Project pathway
The quickest route to the right decision.
Ordnance surveying in municipal road construction
When a municipal road is reconstructed, working spaces, traffic and access often change from section to section. Earthworks on the carriageway, footways, drainage and crossings may affect different areas and depths. FONTANA-EOD coordinates the survey scope with the planned ground interventions and the construction sections accessible at each stage.
State chainages and sides of the road.
Take additional low points into account.
Coordinate access and surveying.
Context
Compiling the construction plan and depths of ground intervention
In municipal road construction, the survey task is derived from the section, side of the road, excavation and additional low points. Existing reports are assigned to these interventions and compared with access conditions during the respective traffic phase. FONTANA-EOD then agrees with planners and site management which technical steps are necessary before the affected earthworks.
Investigation task
Check existing findings against new interventions
Define the planned work in the ground
Roadworks may range from resurfacing to complete reconstruction with sewers, lighting and new ancillary areas. These alternatives pose different questions for ordnance checks. Information is therefore needed on the actual excavation and all additional components installed in the ground. The overview of Road construction and civil engineering classifies these ground interventions by alignment, depth and construction phase.
Selecting survey services for the planned road reconstruction
Apply existing conclusions to the appropriate areas
A street name or total length is insufficient as a basis for work. Chainage, side of the road, cross-section and construction phase help relate existing documents to the planned ground interventions. This is particularly important if individual sections were surveyed or renewed earlier.
Assigning existing conclusions to individual road sectionsProject types
Road cross-section, crossings and construction phases
Renewal within the existing cross-section
Even within an existing road, the carriageway, footway, parking strip and drainage may have different working depths. The survey therefore does not follow section length alone. Cross-sections, excavation limits and details of deeper individual tasks are needed. Earlier utility construction reports may describe parts of this but do not automatically cover all remaining areas. Preparation clearly distinguishes what has already been surveyed from the additional ground affected by the new road commission.
Determining survey scope by cross-section and depth
Widening and a changed road alignment
If kerb lines, footways or cycling facilities move, new margins may be affected. These areas should be identifiable in the comparison of existing conditions and design. The same applies to new slopes and connections with neighbouring areas. The survey area follows the earthworks actually required, including working spaces. The finished paved surface may be too narrow a basis if additional areas must be worked on or supported during construction.
Clarifying new margins using the plans
A utility package with crossings
Joint roadworks often combine different utility tasks. Each proposed trench and excavation is added to the section plan with its position and depth. This shows which road construction survey also covers a utility section and where additional tasks arise. A shared construction period does not yet establish a shared survey scope. At handover, conclusions are assigned to the respective ground interventions even if several companies work on the same road section in sequence.
Assigning utility work in the road corridorPrepare the decision
Prepare the next work step technically
The traffic phase changes
Before the change, access and newly available working spaces are compared. The technical survey may have different boundaries from the traffic closure; both must be clearly assigned in the programme. A traffic diversion may make work areas accessible that were inaccessible during the previous phase. For these areas, available results and the survey still needed are clarified separately. Carriageways, footways, verges and early connection work must be distinguished. Site management describes which areas will actually be available to the specialist contractor during the next phase. Technical assessment relates to those conditions and the planned interventions. If the position or extent of the closure changes later, its relationship to the survey area is checked again. A section closed to traffic has not thereby been fully assessed technically. Conversely, a survey report does not set traffic regulations for the construction site.
A crossing is added
The additional alignment is described with its position, depth and details of excavations or working spaces. It is compared with existing results rather than merely entered as another item in the construction schedule. For a crossing added later, the new route and its connection to existing utilities are shown on the current plan. The alignment itself, connection excavations and necessary working spaces may affect different areas. For comparison, what matters is which of these areas were actually surveyed and the depth reference of the results. An older report for the road structure does not automatically answer this question for a connection to the side. The sequence of utility work and further construction is also stated. The specialist contractor can then clarify whether existing conclusions suffice, what information is missing and whether an additional survey needs preparation before the new intervention.
