Lincolnshire Drainage Solutions guides

Guide to Property Selling with Septic Systems

Selling a property can be a naturally stressful process, and unexpected issues can make it even more challenging. Last-minute glitches or concerns raised by potential buyers can lead to delays, price negotiations, or even jeopardise the entire sale.

One often underestimated factor that can add tension to property transactions is the presence of septic tanks and other off-mains drainage systems such as sewage treatment plants or cesspits. This issue is compounded by a couple of reasons. Firstly, these systems are hidden underground, shrouded in mystery, and their actual condition is often uncertain, making them a potential source of uncertainty in a smooth property sale. Secondly, the high cost associated with repairing or replacing these systems can make them appear as potential liabilities in the eyes of prospective buyers.

Dealing with these concerns can be a challenge, and it’s essential to address them effectively to ensure a successful property transaction.

1. Responsibilities When Selling a Property with a Septic Tank

When selling a property with a septic tank, certain responsibilities are in place, mandated by current legislation and advised to facilitate a smoother sales process. Let’s begin by outlining the key areas where compliance is essential:

a. Disclosure of the Existing Drainage System:

As per the General Binding Rules for Small Sewage Discharge, it’s crucial to inform the new property owner in writing about the presence of a sewage discharge system if your property relies on off-mains drainage. This disclosure should cover:

  • A comprehensive description of the treatment plant and drainage system.
  • Clarity on the main components’ locations, including the treatment plant, drainage system, and discharge point (whether it discharges to the ground, a nearby watercourse, or ditch).
  • Documentation of any alterations made to the treatment plant and drainage system.
  • Maintenance instructions for the treatment plant, along with the maintenance manual if available.
  • Records of maintenance activities, if maintained.

It’s worth noting that routine septic tank emptying is essential and can provide reassurance to potential buyers. While retaining receipts for routine emptying can be beneficial, it’s not a mandatory requirement for septic tank owners. As an alternative, collecting information on past emptying dates, especially from a consistent tank-emptying service provider, can also serve as evidence.

b. Avoiding Watercourse Discharge:

If your property features a septic tank discharging wastewater directly into a ditch or watercourse, it’s imperative to address this issue. The General Binding Rules specify that such systems must either be upgraded or replaced by January 1, 2020. This aligns with environmental safety concerns, recognising that discharging septic tank effluent into watercourses is no longer considered environmentally responsible.

The rules explicitly state that for properties with septic tanks discharging into surface water and sold before January 1, 2020, the responsibility for replacing or upgrading the existing treatment system should be part of the sale agreement between the buyer and seller. (For comprehensive guidance, please refer to:

Although there is currently limited guidance available regarding property sales after January 1, 2020, particularly due to the limited awareness among property owners about these changes, it is prudent to anticipate the continued application of these rules. The overarching objective of these rules is to mitigate environ.

2. Evaluating Your Property’s Drainage System

When it comes to assessing your drainage system’s condition and specifics to convey crucial information to potential property buyers, you need a comprehensive approach. A standard building survey, usually conducted for prospective buyers, often offers only a superficial examination of off-mains drainage systems. These reports typically recommend that the buyer arranges a specialised drainage survey for a more thorough analysis, and this is where potential complications can arise.

Focusing specifically on septic tanks, these surveys can uncover issues related to compliance and the overall condition of the drainage system, which can become hurdles during a property sale.

As the property seller, it’s vital to take a proactive approach to protect your interests and the environment, especially if your drainage system no longer complies with the latest regulations. We strongly advise seeking the expertise of a specialist to conduct a comprehensive survey of your drainage system. The resulting report can be a valuable asset if necessary or presented to potential property buyers. This comprehensive report should include:

  • An illustrated plan of the drainage system, outlining its layout.
  • Identification of the type of tank in use.
  • The known discharge point of the system.
  • A thorough assessment of the drainage system’s condition, including an evaluation of the tank’s structural integrity and the condition of accessible pipework. The tank should be emptied during the survey to observe how the system responds to this process. The return of wastewater to the tank from the soakaway system can provide insights into its functionality.
  • Guidance on whether the system complies with relevant regulations.
  • A concise summary of any necessary remedial actions and estimated costs.

3. Ensuring a Smooth Property Sale with a Septic Tank

In essence, when you’re in the process of selling a property with a septic tank, the key lies in providing prospective buyers with transparent information about your drainage system’s type, compliance with regulations, and its current condition. Demonstrating proper maintenance of the system can also be highly advantageous. The journey of gathering this essential information can never start too early.

If you find yourself uncertain about where to begin or require assistance, we stand ready to help. Our home seller drainage survey service ( is designed to streamline your property sale, optimise your sale price, and ensure compliance with septic tank regulations.

For inquiries or to schedule your survey, reach out to our dedicated team at 07902 688279. We’re here to address any questions and get your survey arranged promptly, making the selling process as smooth as possible for you.