Can the pitch be watered during a match, and how are footholes and creases maintained?

Watering: the pitch must not be watered during the match (Law 9.4).

Re-marking creases: creases are re-marked whenever either umpire considers it necessary (Law 9.5).

Footholes (Law 9.6):

• The umpires make sure holes made by bowlers and batters are cleaned out and dried whenever needed to keep play going.
• In matches of more than one day, the umpires allow, if necessary, re-turfing of the bowlers' footholes in their delivery strides, or the use of quick-setting fillings.

Securing footholds (Law 9.7): during play, players may use sawdust to secure their footholds, as long as it doesn't damage the pitch and isn't unfair play.

Non-turf pitches (Law 9.8): all the rolling, sweeping, mowing, watering, crease and foothole rules apply wherever appropriate.