One section is already complete
Documentation for the completed section is retained with its boundaries. Adjoining remaining areas and connections to be constructed later are not treated as surveyed simply because of their proximity. Handover identifies the section treated, plan version used and associated limitations. This includes areas left outstanding because of installations or lack of access. If a connection is built only after the diversion, it is assigned to the later task. When a construction company changes, the report and appendices are therefore passed on together. Brief information that the construction phase is complete does not replace these technical details. Before planning, subsequent site management checks whether the intended work lies within the area actually described. New margins, larger excavations or relocated working spaces are reported for assessment. The transition between sections thus remains a traceable handover of specific results.
Project-specific tasks
Recording the carriageway, utilities and construction boundaries on the plan
01
Carriageway and ancillary areas
Describe construction separately for the carriageway, parking strips, footways and cycleways. Widening or changed kerb lines may affect previously untouched margins. Existing survey findings are therefore not extended to the entire new road cross-section without checking.
02
Utilities and crossings
Supply utilities, property connections and road gullies may intersect with the main construction programme. Their trenches, connection excavations and low points are added to the section plan. A utility symbol alone does not describe the depth and width of excavation for the connection.
03
Traffic management and working space
Working on one half of the road at a time changes the available survey area. Clarify which areas are accessible in each phase and where vehicles, barriers or storage areas restrict work. The traffic order and technical survey planning are coordinated but remain different tasks.
04
Transitions between sections
Old and new conditions meet at construction boundaries. Temporary connections, early crossings or remaining areas treated later must be identifiable in the documentation. A completed section does not automatically mean that adjoining working spaces have also been surveyed. The evidence page explains how the documentation of surveyed areas brings areas, depths and limitations together.
Project documents
These documents connect the instruction and result
Chainage and side of the road
Reports and plans are linked with chainages, the side of the road and section boundaries. Where designs change, it remains clear which part is meant. A street name alone is too imprecise, particularly for longer projects or work spread over several years. Each report section clearly identifies where the relevant stretch starts and ends and which side or ancillary area is covered. If a later plan uses different section names, their relationship to the earlier information is clearly established. Overview and detail plans complement each other: the overview locates the section within the works, while the detail plan shows actual boundaries and survey positions. Unclear assignments are clarified before results are adopted. This also matters when work resumes after a long interruption and new parties use old appendices. The spatial assignment is retained with the result rather than replaced by a street name alone.
Cross-sections with low points
The standard cross-section is supplemented by local deepening, utilities and connections. The information must describe the actual ground intervention. An average excavation depth must not obscure locally deeper work. Local excavations, chamber areas or connections are shown in relation to the standard construction depicted. The design identifies the affected positions and the intended depth reference. Where the surface changes, a check establishes whether elevations used earlier still describe the same reference level. Differences are reported to the specialist contractor for assessment before an older result is used for the new intervention. Even a long continuous alignment may contain different local tasks. The survey scope therefore relates to actual work rather than being derived solely from an average depth. The cross-sections used and their assignment to individual areas remain identifiable in the documentation.
Transitions and remaining strips
At section boundaries, untreated areas and temporary connections are identified. The next construction phase can build on this. Scheduled completion of a section is not equated with a conclusion about neighbouring volumes of ground. Tasks to continue from the preceding section are recorded for the next construction stage. An outstanding margin receives a specific spatial reference and remains distinguishable from areas already treated. If the intended construction of a connection changes, that change is compared with available results. Information passed to site management and subsequent trades therefore covers both the completed part and outstanding questions. Interim statuses are dated individually. After an additional survey, it remains clear which previously outstanding issue it answers. The project file can thus support later changes or repairs without retrospectively extending the original survey boundaries.
Construction phases
Keep construction phases and changes traceable
Technically preparing work on one half of the road at a time
Surveying one side of the road is coordinated with conditions on the other side and available access. Construction machinery, traffic management and material storage may alter measurement conditions. The programme therefore records which area is actually accessible in each phase and which task can then be performed. A complete section plan helps avoid overlooking remaining strips or transitions when traffic arrangements change. Unchanged surveyability across all phases is not assumed.
