Opens NutrientMonkey. Pick Derwent & Bassenthwaite from the catchment list and the phosphorus toggle locks to match.
Stuck behind a Derwent & Bassenthwaite nutrient condition?
The River Derwent and Bassenthwaite Lake in the Lake District form a phosphorus catchment where schemes may need to show phosphorus neutrality.
If your site drains to River Derwent & Bassenthwaite Lake SAC, the planning authority can't grant permission until you've shown the scheme is nutrient neutral — that it won't add phosphorus to a catchment that's already overloaded. NutrientMonkey gets you the number: build the assessment on screen, watch your budget in kg/year update as you go, and export the planning-ready report when it's right.
Which nutrient applies here
Bassenthwaite Lake is assessed for phosphorus, which fuels the algal growth that has degraded this protected lake. That matters, because the methodology and the credits differ by nutrient — and neighbouring catchments often differ. NutrientMonkey flags the Derwent & Bassenthwaite catchment for phosphorus and locks the tool to match, so the assessment is right from the start.
Credits in the Derwent & Bassenthwaite catchment
The Cumbria Nutrient Neutrality Partnership runs an official phosphorus credit scheme covering the Derwent & Bassenthwaite catchment. The scheme is live and applications are open (one credit = 1 kg P/year, sold in 0.01 kg increments). See cumbrianutrientneutrality.co.uk.
Published scheme prices (reviewed annually, excl. VAT): £10,000 per kg phosphorus/year for a temporary credit (where a wastewater treatment works upgrade is due before 2030) and £28,000 per kg phosphorus/year for a permanent credit.
Credit availability varies by sub-catchment: Derwent is currently limited and Marron is unavailable, so check supply for your site before relying on the scheme.
From 1 May 2026 the Cumbria partnership requires LPA-specific occupancy rates here instead of NE’s 2.4 default: 2.2 people/dwelling for Lake District National Park Authority sites and 1.5 for Cumberland Council sites.
One credit is 1 kg of phosphorus/year. The number you need is your governing budget — the greater of the pre- and post-2030 figures, floored at zero; where a 2030 permit change applies you can instead split into cheaper temporary credits (valid to 1 April 2030) plus permanent. NutrientMonkey shows these live so you can gauge how much mitigation you'll need before you commit. Prices and sub-catchment availability change — always confirm the current position with the provider.
How the Derwent & Bassenthwaite calculator works
- Pick Derwent & Bassenthwaite from the catchment list — it's pre-flagged for phosphorus.
- Enter the dwellings & waste water — occupancy, water use (125 or 110 l/p/d plus NE's allowance) and the drainage route (septic, package plant or mains permit).
- Add land use & SuDS — current vs future land cover and any sustainable drainage, with editable export coefficients for the Cumbria catchment values.
- Export when ready — a branded, planning-ready PDF with the budget in kg/year and every input documented.
Honest about what it is
This is a nutrient-methodology assessment built to support your Derwent & Bassenthwaite planning application — fast, clear and ready to discuss with your case officer. The official Natural England catchment calculator remains the statutory tool, and your figures should reproduce in it; the report states this plainly. Want it handled end to end? That's what we're here for.
Frequently asked questions
Which nutrient applies in the River Derwent & Bassenthwaite Lake SAC catchment?
Bassenthwaite Lake is assessed for phosphorus, which fuels the algal growth that has degraded this protected lake. A compliant scheme has to be neutral for phosphorus. NutrientMonkey locks the nutrient toggle to match the Derwent & Bassenthwaite catchment automatically, so you can't pick the wrong one.
Is the Derwent & Bassenthwaite calculator free to use?
Yes — selecting the catchment, entering your dwellings and watching the budget update in kg/year is completely free. You only pay £79 +VAT (£94.80 inc VAT) to export the planning-ready PDF report.
How is the Derwent & Bassenthwaite nutrient budget worked out?
It follows Natural England's published nutrient-budget methodology — waste water, current and future land use, SuDS, then the final budget with the ×1.2 (20%) precautionary buffer. For new homes the waste-water term does most of the work and is computed exactly.
Is this the official Natural England calculator?
No — it's a fast, planning-support assessment that implements NE's methodology, and the report says so. The official NE catchment calculator remains the statutory tool, and your figures should reproduce in it.
In a different catchment?
NutrientMonkey covers every Natural England catchment.
Also in the Cumbria area:
Or jump to another part of the country:
- Poole Harbour N
- Solent N
- Tees (Teesmouth) N
- Lindisfarne N
- Stodmarsh N & P
- The Broads N & P
- River Wensum N & P
- Chesil & the Fleet N & P
- Hornsea Mere N & P
- Oak Mere N & P
- Rostherne Mere N & P
- West Midlands Mosses N & P
- River Clun N & P
- River Avon (Christchurch) P
- Somerset Levels & Moors P
- River Itchen P
- River Axe P
- River Camel P
- River Lambourn P
- River Lugg P
- River Mease P
- Peak District Dales P
- Roman Walls Loughs P
Or go back to the main NutrientMonkey calculator.
Wider planning support
Nutrient neutrality is rarely the only condition on a scheme. Our energy statements service and the wider SAP & compliance team cover the rest of the planning and Building Control picture — get a quote and we'll talk it through.