Rats Coming from the Street or the Neighbouring Plot: Your Options

"I haven't changed a thing at home, and for the past three weeks I've been seeing them cross the terrace in the evening." This kind of call has become common in the Val-de-Marne, and the explanation is almost always the same: the rats aren't coming from your house, they're coming from next door. A plot left derelict for two years, a building site that has opened up the sewers, a neighbouring house where bags of birdseed and cat bowls pile up, a communal bin store whose door no longer closes, a bank of the Marne where burrows are multiplying.

In this situation, treating only your own property is like bailing out a boat without plugging the leak. You can set out every bait station in the world in your garden: if the colony lives twenty metres away, on the other side of the fence, with unlimited food and shelter, it will rebuild itself indefinitely. So two things have to happen in parallel: make your property impenetrable and get the source dealt with — which means knowing who is responsible, who to call, and what the law allows you to demand.

This guide sets out the steps, in order, for a private owner or tenant of a house in the 94 département.

First step: prove the source is outside your property

Before writing to anyone, you need evidence. A letter saying "there are rats in the neighbourhood" triggers nothing. A letter saying "active runs along the party wall on the plot 112 side, three burrows at the foot of the hedge, time-stamped photos from 5 and 9 October" triggers a site visit.

What you're looking for are signs of movement, not the rats themselves (they're rarely seen):

• Runs: strips of compacted, shiny earth, 5 to 8 cm wide, along walls, fences and kerbs. Brown rats are thigmotactic — they hug obstacles.
• Burrows: holes 6 to 10 cm in diameter, often under a log pile, a loose paving slab, a tree stump or a compost bin. An active burrow has a clean entrance, with no cobwebs or dead leaves.
• Droppings: spindle-shaped, 15 to 20 mm, black and glossy when fresh, grey and crumbly after a few days.
• Signs of passage under fencing: digging beneath the wire mesh, a hole in a hedge, a gap under a gate.
• Gnawing marks: chewed-open bags of pet food, the bottom of the shed door, a garden hose.

Document everything: dated photos, a sketch of the plot marking where the signs are, a log of observations (date, time, place). A motion-detection camera of the trail-camera type, set facing the fence, settles the question of which way the rats are travelling within two nights — and that is the piece of evidence that tips a case with a town hall or an insurer. A red-light torch is the other useful accessory: rodents are barely sensitive to it, so you can watch without scaring them off.

Simple rule of thumb: if the densest signs are around the edges of your plot, on the neighbour's side or the street side, and they fade as you move towards the house, the population lives outside and merely visits you. If it's the other way round, the harbourage is on your property — and the approach is different.

Who is responsible? What the law actually says

This is the most widely misunderstood question. France has no general "duty to control rats on your own land" that can be invoked against just any neighbour. But three levers do exist, and they are solid.

1. The departmental sanitary regulations (RSD)

The departmental sanitary regulations, still in force for those provisions not absorbed into the Public Health Code, require owners and occupiers to maintain premises and land, to control rodents and insects, and to remove waste regularly. They prohibit the accumulation of rubbish and objects liable to harbour vermin. This is the basis on which the mayor most often acts.

2. The mayor's policing powers

The General Local Authorities Code (articles L.2212-1 et seq.) gives the mayor municipal policing powers, including over public health and sanitation. An abandoned plot that has become a rat harbourage, illegal dumping, a hoarded dwelling spreading infestation: the mayor can serve formal notice on the owner to carry out works, then have them carried out directly at the owner's expense. The Public Health Code (article L.1311-4) also allows the prefect or the mayor to order urgent measures to end a specific health hazard.

3. Abnormal neighbourhood nuisance

On the civil side, the settled case law on abnormal neighbourhood nuisance — now codified in article 1253 of the Civil Code since the Act of 15 April 2024 — allows you to obtain compensation and an order to stop the nuisance without having to prove fault. A rodent infestation sustained by the state of a neighbouring plot typically falls within this framework. Keep this route for last, if dialogue and the town hall lead nowhere.