Bringing property connections forward
A property connection may be worked on before the rest of the road structure. For this task, the trench, connection excavation and necessary working space are described separately. Existing survey findings for the main alignment are compared with it. If the connection lies outside the area considered or extends deeper, the additional need remains outstanding until technically clarified. For the later road construction phase, results of the early work are incorporated into the shared documentation with an unambiguous position and limitations.
Road maintenance involving later excavations
After reconstruction, utility repairs or new connections may become necessary. Existing reports are usable where their plan references and depth information have been retained. A later excavation is compared with this documented scope. Different trench positions, deepened chambers and additional shoring may raise new questions. The body responsible for maintenance should therefore receive not only a completion note but also the spatial boundaries and limitations stated in the report.
Documentation
Evidence for civil engineering and subsequent road maintenance
Assign the results to the project
A section report should remain spatially identifiable after the construction site closes. Chainages, coordinates, plan references and identifiable remaining areas facilitate later repairs or new connections. Information must match the scope treated; a report about a utility trench is not an area-wide conclusion for the entire road. Following actual exposure or clearance work, the associated findings and clearance records are included.
Coordinate tasks and further works
If the traffic phase or utility plan changes, a brief comparison is useful: do new ground interventions arise, are earlier boundaries exceeded or does access change? Site management and specialist planners clarify these changes with the ordnance specialist contractor before the affected work.
Next steps
Coordinating surveying and traffic management
Describing road sections
Compile chainages, cross-sections, excavation depths and additional utility work with an unambiguous plan version.
Assigning reports to individual stretches
Relate old reports and plans to the affected stretches; mark margins not covered. Where historical questions about those stretches remain open, the necessary sources are researched and aerial photographs spatially assessed. Findings are assigned to the present road sections and ground interventions and used for survey planning.
Coordinating survey dates
Coordinate survey windows with traffic diversions, setup of work areas and intended preparatory work. The suitable survey method is defined for the respective ground interventions and site conditions.
Carry out the investigation
The commissioned survey is carried out within the defined area. Measurement data, findings and limitations are recorded with location, depth and plan references.
Assess results
Measurement data and findings are assessed by specialists. Outstanding areas, necessary follow-up surveys and the next decision are identified for designers and site management.
Handing surveyed sections over to site management
Record for execution which section was surveyed, with which limitations, and what remains outstanding.
Technical assessment
Checking where measurements are possible
Metal and utility density
Covers, utilities, fences and reinforced structures may affect measurement results. Existing plans and an on-site record help assess such influences. The conclusions achievable depend on the particular road corridor, rather than the selected measurement method alone.
Technically coordinating preparatory work
Lifting paving, removing installations or performing preparatory earthworks may already affect an area not yet sufficiently surveyed. Necessary surveys and protective measures are planned before ground interventions during vegetation clearance, surface removal, removal of installations or creation of work areas and access routes. Sections accessible later are surveyed before the respective subsequent interventions. An unobstructed area desired for measurement must not be created through unchecked ground interventions.
Survey during construction
Where a necessary assessment cannot be completed in advance, the subsequent procedure is explicitly planned. Merely observing the excavator does not amount to ordnance surveying during construction. The scope and limitations of the service must be clear to site management and the civil engineering contractor.
Method selection
Select methods according to the task and survey conditions
Historical records and aerial photographs
Historical aerial photograph assessment and other old records help place the basis for suspicion in its spatial context. The available images, their evidential value and the limits of the area considered matter. The absence of an identifiable indication must be distinguished from a technically surveyed ground area. The assessment is considered together with the planned intervention and other available findings. It can support the choice of a survey, but is not a measurement of the present-day subsurface or confirmation for all future works.
Understand aerial photograph assessmentMagnetometric survey
Magnetometric methods detect magnetic anomalies. Whether they can address the specific survey task depends, among other things, on the expected objects, ground conditions, interference and required survey area. Fences, utilities or existing structures may affect interpretation. A measurement signal is therefore not described as ordnance solely because of its strength. Method, interpretation and any further investigation are planned as a connected specialist task.
Understand the scope of magnetometryElectromagnetic methods and TDEM
Electromagnetic surveys may be suitable for particular metallic targets and site conditions. TDEM detects the time-dependent electromagnetic responses of electrically conductive bodies. Suitability is justified for the particular task, not inferred merely from the availability of equipment. Interfering installations, accessible areas and the required conclusion must also be considered. Results are documented with location and survey conditions. Whether a complementary method is needed follows from the specialist assessment and remains a specific project decision.
