Guidance and tools to calculate nutrient budget for developments within Special Areas for Conservation (SAC’s) river catchments.
Guidance
Nutrient budget calculator: guidance , file type: PDF, file size: 1 MB PDF 1 MB If you need a more accessible version of this document please email [url=mailto:digital@gov.wales?subject=Request%20for%20%27Nutrient%20budget%20calculator%3A%20guidance%27%20in%20an%20alternative%20format&body=Details%20of%20document%20required%3A%0A%0A%20%20Title%3A%20Nutrient%20budget%20calculator%0A%20%20Page%3A%20https%3A//www.gov.wales/nutrient-budget-calculato ... 0prefer%3F]digital@gov.wales[/url]. Please tell us the format you need. If you use assistive technology please tell us what this is.
Nutrient budget calculator , file type: XLSX, file size: 10 MB XLSX 10 MB If you need a more accessible version of this document please email [url=mailto:digital@gov.wales?subject=Request%20for%20%27Nutrient%20budget%20calculator%27%20in%20an%20alternative%20format&body=Details%20of%20document%20required%3A%0A%0A%20%20Title%3A%20Nutrient%20budget%20calculator%0A%20%20Page%3A%20https%3A//www.gov.wales/nutrient-budget-calculato ... 0prefer%3F]digital@gov.wales[/url]. Please tell us the format you need. If you use assistive technology please tell us what this is.
Nutrient budget calculator: frequently asked questions , file type: PDF, file size: 372 KB PDF 372 KB If you need a more accessible version of this document please email [url=mailto:digital@gov.wales?subject=Request%20for%20%27Nutrient%20budget%20calculator%3A%20%20frequently%20asked%20questions%20%27%20in%20an%20alternative%20format&body=Details%20of%20document%20required%3A%0A%0A%20%20Title%3A%20Nutrient%20budget%20calculator%0A%20%20Page%3A%20https%3A//www.gov.wales/nutrient-budget-calculato ... 0prefer%3F]digital@gov.wales[/url]. Please tell us the format you need. If you use assistive technology please tell us what this is. 9 February 2026
The Nutrient Budget Calculator for Wales is used to calculate phosphorus and nitrogen mitigation requirements for development within the catchment for rivers that are SACs and some marine SACs.
There are nine SAC rivers in Wales. Nutrient budgets for development need to be calculated in seven of these river catchments which fail nutrient water quality targets. Nutrient budgets are also required within freshwater catchments of three failing marine waterbodies.
Nutrient budgets are required in these catchments:
- River Gwyrfai and Llyn Cwellyn
- River Teifi
- River Tywi
- River Cleddau and areas around inner Milford Haven
- River Dee & Bala Lake
- River Usk
- River Wye
- River Lougher
- River Eden, Cors Goch Trawsfynydd
- Meirionnydd Oakwoods and Bat Sites (the Afon Glaslyn)
You can find further guidance on completing the calculator in this instructional video.
For any queries or issues with the calculator please email: [url=mailto:decisionsbranch@gov.wales]decisionsbranch@gov.wales[/url]
Wastewater Treatment Works permit figures updated on 7 July 2025.
Source: https://www.gov.wales/written-statement ... ase+2+bans
