A curious plan and comparison
In researching Lodge Park, with a bit of detective work, I came across a document that has never been publicly encountered before – it’s part of the Conservation Management Plan for Lodge park, written over 10 years ago. It's hosted on a webpage by the Cotswold National Landscape. It's extremely detailed and highly professional - an admirable document.
Here it is at this link. Plan 2, Restoration, Replanting and Management Master Plan. Client: the National Trust. Author: Christopher Gallagher, Historic Landscape Consultant. January 2016. A summary sheet from the Lodge Park Conservation and Management Action Plan. The link was live on 3 August 2026. It's not my document, and I therefore shouldn't host the document here, albeit it can be downloaded. You can see it at the link above.
Read what it says about the water in the valley bottom.
Re-establish the early formal canal as an open water feature, within its historic boundaries.
Reinstate the two smaller ponds shown here on the c.1820's Survey plan and the 2” Ordnance Survey Drawing (1815), with their associated features such as dams and connecting watercourses, as visible in the extant archaeology of the site.
Here is the 1820 estate plan showing the lakes in Lodge Park:

The Lodge Park estate plan of about 1820. The lower of the waters the CMP plan calls ponds, shown at its full extent, about 350 yards long. Eighteenth-century estate usage called such water "ponds" whatever its scale: Sir John Dutton’s own accounts of 1739 and 1740 record work on the lower pond including driving piles for the dam.
Compare to the situation in the valley bottom in Sherborne where we await release by the NT of the CMP written by the same author – lakes of a similar vintage or older. I won't bore you again, with the fairly strong evidence we have that the lakes in Sherborne date from about 1739/1740 (The lower 'Narrow-water") and older (The Broadwater).
I will leave you to compare the two situations, and to draw your own conclusions. I suppose there is no obligation for the National Trust to accept the recommendations of a CMP. If they intend to restore or re-instate the lakes in Lodge Park, they certainly haven't done that yet, although they have undertaken other significant parts of the CMP at a cost of hundreds of thousands of pounds. Maybe it's too costly and that wouldn't surprise me. But it is clear that the CMP view is that the restoration or even reinstatement of all of the bodies of water in Lodge Park are important, whatever their date. Remember, Lodge Park is open for just a few weekends of every year. Here in Sherborne, we live in the landscape, looking at what were once lakes every day. It will be interesting to compare this Lodge Park CMP with the Sherborne Park CMP if we ever get to see it.