Understand electromagnetic surveyingGround-penetrating radar
Under suitable conditions, ground-penetrating radar can provide information about subsurface structures and reflections. Ground conditions, moisture, installations and the particular survey task affect interpretability. An anomaly is not automatically ordnance, and an area with no apparent anomalies is not general evidence for arbitrary depths. The specialist interpretation and its limits are documented with the instruction. A survey for another purpose is not adopted without checking as ordnance evidence.
GPR and limitationsDeep-ground and downhole surveys
For deeper interventions, it may be necessary to check whether a surface survey can provide the required conclusion or whether another approach is needed. Location, depth, borehole layout and existing utilities then form part of preparation. Access for the survey must also be planned appropriately from a technical perspective. A general depth figure or standard grid does not replace this task. Results remain tied to the areas actually treated and the method applied. For surveys from investigation boreholes, casing, drilling depth and documentation are also coordinated with the task and local conditions.
Prepare deep interventionsSurvey during construction
If a necessary preliminary survey cannot be completed in full, the suitability of a technically planned approach during construction is assessed. Each working layer is technically surveyed and evaluated before controlled removal in layers with supplementary visual inspection follows. The steps are repeated to the agreed excavation formation. Excavation layers, stop signal, authority to give instructions, reporting channels and documentation are agreed with site management and specialists before work starts. Pure visual observation of the excavation cannot simply replace a necessary instrumental survey. Site management needs a clear description of when specialist works take place, how new findings are handled and which areas remain outstanding.
Agree the approach during constructionWorking approach
How FONTANA-EOD works
Document the agreed specialist service clearly
FONTANA-EOD relates the survey to a described intervention and a traceable set of records. Before work starts, the technical task, accessible areas and required results are agreed. If the design or local conditions change, it is checked whether the agreed scope still fits. The report records the work actually performed and its limits. Further construction planning can thus identify what conclusion is available and where additional clarification remains necessary.
Discuss the investigation taskThe task before the equipment
A survey begins with the required information objective. The method selected is technically justified in relation to it. A particular instrument or a similar neighbouring construction site is not, by itself, sufficient grounds for selecting a method.
Keep limitations visible
Inaccessible areas and limited conclusions are identified. They do not disappear into a total area figure. Designers and site management can then decide specifically which areas still need attention and when a suitable survey becomes possible.
Clarify changes before intervening in the ground
A new location, additional depth or different construction method is compared with previous results. A familiar project name does not replace this comparison. Feedback is provided before the affected work so that an outstanding question can be included in the sequence.
Hand over the report and plan together
The technical conclusion remains connected to its location references and appendices. A brief summary helps orientation but does not replace the documented survey scope. This basis is retained even if site management or contractors change.
Working together
Distinguish the tasks of client, designers and specialist contractor
Client and operator
The client describes the project and provides the available project records. The operator adds requirements for use, access and timing. A coordinating contact brings the parties together; individual tasks remain assigned to the named parties. Before commissioning, it is clearly recorded what information is missing, who will obtain it and what decision the result is intended to prepare.
Planning and construction management
The specialist designers describe areas, depths, construction methods and changes. Site management coordinates the planned sequence with the construction contractors and agreed specialist works. Results are assigned to the respective intervention. A technical plan change is communicated early enough for its effect on the survey task to be assessed before construction. Organisational construction stage boundaries remain distinguishable from technical survey boundaries.
Specialist company and competent bodies
The private ordnance specialist contractor carries out the agreed survey and documentation scope. Authority requirements and decisions are clarified with the respective competent bodies. The records needed for a particular procedure depend on the site and project. The technical report documents the specialist service performed, including its area, depth and service scope and the limits of its conclusions. Applicability to further groundworks is checked against the specific intervention. Administrative decisions are made by the competent authorities.
In Germany, the Länder ordnance disposal services and locally competent authorities perform hazard prevention and find-handling tasks. Their involvement and the tasks of the public order authority and, where applicable, building control are clarified for the project location. Outside Germany, local responsibilities apply. Contacts, conditions and reporting channels are assigned to the construction project concerned.
