Infrastructure Design Proposal

Proof required

Submit: (1) a problem statement (150–200 words) defining the infrastructure need, the users, and the design life; (2) a site assessment summary — a structured description or table of: topography, land use, hydrological conditions, ground conditions, and utilities or existing infrastructure; (3) a constraints summary listing at least five design constraints (physical, regulatory, or environmental) with the source of each constraint; (4) a site location map (OpenStreetMap screenshot or equivalent, annotated to show the site boundary and key features).

What gets checked

• Each design constraint cites its source — 'maximum structure height 8 m above existing ground level (local planning authority height restriction, planning reference XYZ)' is a valid constraint; 'height is constrained by planning' is not
• Site assessment distinguishes between confirmed data and assumed data — 'ground conditions assumed as stiff clay based on BGS 1:50,000 geological map (Sheet 256); site investigation data not available' is a valid qualified statement; presenting assumed ground conditions without qualification is misleading
• At least five constraints are listed from at least two different constraint categories (physical, regulatory, environmental, operational, budgetary) — a constraints list that is entirely physical constraints has not considered the full design context

Common mistakes

• Selecting a scenario without publicly available site data — a remote site with no topographic data, no geological maps, and no flood mapping cannot be characterised from free sources; choose a scenario near available data coverage or use a well-documented reference site
• Treating design standards as constraints rather than as the design framework — Eurocode EN 1990 is not a constraint; it is the design framework; a constraint is 'the bridge must clear the 100-year flood level of 3.2 m above channel invert, per the Environment Agency flood map'

Resources

What a verifier looks for

• Engineering Design Triad: M1 produces a design artifact (site assessment with annotated map and constraints summary) — this is the first of three artifact types required across M1–M3.
• Design constraints must cite their source — check that each constraint links to a planning document, a flood map reference, a utility record, or a physical measurement.
• Site assessment must distinguish confirmed from assumed data — check that assumed ground conditions or hydrological parameters are qualified as assumed.
• Constraints must span at least two categories — check that not all five constraints are of the same type.
• Reviewer must be a civil or structural engineer — site assessment completeness and constraint identification require discipline-specific experience.

Proof required

Submit: (1) concept sketches or plan drawings for all three options (draw.io exports or hand-drawn scans — clearly labelled with dimensions and structural form); (2) the weighted scoring matrix (options as columns, criteria as rows, with weight per criterion, raw score, and weighted score for each option); (3) a preferred option statement (150–200 words) explaining why the highest-scoring option is preferred, including one risk or limitation of the preferred option that the scoring matrix did not fully capture.

What gets checked

• Three options differ in a meaningful engineering respect — three bridges with the same structural form but different spans are not three distinct options; distinct options might be: Option A (reinforced concrete frame bridge), Option B (steel truss bridge), Option C (cable-stayed bridge) — different structural forms with different cost, programme, and maintenance profiles
• Weighted scoring matrix assigns different weights to criteria and shows the calculation — 'Technical Feasibility: weight 30%, Option A raw score 7/10, weighted score 2.1' is a valid matrix entry; an unweighted matrix or one without calculations presented cannot be verified
• Preferred option statement acknowledges a limitation — a statement that only describes why the preferred option scored highest, without naming a risk or limitation not captured in the matrix, has not demonstrated critical evaluation

Common mistakes

• Developing options that are variations of the same scheme rather than genuinely distinct alternatives — the options must be different enough that a change in site conditions, budget, or programme constraint could change the preferred option; variations in span length alone do not satisfy this
• Using a scoring matrix without assigning weights — an unweighted matrix treats all criteria as equally important, which is rarely true in infrastructure design; the weights are where the design judgement is exercised

Resources

What a verifier looks for

• Engineering Design Triad: M2 produces a design artifact (concept sketches for all three options) and an analysis artifact (weighted scoring matrix with calculations) — both must be present.
• Three options must differ in a meaningful engineering respect — check that the structural form, material, or alignment differs, not just the scale.
• Weighted scoring matrix must show weights and calculations — check that weights are assigned and that the weighted score calculation is shown for each cell.
• Preferred option statement must acknowledge a limitation — check that a risk or limitation not captured by the matrix is named.
• Reviewer must be a civil or structural engineer with infrastructure design or options assessment experience.

Proof required

Submit: (1) the complete infrastructure design proposal (all sections above, 1000–1400 words plus drawings); (2) the risk register table (risk, probability Low/Medium/High, impact Low/Medium/High, risk rating, and mitigation); (3) a written record of the reviewer's two challenges and your responses (250 words minimum, attributing reviewer by professional role and relevant infrastructure experience).

What gets checked

• Preliminary cost estimate states its accuracy — '±30% order-of-magnitude estimate based on RICS elemental cost rates; suitable for funding approval, not for contract award' is a valid cost estimate statement; a number without a stated accuracy implies a false precision
• Risk register mitigation measures are specific — 'risk: unexpected ground conditions during excavation; mitigation: commission a site investigation (trial pits and boreholes) at the next project stage to confirm ground conditions before detailed design' is a valid mitigation; 'manage ground risk' is not
• Reviewer challenges cover both the options assessment and the preliminary design — a review that only challenges one aspect has not assessed the full proposal; both must appear in the review record

Common mistakes

• Omitting the risk register — infrastructure design proposals always include a risk register; a proposal without one is missing the primary tool for communicating project uncertainty to decision-makers
• Presenting the cost estimate without a stated accuracy band — a cost estimate at proposal stage is inherently uncertain; presenting a single number without acknowledging the ±30% or ±50% uncertainty misleads decision-makers about the reliability of the estimate

Resources

What a verifier looks for

• Engineering Design Triad check: M1–M3 together produce a design artifact (site assessment drawings + options sketches + preferred option preliminary design drawing), an analysis artifact (options assessment scoring matrix + risk register), and a documentation artifact (complete infrastructure design proposal with cost estimate and programme) — confirm all three types are present.
• Cost estimate must state its accuracy band — check that ±30% or equivalent is stated explicitly.
• Risk register must have specific mitigations — check that each mitigation describes a concrete action, not a management intent.
• Reviewer must have challenged both the options assessment and the preliminary design — check that the review record includes both types of challenge.
• Reviewer must be a civil or structural engineer with infrastructure project experience — options assessment evaluation and preliminary design challenge require discipline-specific expertise.
• The Proof Accessibility Rule applies — draw.io, OpenStreetMap, OpenTopoData, BGS/USGS geological data, DMRB, ICE resources, and IPA guidance are all free.