Schematic map labelled Bremen, beside a tablet, hard hat and notebook.

Explosive ordnance surveying in Bremen’s streets

Where will a trench be opened, where will a foundation be installed and which construction phase comes next? Ordnance assessment in Bremen’s streets needs these details in addition to the traffic signs plan. FONTANA-EOD supports the commissioned investigation and records in the report which areas and works the results cover.

Trenches and installation positions

Show position, width and depth on the drawing.

Applications and responsibilities

Coordinate traffic arrangements and ordnance assessment.

Construction sections

Check the relevant report before each intervention.

Discuss a road construction projectOrdnance assessment in Bremen and Bremerhaven
Assess the construction project

Define the traffic area and investigation area separately

For your project in Bremen’s streets, we relate trenches, foundations and access routes to existing results. The intervention drawing shows the positions and depths of groundworks within the traffic closure. Traffic arrangements and technical ordnance prerequisites are coordinated for each construction phase.

Project references

Selected project examples

Project site

Connect the site with the specific construction task

Schematic map with a coat of arms, alongside a tablet, safety helmet and notebook.

Relate the street name to the actual work site

To identify a site within the municipality of Bremen, provide the specific intervention and traffic area affected alongside the street and position. Responsibilities for traffic arrangements follow local requirements for the road network and traffic area used. Explosive ordnance is coordinated separately through the responsible procedure. For works between the city centre and Neustadt or elsewhere in the city, relate the specific intervention area to existing findings there. An infrastructure project at another location is assessed against its own records.

Information on explosive ordnance surveying in Bremen (city) supports preparation of your project enquiry. Documents and planned ground disturbance on the respective property are decisive.

Bremen and Bremerhaven
Local context

Which groundworks are planned within the closure?

Responsibilities for traffic arrangements

In Bremen, responsibility for traffic management orders depends, among other factors, on the road network and traffic area affected. According to the police information, the ASV handles work sites on the designated priority road network (Vorbehaltsnetz); the police handles those on the subordinate network and work sites on the priority network that do not occupy the carriageway. This allocation concerns traffic arrangements. It does not replace separate clarification of explosive ordnance.

Groundworks within the work site

The investigation drawing must show the groundworks. A closed-off pavement area may be larger than the trench planned within it. Conversely, an excavation widened later may extend beyond the area first described. Show on the site plan where ground is to be opened or altered. The outer site boundary alone is insufficient.

Bürgermeister-Smidt-Brücke: different investigation tasks

On 21 April 2026, the Bremen Senate approved funding for preparatory investigations for the proposed replacement of the Bürgermeister-Smidt-Brücke. These included ordnance surveying in the river channel, cone penetration tests, boreholes and a foundation report. This Weser crossing between the city centre and Neustadt illustrates how different investigation tasks come together within a transport construction project. Their respective areas and results must be identifiable for further design; a geotechnical report does not also answer the ordnance question. The funding decision describes the proposed works, not their results or the investigation progress achieved later.

Working together

Assign tasks for the road construction phase

Client and operator

The developer describes the project and provides existing project documents. The operator adds requirements concerning use, access and scheduling. Those involved agree their respective tasks and decision-making responsibilities. Before commissioning, clearly record what information is missing, who will obtain it and which decision the result is intended to support.

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 investigation and documentation scope. Official requirements and decisions are clarified with the responsible authorities. The records needed for a specific procedure depend on the location and project. The technical report documents the specialist work performed, including areas, depths and limitations. Its applicability to further groundworks is checked against the specific intervention.

Bremen Police performs the tasks under Bremen’s Explosive Ordnance Act unless the Act provides otherwise. It defines the necessary surveying scope, maintains the register of suitable contractors and decides on clearance of the ground. Explosive ordnance is handled by the responsible authorities or contractors commissioned by them. Coordinate the proposed specialist works and responsible parties for the specific road construction phase.

Investigation task

Which specialist task comes next?

Relate existing findings to the trench drawing

Read official information and specialist reports with their accompanying maps. Compare the area investigated with the actual route and depths of the groundworks. A street name alone is insufficient. Identify outstanding crossings and installation positions before commissioning further works.