Requirements
Clarify technical requirements and responsibilities within the project
In Germany, § 7 SprengG concerns the commercial authorisation for activities requiring authorisation; § 20 SprengG concerns the certificate of competence of responsible persons. Under § 1b SprengG, searching for found munitions also counts as handling them. The requirements applicable to the project depend on the activity actually commissioned and the allocation of responsibilities.
The First Ordinance to the German Explosives Act (1. SprengV) includes requirements for specialist knowledge and state-recognised courses. For municipal roadworks, the necessary qualification follows the survey or clearance task actually commissioned and the volumes of ground affected.
DGUV Information 201-027 concerns protective measures during ordnance clearance work. DGUV Rule 113-003 concerns the dismantling or destruction of explosives or corresponding objects and also includes the disposal of found munitions. It applies according to this field of activity; it does not replace a risk assessment specific to the planned ground intervention.
Relate requirements to the specialist task
For the commissioned activities, the relevant technical requirements and questions of permits, competence certification and responsibility are clarified. The actual planned service scope is decisive. A general company designation does not replace checking that the tasks and interfaces are described appropriately for the specific project.
Link occupational safety to the construction sequence
Risk assessment, work areas and communication must suit the proposed activities. Ordnance specialist works are coordinated with the other construction activities. Operational organisation, traffic safety and other specialist technical inspections retain their own responsible parties. Joint coordination brings the information together without equating the different tasks.
Use technical findings correctly
A measurement anomaly first requires specialist assessment; its depiction alone does not identify it as ordnance. If an object is suspicious, work in the affected area is stopped; the competent authorities determine further measures. Survey reports identify the scope treated and its limits so that results are not extended to unchecked areas or later plan changes. Necessary follow-up surveys or exposure works are assigned to the area concerned. Recovery of confirmed ordnance is coordinated with the permitted activities, local responsibilities and documentation.
Planning and documentation: BFR KMR: clearance planning, principles · BFR KMR: geophysics · BFR KMR: documentation · DGUV: ordnance clearance FAQ
The federal construction guidelines on ordnance clearance contain requirements for historical and technical investigation, clearance concepts, procurement and documentation within their defined area of federal responsibility. Their application to the specific municipal road project, together with local requirements and responsibilities, is clarified separately.
Project site
Connect the site with the specific construction task
Site and existing requirements
Provide the actual site with a plan and affected properties. Existing information, requirements and reports are assigned to this area. Regional requirements must be established for the specific project; showing a service area does not promise a particular official service or an investigation already completed. The regional overview provides orientation, while the plan and documents determine the technical task.
Understand the results
Use technical statements for the next decision
Read results together with their scope
A statement is understandable only with its investigation task. Check the area and depth described, methods used and restrictions. A report title or single result line is insufficient. For new work, these details are compared with the current plan to establish which knowledge remains usable and which question is unresolved.
Explore results and terminologyUse project terminology unambiguously
Document review, surveying, construction-phase specialist work and recovery are different tasks. An enquiry need not identify the correct method in advance. An accurate description of the intervention and required decision is more useful. This establishes the appropriate technical scope and prevents a general term from meaning different things in design, procurement and execution.
Understand the service scopeDocuments and execution
Consider records and surveying together
Assign records to their locations
For preparation, the location plan and available findings are considered together. Assessment of historical records addresses a different task from a technical survey of the present-day subsurface.
Explore the historical basisUse results for construction planning
Survey scope, plan references and limitations are documented together. Site management can identify the specific conclusion available for the next intervention.
Understand documentation
Further technical topics
Find the appropriate specialist service and project arrangements
Compare municipal project types
Other municipal projects may include additional interventions and interfaces. The overview helps classify them without anticipating the survey of a specific site.
Understand municipal projectsSelect the specialist service according to the task
Document assessment, instrumental surveying, supervision during works and recovery are distinguished by their respective purposes. A technically justified selection connects the information sought with the actual conditions.