And if the neighbour is a social landlord or a utility network operator?

The same logic applies: the owner or manager of the land answers for its condition. For sewerage networks, responsibility lies with the local authority or the managing board; for a road, with the highway authority; for an SNCF parcel or a building site, with the project owner. In every case, going through your town's municipal hygiene and health service (service communal d'hygiène et de santé, SCHS) is the most effective shortcut: they know who to approach.

The process, step by step

1. Talk to the neighbour (and keep a record)

In 60% of cases involving a private house, the cause is mundane and unintentional: an overloaded bird feeder, a split bag of chicken feed, an open compost bin fed with meat scraps, cat bowls left outside overnight, a log pile sitting directly on the ground for three years. Many neighbours have no idea of the connection. A factual conversation, with your photos, often settles the matter.

If the discussion gets nowhere, send a standard letter and then a registered letter describing your observations, the dates, and what you are asking for. This is the document on which everything else rests.

2. Contact the town hall and the hygiene service

In the Val-de-Marne, several towns have a municipal hygiene and health service or a public-health unit: this is the case in Champigny-sur-Marne, Créteil, Vitry-sur-Seine, Saint-Maur-des-Fossés, Nogent-sur-Marne, Fresnes, Villiers-sur-Marne and Sucy-en-Brie, among others, under various names. Send a written report (online form or letter to the mayor) including:

• your name and address;
• the address or land-registry reference of the suspected plot;
• a description of your observations, with dates;
• the photos;
• a reminder that you are requesting a site visit under the departmental sanitary regulations.

Many towns also run rat control campaigns on public land and sewer networks, once or several times a year — the operation carried out in central Charenton in spring 2026 and the repeated interventions in the Bois-l'Abbé district of Champigny are cases in point. These campaigns treat the sewerage network, green spaces and the surrounds of apartment blocks: they do not treat the interior of private properties. It is worth asking to be told the schedule: treating your own property a few days before the municipal round is counterproductive, whereas the reverse is far more effective.

3. If there is a health hazard: the ARS

The Île-de-France regional health agency (Agence régionale de santé) steps in when the situation goes beyond mere nuisance: unfit housing, risk of disease transmission, bites. Remember that rodents are reservoirs of leptospirosis — a disease closely monitored by Santé publique France, the risk of which rises with contact with contaminated water, typically after the Marne floods. In the event of a bite or a contaminated wound, seeing a doctor the same day is non-negotiable.

Who pays for what?

Two useful clarifications. First, the town hall does not provide free rat control on private property: municipal campaigns stop at the boundary of public land, barring a specific local scheme. Second, a quote for external treatment of a house generally falls in the €150 to €400 range for an initial intervention with secured bait stations and follow-up, more if proofing works are needed — our detailed benchmarks are on the pricing page.

In the meantime: make your plot inhospitable

Processing a case takes weeks. You, however, need results right away. Three jobs, in order of real effectiveness.

Cut off the food

This is lever number one, by a wide margin. A brown rat needs 25 to 30 g of food a day. Remove it and the population can no longer grow on site.

• Pet food and seed: never an open bag in the shed again. A sealed metal storage bin closes the matter — soft plastic is gnawed through in a single night.
• Compost bin: never meat, fish, dairy or cooked leftovers. A closed compost bin with a mesh base prevents digging from underneath; an open bin on bare soil is a heated larder.
• Chicken coop: feed in the morning, remove at night, store the grain indoors in a metal container.
• Bird feeders: at ground level, it's an open buffet. A suspended tray with a seed catcher is acceptable.
• Fruit trees: pick up fallen fruit. In October, the windfall apples in a Saint-Maur garden feed more rodents than a bin does.