Assess historical documents

Account for utility lines and installations in technical planning

Street areas may contain utility lines, installations and metal structures. Coordinate method selection with the investigation objective and conditions. An area available under traffic regulations is therefore not automatically measurable without restriction. Technical planning specifies necessary preparatory works and remaining limitations.

Compare investigation methods
Project types

Define the actual intervention within the street

Illustration: two people with a tablet beside a drawing table and a survey trolley on a construction site.

Utility trench within a closed-off pavement

The area defined for traffic purposes may be larger than the planned trench. Draw its route, width and depth and the connection pits. Consider the investigation against this construction task. A traffic management drawing can support access planning but does not replace the intervention drawing. Compare changes within the same closure with existing findings before earthworks too.

When a trench is moved sideways, compare the new outer edges and connection pits with the existing investigation drawing. Include working spaces and planned widening at crossings. Keep it traceable which section has already been investigated at which position. An earlier traffic management drawing may still be needed while the technical intervention geometry has already changed. Site management brings the two revisions together and has additional investigation needs clarified before the new groundworks.

Specialist services and investigation tasks
Two people with a tablet beside a marked construction area; plans lie in the foreground.

New lighting or sign foundations

An individual foundation may lie beside a utility route already investigated. Identify its position, depth and required working space. Its small size does not mean a neighbouring report automatically covers it. If the construction design relocates it, relate the new point to the evidence again. The basis for the specific installation position then remains traceable.

Give each lighting or sign position a unique point number. Assign the planned foundation position and depth and its connections to the same drawing revision. Moving a post to the other side of the street requires comparison for its new volume of ground. Technical tasks may therefore change even if traffic routing remains unchanged. Results documentation identifies the points investigated and positions still outstanding.

Compare technical services for additional foundations
Illustration: two people review plans and documents at a table beside a construction vehicle.

Preparatory construction site access crossing

Creating access may require groundworks of its own. Describe their positions and execution in addition to the later main works. Bremen’s application procedure for the crossing and the ordnance question serve different purposes. Schedule the results needed before each intervention. Distinguish this from merely using existing traffic areas.

For a construction site access crossing, describe which areas will be opened during construction and which will merely carry vehicles during use. Identify existing paved surfaces, proposed removal and the positions of additional installations. Clarify the investigation scope needed for each distinct ground intervention. Bring together the necessary coordination under road law and technical prerequisites during construction preparation. If the access route changes, compare the intervention drawing and investigation results again before work starts.

Coordinate the sequence and tasks
Preparation

Prepare the scope and commission together

Establish what needs to be known before commissioning the work

First establish which decision the commission needs to support. Is the task an initial assessment of existing documents, an investigation of a specific area or examination of an anomaly that has already been assessed? These tasks require different evidence. A general wish for safety does not define an investigation that can be carried out. The enquiry therefore specifies the groundworks, location, depth and available findings. Suitable specialist work and the required reporting are then agreed on that basis.

Define the specialist task

Coordinate preparatory work with the investigation

Required access and survey conditions are clarified before the site visit. This may include keeping areas clear, obtaining service information and coordinating with other trades. The method and site determine which preparations are actually needed. Changes to the surface or additional groundworks are not undertaken unilaterally simply to prepare for a survey. Their sequence is agreed with the specialist designers and responsible parties.

Clarify preparatory work in the programme

Agree a clear scope and schedule

A reliable sequence distinguishes work whose technical prerequisites are already clarified from prerequisites still outstanding. If an area will be only partly accessible, account for this in the commission. Include results handover and assessment in the construction sequence too. Agree costs and dates against the described scope, access, records and execution conditions. Coordination considers when the next decision is needed for each construction phase.

Discuss the scope and schedule
Tasks at the site

Record trenches, foundations and access routes

01

Trench and connection positions

Show the trench route, width and depth. Include connection pits missing from the drawing. These details establish whether one continuous area or several separate areas belong to the investigation commission.

For a sewer section, reference the proposed excavation base and top edge to the same elevation system. Show gradients and varying trench depths in the longitudinal section. For a side connection, specify its actual connection point and the working space required.

02

Individual foundations

New foundations for signs, lighting or other installations need their own entry on the drawing. Check whether existing investigation results cover their position and planned depth. An investigated route beside the foundation does not answer this question.

