Evaluate Nature-Based Solutions Designer candidates across 4 weighted areas: technical depth, work that shipped, diagnosis under uncertainty, and working across the org. Technical depth leads at 35%, so check command of hydrology and ecology fundamentals: SuDS design to CIRIA SuDS Manual, infiltration testing, planting palettes, biodiversity net gain metrics, natural flood management. Use the rubric to compare role-specific evidence consistently.
For technical depth, look for evidence the candidate names design standards and species selections precisely, explains infiltration rates, attenuation volumes and BNG unit calculations without hedging. For work that shipped, look for evidence the candidate cites named sites with area, cost per hectare, and post-construction monitoring showing establishment rates or measured runoff reduction.
Apply the written 1–5 anchors to every answer, record the evidence behind each rating, and use the factor weights to reach a consistent overall assessment.
Complete evaluation framework
What to assess and how to score it
Review the evidence signals before interviewing. Then use the anchored descriptions—not instinct alone—to choose the score that best matches each answer.
01
Evaluation factor
Technical depth
35% weight
Check command of hydrology and ecology fundamentals: SuDS design to CIRIA SuDS Manual, infiltration testing, planting palettes, biodiversity net gain metrics, natural flood management runoff calculations.
Evidence to listen for
Explains the physics or mechanism behind their work, not just the tooling
Names the standards, tolerances, and constraints they designed against
Can defend a design decision under follow-up questions
Distinguishes what they personally engineered from what the team delivered
Five-point scoring guide
1
Poor
Cannot explain the fundamentals of their own stated specialism.
2
Needs Improvement
Knows the vocabulary but not the underlying mechanism; struggles under follow-ups.
3
Satisfactory
Solid working knowledge for the role; depth thins out on edge cases.
4
Very Good
Strong command of the domain; explains trade-offs and defends decisions well.
5
Excellent
Names design standards and species selections precisely, explains infiltration rates, attenuation volumes and BNG unit calculations without hedging.
02
Evaluation factor
Work that shipped
30% weight
Probe schemes built on the ground: rain gardens, bioswales, leaky dams, saltmarsh or peatland restoration, with hectares, catchment area treated and monitoring results after two seasons.
Evidence to listen for
Names specific programmes, parts, or systems that reached production or field use
States their own scope inside the project
Can give measured outcomes: yield, cycle time, cost, failure rate
Explains what went wrong and what they changed
Five-point scoring guide
1
Poor
No delivered work; experience is coursework, lab-only, or purely observational.
2
Needs Improvement
Contributed to projects but cannot say what shipped or what their part was.
3
Satisfactory
Has delivered real work; outcomes described without numbers.
4
Very Good
Names shipped work and their scope, with some measured results.
5
Excellent
Cites named sites with area, cost per hectare, and post-construction monitoring showing establishment rates or measured runoff reduction.
03
Evaluation factor
Diagnosis under uncertainty
20% weight
Test how they handled failures: plant die-off, clogged filter media, unexpected groundwater, contaminated ground, or a scheme underperforming against modelled flood benefit.
Evidence to listen for
Describes a real failure they chased to root cause
Shows a method: isolate variables, reproduce, measure, eliminate
Distinguishes correlation from cause
Says what they ruled out and why, not only what the answer turned out to be
Five-point scoring guide
1
Poor
No diagnostic method; guesses or escalates immediately.
2
Needs Improvement
Trial and error with no structure; cannot explain how they narrowed the cause.
3
Satisfactory
Reasonable method on familiar problems; less structured on novel ones.
4
Very Good
Clear systematic approach with a real root-cause story.
5
Excellent
Walks through a specific failure, the diagnostic steps taken (soil sampling, hydraulic recheck) and the design change that fixed establishment or performance.
04
Evaluation factor
Working across the org
15% weight
Assess coordination with drainage engineers, landscape architects, planners, Environment Agency or lead local flood authority, plus maintenance teams inheriting the asset.
Evidence to listen for
Explains technical constraints to non-technical stakeholders without condescension
Has negotiated scope, cost, or timeline with manufacturing, product, or suppliers
Documents decisions so others can act on them
Takes review feedback without defensiveness
Five-point scoring guide
1
Poor
Cannot communicate outside their specialism; dismissive of other functions.
2
Needs Improvement
Communication gaps cause rework; avoids stakeholder contact.
3
Satisfactory
Works adequately with other teams; documentation is thin.
4
Very Good
Communicates clearly across functions; reliable collaborator.
5
Excellent
Describes resolving a concrete conflict between civil engineering constraints and habitat aims, and how maintenance regimes were agreed before handover.
Evidence-led prompts
Interview questions for a Nature-Based Solutions Designer
Use these prompts to surface evidence for the weighted factors above and compare candidates against the same role-specific criteria.
01
Can you describe a project where you delivered a nature-based solution?
02
Can you discuss your experience with green infrastructure in urban settings?
03
Can you give an example of using these approaches to improve biodiversity?
04
How do you assess whether a nature-based approach suits a particular site?
05
How do you approach the selection of plant species for a project?
