ensure this is as maintainable as possible, so plan to run all cables through pipe, to allow for more/replacing cables in future, and will run a MDPE water line alongside the pipe. The orange line indicates the path for the utilities, this line runs directly down the side of our house, towards the garage which houses our consumer unit. My question is, how do you go about getting the pipe through/under/over the retaining wall? It is a case of digging deep enough and coreing through the walls (assumed) concrete foundation?

Finally, I plan to build the outbuilding out of timber, we're undecided whether to self-build or buy prebuilt, however, either way, the foundation plan is to be block piers. This saves us having to barrow concrete back and forth as it is quite far from the front of the house to the back. My concern is that the outbuilding is going to built where the sink hole currently is. I'm concered that if the land drains don't fix the drainage issue, the blocks could subside and cause issues with the outbuilding.

Any input on my plans here is much appreciated!

https://imgur.com/FLSFpY1

 

[blup]

Hello, due to unforseen circumstances, I have 3 months to renovate our garden in order to be able to facilitate a garden room workspace.

Does this mean get the whole thing built?

I have no landscaping experience, but am an avid diyer and will try anything. I'm intending to hire a digger & dumper, scrape everything off of the top & then dig out any areas I intend to pave or build on.

Give yourself time to practice, trenching is manageable, scraping is a much finer art. Rent a mini dumper to shift anything surplus or across the site. Muckawayfor anything going off site.

Our main problem is drainage. At the very back of our garden is a sink hole (circled in red) the sink hole is aroud 4/5 inches deep and has formed due to water sitting in that area.

Dig it out to identify how to deal with it.

I'm hoping to combat that by installing land drains along the edges of the garden, starting from the back and running to the front, up the the retaining wall, where I will install aco drains to take the water away into the combined sewer system. Although a friend had told me that they would recommend installing a soak away just at the top of our steps, but as this is where we will be having a garden path, I assumed this would cause us issues?

Soakaway, you cannot generally drain into a combined sewer, and presumably won’t need that service unless you are putting in a toilet. All to be approved by BC

Along with the drainage, I have a small pond (circled in blue) to tackle, it has a liner, so I'm hoping this won't be a problem for me and I should be able to dig out the area with the mini-digger, removing the liner and filling the whole?

Yes

I also need a 3rd trench digging in the garden for utilities for the outbuilding. I want to ensure this is as maintainable as possible, so plan to run all cables through pipe, to allow for more/replacing cables in future, and will run a MDPE water line alongside the pipe. The orange line indicates the path for the utilities, this line runs directly down the side of our house, towards the garage which houses our consumer unit. My question is, how do you go about getting the pipe through/under/over the retaining wall? It is a case of digging deep enough and coreing through the walls (assumed) concrete foundation?

Pneumatic drill, or dig out as footing likely to be nominal.

Finally, I plan to build the outbuilding out of timber, we're undecided whether to self-build or buy prebuilt, however, either way, the foundation plan is to be block piers. This saves us having to barrow concrete back and forth as it is quite far from the front of the house to the back. My concern is that the outbuilding is going to built where the sink hole currently is. I'm concered that if the land drains don't fix the drainage issue, the blocks could subside and cause issues with the outbuilding.

You will save a shed load doing the ground work yourself, spend it on a pre built garden building. Quality wood is expensive and the saving may not be as great of look as good if you DIY it

Any input on my plans here is much appreciated!

https://imgur.com/FLSFpY1