03

Access to the construction site

Bremen provides a separate application procedure for constructing a site access crossing. For ordnance planning too, describe whether this will alter the ground and which area is affected. These works are not necessarily apparent from the proposed traffic arrangements.

Bremen’s online service specifies a recognised road construction contractor for creating a site access crossing. Coordinate this road construction prerequisite with the investigation needed for the volume of ground affected. Keep changed access positions traceable in both the application and technical planning.

04

Areas used temporarily

Will an area be used only for parking or storage, or must ground first be removed? Include earthworks on temporarily used areas in planning too. Whether and how they need investigation depends on their specific prerequisites.

If a temporary structure is proposed on an area used temporarily, identify its own ground interventions. These may include anchors, drainage or removal of existing paved surfaces. Coordination should distinguish where equipment will simply stand from where ground is to be moved. Keep this distinction current when site establishment changes.

Project documents

Documents that establish the next step

Use the same section names in all records

Use the same identifiers in the intervention drawing, investigation commission and results handover. Coordinate traffic arrangements and access accordingly. Investigation boundaries remain independently identifiable. A change of site management must not cause a completed section to be confused with an outstanding connection.

For longer utility sections, continuous chainage or clearly identified drawing sheets help locate the works. Record the actual position of a handover point between two contractors. The report, results plan and construction drawing must show which connection areas were considered. Hand over interrupted works with the investigation progress achieved. Before continuing later, check current conditions at the transition and agree the specialist works still needed.

Pass on different technical reports separately

Geotechnical, utility and ordnance records answer different questions. Assign each set of results to the specific works and hand them over to the design team together. Do not silently use one set of findings as a substitute for another. This also applies to a joint preparatory investigation programme for a transport structure. For the specialist ordnance task, bring together the commissioned measurement data, survey results and interpretation of findings with the full report and drawings. After clearance work, assign the clearance record, with its scope, results and remaining limitations, to the section actually worked.

Construction sequence

Coordinate investigation and construction sections

Before the first road construction phase

Assemble the intervention drawing, traffic plans and existing reports. Clarify access required and the progress of each procedure. The appropriate prerequisites must be in place for the first proposed groundworks. A general roadworks permit does not replace the necessary ordnance evidence.

Coordinate the construction phase with us

When moving to the next section

Hand over the report with the drawing of the area actually investigated. Compare additional crossings or relocated pits with existing findings before further work. Explicitly identify outstanding areas. The same traffic routing does not turn separate construction phases into a shared investigation result.

Coordinate the construction phase with us
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 assessment

Magnetometric survey

Geomagnetic methods record magnetic anomalies. Whether they can address the specific investigation task depends, among other factors, on expected objects, ground conditions, interference and the required investigation area. Fences, utility lines or existing structures can affect interpretation. A measurement signal is therefore not classified as explosive ordnance solely because of its strength. Plan the methods, interpretation and any further clarification as a coordinated technical task. Geomagnetic surveying measures the magnetic field passively. Detectability depends on the magnetic effect of the object sought.

Understand the scope of magnetometry

Electromagnetic methods

Electromagnetic investigations may suit particular metal target objects and site conditions. Justify suitability for the specific task rather than inferring it merely from available equipment. Account for interfering installations, accessible areas and the findings required. Document results with positions and investigation conditions. Whether another method is needed follows from technical assessment and remains a specific project decision. Transient electromagnetic methods, or TDEM, interpret the electromagnetic response of conductive objects over time. Assess suitability against the findings sought and measurement conditions.

Understand electromagnetic surveying

Ground-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 limitations

Deep-ground and downhole surveys

For deeper groundworks, it may be necessary to establish whether a surface investigation can provide the required findings or another approach is needed. Preparation includes the location, depth, borehole layout and existing services. Creating access for the investigation must also be properly planned by specialists. A general depth figure or standard grid cannot replace that work. Findings remain limited to the areas actually investigated and the method used.

Prepare deep interventions

Survey during construction

If a necessary preliminary investigation cannot be completed, the specialists assess whether a planned approach during construction is suitable. This includes coordinated investigation, interpretation and communication of findings within the intended work sequence. Visual observation of excavated material is not an interchangeable substitute for a necessary survey. Site management needs a clear description of when specialist work will take place, how new findings will be handled and which areas remain unresolved.