Cut off the shelter

• Clear a 30 cm strip of ground around the walls: no wood stacked against the façade, no tarpaulins, no pallets.
• Raise the log pile onto an open metal support.
• Cut back tall grass and brambles along the plot boundary, at least a metre-wide strip.
• Clear out the corners: tyres, rubble, broken garden furniture. Each one is a potential burrow site.

Seal access to the building

A rat gets through a 2 cm opening, a young brown rat through even less. At this stage you need to inspect the house crouched down, torch in hand.

• Bottoms of garage and shed doors: a metal threshold strip or door sweep.
• Low-level air bricks, crawl-space vents, roof vents: stainless steel mesh with a 6 mm aperture, screwed in place, not stapled. Thin galvanised mesh gets gnawed or rusts.
• Conduit entries and service penetrations: packed steel wool followed by sealing mortar. Polyurethane foam on its own doesn't last a fortnight.
• Garage or cellar floor gullies: a screwed-down grate, and for a suspect waste stack, a non-return valve fitted by a plumber.

A fine stainless steel mesh kit and a few tubes of repair mortar will do more for your peace of mind than three boxes of bait.

Baiting yourself: what the regulations allow

Anticoagulant rodenticides sold to the public are biocidal products governed by European Regulation 528/2012, with ANSES handling authorisations in France. A few non-negotiable rules for a private individual:

• Baits must be placed in a secured bait station, inaccessible to children, pets and wildlife. A sachet tucked behind a flowerpot is both illegal and dangerous.
• No permanent open-air baiting without good reason: authorisations restrict outdoor use, duration and quantities. Read the label — it has regulatory force.
• Never on land that isn't yours. Baiting on the neighbour's property or on waste ground, even with the best intentions, leaves you exposed — and will be used against you if an animal is poisoned.
• Anticoagulants cause secondary poisoning in birds of prey, hedgehogs, cats and dogs. That is the main argument for doing without them outdoors and favouring mechanical traps.
• Snap traps for rats placed inside closed housings are a clean and controllable alternative, to be checked every morning. Have disposable protective gloves ready for handling and removing carcasses.

Cholecalciferol-based baits and mechanical traps are today the most defensible options for a suburban garden where pets roam. Our equipment selections can be found in the shop.

When to call a professional

The threshold is fairly clear. One or two individuals spotted, signs confined to the perimeter, no active burrow: your exclusion and clean-up measures will generally be enough within two to three weeks. Beyond that, going it alone reaches its limit.

Call when:

• you see rats during the day — a sign of a dense population spilling out of its territory;
• there are active burrows and several distinct runs;
• the rodents have got into the building: loft, crawl space, cellar, partition walls;
• the source is third-party land and you need a written diagnostic report for the town hall, the landlord or the insurer;
• there has been a bite, or rodents have been present near a baby or a vulnerable person;
• your neighbourhood has just come through flooding or works on the sewer network.

A professional brings three things you can't buy at a garden centre: a diagnosis of infestation pressure and movement patterns, access to products and devices for professional use, and a document that carries weight. That last point is often the real reason to call: it is what gets a reluctant neighbour or an overstretched hygiene service to move.

Our rat control work covers diagnosis, installation of secured bait stations, proofing recommendations and follow-up, across all the towns listed in our service areas. If the situation is critical — a rat indoors, a bite, a nest in a child's bedroom — go straight to the emergency page.

Key takeaways

• Rats crossing your garden almost always come from a harbourage outside it: identify it before treating.
• Document everything: dated photos, a log, the location of the signs. Without evidence, no procedure moves forward.
• The departmental sanitary regulations and the mayor's policing powers can be used to compel a negligent owner; abnormal neighbourhood nuisance (article 1253 of the Civil Code) remains the final remedy.
• The town hall treats public land and the sewer network, not your property.
• Food and shelter first, proofing the building next, baits last and always in a secured station.

For an on-site diagnosis and a written report you can use with your town hall or your insurer, contact us: we work throughout the Val-de-Marne.