La charge de travail est trop lourde aujourd'hui.

Because charge is a feminine singular noun, and the adjective has to agree with it.

• le travail = masculine singular
• la charge = feminine singular
• so: lourd → lourde

Here, lourde describes charge, not travail.

Charge de travail means workload.

Literally, it is something like load of work:

• charge = load, burden
• de travail = of work

So the full expression is a standard French way to say workload.

French often uses noun + de + noun where English might use a compound noun.

So:

• charge de travail = load of work = workload
• salle de classe = room of class = classroom
• verre d'eau = glass of water

Here, de links charge and travail.

French usually uses an article more often than English does.

So even when English says just workload, French often says:

• la charge de travail

In this sentence, it refers to a specific workload, probably the one relevant today.

This is an important difference:

• très lourde = very heavy
• trop lourde = too heavy

So trop means there is more than is acceptable, comfortable, or manageable.

In this sentence, trop lourde suggests the workload is excessive, not just large.

No. Just like English heavy, French lourd / lourde can be used both:

• literally: a physically heavy object
• figuratively: something burdensome, intense, or hard to handle

So a charge de travail lourde is a heavy workload, not something physically heavy.

Because the sentence is describing a state or quality of the workload.

• est = is
• It comes from être

So:

• La charge de travail est trop lourde = The workload is too heavy

French uses être with adjectives in the same basic way English uses to be.

Yes, and that is often a very natural alternative.

Compare:

• La charge de travail est trop lourde aujourd'hui.
  = The workload is too heavy today.
• J'ai trop de travail aujourd'hui.
  = I have too much work today.

The first sounds a bit more formal or objective.
The second sounds more personal and conversational.

Putting aujourd'hui at the end is very natural in French.

This placement makes the sentence flow well:

• La charge de travail est trop lourde aujourd'hui.

You can also move it for emphasis:

• Aujourd'hui, la charge de travail est trop lourde.

Both are correct, but the original version is very normal and neutral.

A rough English-style approximation is:

• oh-zhoor-dwee

A more precise pronunciation is:

• /o.ʒuʁ.dɥi/

A few points:

• the j sounds like the s in measure
• the r is the French r
• the hui part is not pronounced like English hoo-ee; it is more compact

Also, the h in aujourd'hui is silent.

Because historically the expression comes from older forms meaning something like on the day of today.

In modern French, you should simply learn aujourd'hui as one fixed word meaning today.

The apostrophe is just part of the spelling. It does not mean you should pause.

Yes.

Singular:

• la charge de travail = the workload

Plural:

• les charges de travail = the workloads / workloads in general

And the adjective would agree too:

• Les charges de travail sont trop lourdes.

Notice:

• charges gets -s
• lourdes also gets -s because it agrees with a feminine plural noun

It sounds mostly neutral.

It is perfectly normal French, and it works well in:

• conversation
• workplace discussion
• writing
• emails

If you want something more casual, a speaker might say:

• J'ai trop de boulot aujourd'hui.

Here, boulot is a more informal word for work.