Agree the approach during construction
Technical assessment

Check existing records and measurement conditions

Drawings and earlier reports

Compare as-built drawings and earlier reports with the groundworks now proposed. A historical aerial photograph analysis and a technical investigation provide different findings. Record which investigation already exists and which question the new commission is to answer.

Review an older report with its complete map appendices. Identification requires the side of the street, section boundaries, depth datum and relevant ground surface at the time. Trace known changes if the street has since been rebuilt or a utility replaced. Technical assessment determines which findings still apply to the new trench and which details are missing. Where there are several partial reports, maintain a common overview drawing showing their areas and remaining gaps.

Utilities and installations

For surveying the measurement conditions on site must be assessed. Utility lines, installations and metal structures can affect the chosen method. Available equipment alone does not establish whether it suits the street area concerned.

Identify fixed and variable influences separately, such as existing utility lines, metal street furniture or temporarily parked vehicles. Record the conditions under which measurement data were collected. A connection investigated later may present different conditions from the first section. Account for these differences in the assessment. If a section remains inaccessible initially, document its position and agree the outstanding work needed for it before the next construction phase.

Relocated or deeper interventions

If a route is moved sideways or a pit deepened, compare the existing investigation scope with it again. The clearance plan or the investigation design must account for these changes. Even a relocation that makes sense for the construction sequence may lie outside the area already investigated.

Additional chambers or connection pits for changed drainage may affect a different volume of ground from the original utility trench. Provide the current geometry with depths and elevation datum. Define the technical task for this expanded volume. Changing traffic routing alone does not answer that question. The parties record which investigation is to be supplemented and which records are needed before additional earthworks.

Next steps

Coordinate groundworks from enquiry to results handover

01

Mark the working area on the drawing

Street names and house numbers help identify the location. For construction, site management also needs a drawing of the areas affected. Use the same section identifiers in the drawing, investigation commission and results documentation. At initial contact, identify the project, contact person and decision needed. Review existing information and complete earlier reports for currency, geographical relevance, scope and gaps. If additional historical findings are needed, we carry out the commissioned source research and aerial photograph analysis and relate them to today’s trench, foundation or access area.

02

Clarify access and records

Before the investigation date, clarify access to the area and which records remain missing. Coordinate traffic measures with the investigation date. A traffic management order does not replace necessary ordnance evidence. The investigation objective, expected objects, interference and access determine method selection. Before execution, clarify the scope permitted and required under Bremen’s rules with the responsible parties.

03

Perform the agreed investigation

Surveying or investigation during construction commissioned under Bremen’s requirements is carried out on the agreed areas and points. Measurement data and observations receive traceable positional and elevation references. Record areas not investigated, restricted access and relevant interference.

04

Assess survey data and findings

The collected data and findings are evaluated against the investigation objective. The technical assessment considers interference, the areas reached and remaining limits of the conclusions. It establishes which further investigation or work is needed for the planned groundworks.

05

Hand over results with an area drawing

Hand over the report with the drawing of the area investigated, method used and limitations identified. Site management must be able to identify which works the results cover. Connection areas not yet investigated remain explicitly outstanding. Document technical assessment, works performed and their limitations in the report and accompanying drawings. The agreed recipients receive the related records with a traceable revision.

06

Compare the next intervention with existing evidence

Before the next construction phase, compare the planned works with the relevant evidence. Identify relocated installation positions and additional crossings. Outstanding investigation needs can then be clarified before groundworks begin.

Documentation

Who grants clearance of the ground?

Findings and their scope

For construction measures on areas with suspected ordnance, section 5 of Bremen’s Explosive Ordnance Act describes commissioning a suitable contractor as further specified by the responsible authority. Starting the measures regulated there requires official clearance of the ground; the authority also decides on exceptions. The contractor’s report documents the specialist work performed; the authority decides on clearance of the ground.

Project responsibilities

Documentation includes the sections covered, their results and remaining limitations. Outside their federal scope, the BFR Ordnance Clearance guidelines provide technical guidance. Applicable Bremen requirements and official decisions are decisive for your project.

Working approach

How FONTANA-EOD works

Document the agreed specialist service clearly

We assess the planned groundworks against the available documents and their design revision. Before attending site, we agree with you what needs to be investigated, which areas are accessible and what findings are required. If the design or site conditions change, we check whether the agreed scope remains appropriate. The report states what was actually investigated and the limits of the findings. This allows designers and site management to see which findings they can use and where questions remain.