Compare servicesQuestions from planning
Frequently asked questions about municipal road construction
Is resurfacing alone treated in the same way as full-depth reconstruction?
No. The actual ground intervention must be distinguished. Excavation, installations and existing findings are decisive. If new gullies or utilities are installed in parallel, they may create different requirements from the carriageway surface.
Can surveying take place section by section?
Yes, if the technical task and available areas allow this approach. Survey boundaries, construction boundaries and transitions must be clearly documented. The result for a surveyed section does not automatically apply to the adjoining unchecked area.
Why do property connections and crossings matter separately?
They often leave the main alignment or extend to different depths. Connection excavations and working spaces also form part of them. Without this information, a survey may remain limited to the main road cross-section even though additional earthworks are planned.
What should be done if a suspicious object is found during earthworks?
If an unexpected suspicious object is found, stop work in the affected area immediately. Do not touch, move or uncover the object further. Leave the immediate area and keep others away without putting yourself at risk. In Germany, notify the police immediately on 110; outside Germany, use the local emergency reporting procedure. The competent authorities determine what happens next. Inform site management and the client; internal reporting must not delay the emergency call.
What happens if a construction boundary is moved later?
The new boundary is compared with the documented survey area. If additional area or depth is affected, the need for further specialist work must be clarified before work takes place there.
Can surveying simply follow the traffic closure?
The closure is an important organisational constraint but does not alone define the technical survey scope. Measurement conditions, depths of ground intervention and necessary working spaces are also assessed. Survey boundaries and traffic phases are coordinated so that their different meanings remain identifiable.
How are utilities from different network operators taken into account?
Each planned ground intervention is added to the shared section plan with its position and depth. Existing results are related to it. Technical conclusions remain tied to the scope actually surveyed, even if several utility operators work during the same period or under the same traffic arrangements.
Which information particularly affects effort and costs?
The areas and depths treated, ground composition, utility density, access, interference and number of survey phases are essential. The quality of existing documents and required documentation scope also matter. General costing based solely on road length does not reliably reflect these differences.
Project enquiry
Send the construction plan and cross-sections
Plan revision and decision deadline
Specify whether the project is at an early planning stage, being prepared for procurement or already approaching an intervention in the ground. The date by which a technical conclusion is required helps coordination. Outstanding information is communicated expressly rather than replaced with assumed values.
For initial coordination, useful documents include the construction plan, cross-sections and construction phase plan, together with existing utility and ordnance documents. Mark crossings, connection excavations and proposed changes to ancillary areas. Also state the next date for traffic arrangements or civil engineering procurement. Add which road areas are actually accessible during the intended time window and where work becomes possible only after a further traffic diversion.
Section length and distribution, local depths, surfaces and known obstructions matter for assessing effort. A contact for the plan version and construction phases helps assign this information. Crossings or connections not yet decided are marked as outstanding. The specialist contractor can thus distinguish the survey scope initially needed from later tasks not yet fully described.
If results are to inform a tender, identify the required handover date separately. Clarify which technical information should enter the tender documents and which execution questions still depend on later planning decisions.
Assign records to their locations
Send the site plan and available reports with their associated appendices. For multiple construction stages, indicate which document relates to which area. Photographs supplement descriptions of access and existing conditions; they do not replace information on underground structures or planned depths. An old utility plan is an important document but does not replace assessment of the suspected hazard and may be incomplete. It is considered together with the current construction plan, existing surveys and site conditions.
Sewer renovation within the existing network
Preparing sewer workInner-city squares
Preparing square reconstructionProcuring the specialist service
Prepare tendering
Have your project assessed
Whether historical aerial photograph analysis, explosive ordnance surveying, surface surveying using GPR, magnetometry or TDEM, deep-ground surveys, downhole surveys, excavation supervision, area clearance or ordnance recovery is needed depends on the location, ground disturbance, depth, ground and existing documents. An early ordnance assessment provides clarity for tendering, programming, occupational safety and construction.
FONTANA-EOD combines its Section 7 SprengG licence, specialists holding Section 20 SprengG certificates of competence, suitable survey and clearance methods, and traceable documentation. Send the site plan, depth of ground disturbance, construction phase and existing documents for an initial technical assessment.
