You're right, this is a funny one! Bonding those trench drain grates... welcome to the wonderful world of pool bonding and its sometimes absurd applications of code interpretation.Here's the breakdown, and why your question is valid, plus the likely answer and how to approach it

The Code Basis (Simplified)
NEC 680.26(B): Bonding. This section mandates the bonding of various metal parts associated with swimming pools. The goal is to create an equipotential plane around the pool to minimize voltage gradients in the pool area, thus reducing the risk of electric shock. NEC 680.26(B)(7): Other Metal Parts. This is the kicker. It says: "Other metal parts, including metal conduit and piping, metal cable sheaths, metal surface trim, metal drain fittings, and metal parts of electrical equipment that are not likely to become energized but are located within 5 ft (1.5 m) horizontally of the inside walls of the pool...shall be bonded."Why This is Funny

It's a trench drain! It's literally designed to take water away from the pool! The chance of it becoming energized and causing a shock is minuscule. Bonding every individual grate section seems ridiculously overkill.

The Likely Interpretation & What Inspectors Will Want

Despite the absurdity, you're likely right – you'll probably have to bond the grate sections. Here's why:

"Metal Parts within 5 ft"

The grate sits within that 5ft radius.

Risk Aversion

Inspectors often err on the side of caution when it comes to pool safety.

Interconnected Metal

The individual sections are touching each other, forming a longer, more connected metallic object.

Is it a Listed Assembly? NO!!

NEC 680.26(C) talks about Listed Bonding Assemblies, but that is a different section. This section is about bonding the rest of the pool, not your trench drain cover.

How to Bond the Grates (Practical Considerations)

This is where you need to be clever and think about longevity in a wet/corrosive environment.1.

Your #8 AWG Copper Conductor (Perfect)

Use a solid or stranded (preferably stranded) #8 AWG copper conductor (insulated or bare - check your local code). Bare would be more appropriate for the underground application.2.

Your Options for Connecting

This is where you need to balance electrical integrity with practicality and corrosion resistance.

Through-Bolting

This is probably the most reliable long-term.

Procedure

1. Drill a hole through the side of each grate section. You want it to be on the vertical so you can bond each one.
2. Use stainless steel bolts, nuts, and washers (critical for corrosion resistance).3. Sand or grind away any coating at the contact point on the grate.
4. Crimp your #8 to ring terminals, use dielectric grease between the surfaces of the grate and the ring terminals and then through bolt each one of your sections.5. Torque the bolts to ensure good electrical contact.

Drill and Tap

Same basic idea as through-bolting. Tapping the hole allows you to use a stainless steel machine screw. Again, ensure good metal-to-metal contact and use anti-seize/corrosion inhibitors.3.

Continuous Run (Key)

Run the #8 solid or stranded copper bonding conductor continuously along the entire length of the trench drain. Do not make breaks and separate connections. Each grate section should be connected to the same, continuous conductor.4.

How Many Connection Points

You would need to connect at a minimum every grate section.

Important Considerations and Recommendations



Electrical Inspector Pre-Approval

Talk to your local electrical inspector before you start. Explain your plan and get their blessing. This can save you headaches and rework later. They may have a preferred method.

Documentation

Take pictures of your bonding process before you backfill or cover anything. This will be invaluable if there are questions later.

Corrosion Prevention

This is essential. Use a liberal amount of dielectric grease at all connections to prevent corrosion between dissimilar metals. Stainless steel hardware helps, but the copper conductor can still corrode.*

Access

Consider if you need any access points to check the continuity of the bonding conductor in the future. It's unlikely you'll need it, but it's a good thought.

In summary:

Bonding the grates is likely overkill, but you will probably have to do it. Talk to your inspector, use a continuous #8 conductor, and focus on creating reliable, corrosion-resistant connections. Through-bolting with stainless steel hardware and dielectric grease is probably your best bet. Good luck! You'll get through this and can laugh about it later. Flag for review