Discuss the investigation task

The task before the equipment

We first establish the investigation objective: which question must it answer? We then select a technically suitable method. The availability of a particular device or experience on a similar neighbouring site is not enough to justify the choice of method on its own.

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.

Understand the results

Use technical statements for the next decision

Bring traffic planning and investigation evidence together

Traffic measures organise the working area and use of adjoining areas. The ordnance report documents the specific technical work instead. Their boundaries may differ. Site management therefore needs the intervention drawing and corresponding results plan in addition to the traffic management drawing.

Understand investigation reports and their limitations

Identify relocations in good time

Moving a trench sideways may affect new areas of ground. Identify the change with its date and construction status. The technical planners compare it with earlier results. Additional requirements can then be defined for the areas actually affected before work takes place there.

Understand the service scope
Design and findings

Documents for the next construction decision

Illustration: aerial photographs and maps on two screens and printed on a desk.

Historical evidence and the current design

Aerial photograph interpretation is related to the actual groundworks. Its purpose and geographical scope remain distinct from a technical investigation of the ground as it is today.

Understand aerial photograph assessment
Illustration: two people review plans and documents at a table beside a construction vehicle.

Specialist reports for site management

The findings, their locations and limitations are handed over together. This makes clear to those carrying out the work which area has been investigated and which task remains outstanding.

Assess investigation reports
Four people in orange high-visibility vests in front of two excavators on a construction site.
Person with a yellow survey cart on a footpath in front of a hedge.
Questions from planning

Questions about groundworks in Bremen’s streets

Does a roadworks permit also cover explosive ordnance?

No. A traffic management order regulates the work site within the traffic area. Explosive ordnance must be addressed separately. Where official clearance of the ground is required under Bremen’s Explosive Ordnance Act, a traffic management order does not replace it.

Must the whole closed-off street be investigated?

The closure alone does not determine the investigation scope. The areas affected, proposed works, existing findings and official requirements are decisive. Show on the drawing where groundworks will take place and which areas are needed only for traffic or site establishment.

Can a trench be relocated within the closed-off area?

Before work at a changed position, check whether the existing investigation covers the new area and planned depth. A traffic closure provides no evidence of this. Technical planning may need adjustment and any outstanding investigation may need to be completed.

Which documents help the initial discussion?

Send a site plan showing intervention depths, the proposed construction sequence and existing ordnance records. Traffic management plans and records of existing conditions help coordination. Mark additional installation positions and changes so they can be included in the investigation commission.

What should happen if a suspicious object appears during roadworks?

Stop the affected work, do not touch or move the object, and move away from the location of the find. Keep others away and notify the police immediately on 110. Follow official instructions; do not investigate or transport the object yourself.

Must a lighting foundation beside a route be shown individually on the drawing?

Yes. Describe its position and planned depth and compare them with the documented investigation scope. Investigation of an adjoining route does not automatically cover this point.

Does the bridge funding decision prove investigations have been completed?

No. The Senate decision cited describes the preparatory tasks funded. It establishes neither results nor investigation progress achieved later. Other projects require their own records.

Which factors determine costs and the sequence of street works?

The route, width and depth of interventions, existing findings, installations and access are important. Traffic measures and construction phases may affect the sequence. Coordinate the technical task with these conditions. Methods, necessary preparatory works and documentation scope also matter. Under section 8 of Bremen’s Explosive Ordnance Act, the responsible party bears the costs of preparatory works, surveying, exposing objects and reinstatement; the state bears the costs of ordnance disposal as defined in the Act.

Project enquiry

Planning groundworks in Bremen City?

Show interventions on the street drawing

Send the trench route, crossings, foundations and preparatory access routes with their depths. Include traffic plans, as-built drawings and complete earlier reports. We discuss the specific technical task to be commissioned and missing information.

Explain the section and construction sequence

Identify the area needed first, proposed access and responsible contacts. Mark relocations from earlier drawings. Traffic and ordnance procedures remain separately traceable. Also state which earthworks are to start first and which areas are not yet accessible. Necessary preparatory works and results handover can then be coordinated in time.

GPR on a construction site
Project enquiry

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.

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