Further to the principles of the business case information available, the following sets out the detailed business case with a relevance to Highways practitioners.
The detailed business case (DBC) confirms an activity that comes from the detailed programme of activities and confirms the overall assessment profile. It includes a detailed reporting of economic, financial and commercial aspects of the activity built upon the strategic/ programme/ indicative business case.
The DBC should be completed before commencing the detailed pre-implementation (including detailed design, property acquisition, consenting or construction) of the activities. It is recognised that whilst activity specific guidance may be used to inform the options considered as part of the DBC, designs should not be progressed past this level until the DBC is complete and decision makers make their informed choice of the option(s) to be taken forward to implementation.
Appraisal of alternatives and options and production of a DBC should precede any commitments to the project. This ensures the proper consideration of the transport issues relative to the proposals being developed and presentation of these aspects in a clear manner.
Detailed assessment of the option/s is carried out in the DBC which have been taken forward from the previous business case phase, with specific consideration given to:
Each business case needs to clearly articulate how the recommended programme or option will address the identified problems through the agreed investment objectives. By this phase of the business case problems, benefits, SMART investment objectives, measures, baselines and expected outcomes should all be set. Benefit realisation needs to be considered through each phase of the business case.
See the Detailed business case overview [PDF, 60 KB] for more information.
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Ensure investment objectives and a monitoring plan that includes developing SMART investment objectives, including KPIs, measures, baseline data and expected outcomes are developed. This may have been undertaken at an earlier phase, but detail should be added as relevant.
Confirm the investment objectives and assess the preferred option(s) against the investment objectives. This is typically done to a greater level of detail and at the more focused activity level than during a programme business case.
Complete project benefit mapping to the activity level, which should create a clear line of sight between project problems, benefits, investment objectives, measures and KPIs.
Finalise the investment objectives and update the project monitoring plan to reflect any developments or improved evidence, using it as a base for completing the benefits realisation framework. Secure key stakeholder, project team and measure owner acceptance as relevant (as part of the management case), then upload the completed benefits realisation framework to TIO.
If this is part of a wider programme business case, revisit the problems and benefits of the programme and determine the contribution made to the programme level investment objectives by the detailed business case. Document this in the monitoring plan. Update the programme business case if necessary to reflect benefit realisation.
Further information available at the benefit realisation page.
Records of quality assurance and approvals should be undertaken in accordance with the System Design and Delivery project assurance and approvals process.
There are also check in points [PDF, 180 KB] to keep in mind through a detailed or single stage business case. One check point is mentioned with an investment quality assurance (IQA) based on 12 of the 16 investment questions. The rationale for the check in and IQA is to provide assurance the business case is on the right track, the quality is high, and there is wider organisational buy in to the short listed options prior to public consultation.
For each phase of the business case process there are technical requirements that may be relevant to your project that will need to be considered and included in addition to general guidance and templates. Aligned to the business case philosophy, suppliers are required to meet more technical requirements as an activity progresses through the business case phases.
Outlined below are the technical requirements for completing the detailed business case, by subject matter.
Suppliers are required to comply with these requirements except where varied within the scope of a contract.
For further information or advice, contact the relevant team.
Subject matter | Technical requirements | Information | Contact |
Asset management | SM018 whole of life costs - NPV, IAMP, LAMPs | Asset Management team | |
Community and stakeholder engagement | Update community engagement plan based on outcomes of the IBC | Community and stakeholder engagement | Environment team |
Prepare consultation report on engagement process, outcomes. This report will be used to support applications for statutory approvals | |||
Economics | Economic viability tables 8.1 and 8.2 of DBC template - detailed benefits and BCR of options | Economic evaluation manual | Economic Evaluation team |
Outcome delivery - detailed benefits by benefit type | |||
Risk analysis table 8.3 of the DBC template - sensitivity testing | |||
Electric vehicle public charging infrastructure |
Consider requirements to allow electric vehicle (EV) drivers to charge their vehicles while using state highways and local roads Other emerging technologies should also be considered at this stage |
Technical advice guidance | EV Programme team |
Environment and social responsibility | Update Environmental and Social Responsibility Screen |
Refer completed screen |
Environment team |
Prepare preliminary technical assessments (if required) | Impact assessment guides and the consenting strategy for the project determine level of detail required for environmental or social technical assessments | ||
Prepare consenting strategy | Consenting strategy and approvals pathway guide and consenting strategy template | ||
Ensure preliminary design statement incorporates screen results, results of any preliminary technical assessment and consenting strategy including suggested mitigation by:
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State highway environmental plan | ||
Scope environmental and social technical assessments to support consenting strategy | ESR Standard explanation | ||
Geotechnical | Preliminary geotechnical appraisal report | Requirements currently detailed in SM030 | Structures team |
Geotechnical testing and assessment undertaken with results presented in a Geotechnical assessment report (factual report) and interpreted in a Geotechnical interpretative report | |||
Assumed design parameters for subgrade strength and fill and cut batter slopes presented in Preliminary design philosophy statement | |||
Pavements | Pavement design required - not at detailed design level |
NZ supplement to the 2004 Austroads pavement design guide Austroads Guide to Pavement technology: Part 2, Pavement Structural Design(external link) Sections to consider: 3, 5, 6, 7, 8, 10 |
Pavements team |
Property | Acquisition agent to negotiate access to specific parcels of land. Compile due diligence information and update the risk assessment for each. Surplus property is incorporated into the 5 year disposal programme | Property team | |
Risk | As the project lifecycle transitions through the business case phases the increasing maturity of programme data and clarity of understanding should be reflected in an increasing depth of maturity in the level of risk management data and application of risk management practices | Project risk management | Risk team |
Road safety | Road safety audit - concept audit | Road safety audit procedures | Safety team |
Design - review of compliance with guidelines - exception report | |||
Statutory approvals | Prepare preliminary planning assessment of relevant planning and statutory framework | Environment team | |
Prepare preliminary technical assessments (as required) | Subject matter impact assessment guides | ||
Evaluate consenting package options and the different decision making pathways Prepare consenting strategy If EPA process preferred, refer to NZTA-EPA relationship protocol Prepare preliminary assessments of alternatives, consultation report and statutory consultation requirements |
Consenting strategy guide |
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Scope environmental and social technical assessments to support consenting strategy | Impact assessment guides will help prepare scope | ||
Structures | Preliminary structure options report(s), developed to identify alternative options for bridges and other highway structures (category 1 and 2 structures only), to be included within the Preliminary design philosophy statement |
Bridge manual appendix F |
Structures team |
Transport modelling | Economic viability - detailed benefits | Transport model development guidance | Design Practice and Solutions team |
Title | Type | Document | |
Detailed business case document | Template | Word [DOCX, 188 KB] | PDF [PDF, 4.9 MB] |
IQA cover sheet for Project Owner to complete available from SDDOPPP.delegations@nzta.govt.nz |
Title | Download |
P&I knowledge base develop detailed business case | Website link |
IBC/DBC check in point | PDF [PDF, 180 KB] |
Benefits realisation framework | PDF [PDF, 112 KB] |
For further information contact designpracticesolutions@nzta.govt.nz.