On the set, Joanne Woodward told the then seventeen-year-old Melanie Griffith, who was playing her daughter, that she had three goals in life: Marry a movie star (Paul Newman), have beautiful babies (she had three), and win an Oscar (which she did in 1958). Melanie said that she adopted those goals for herself by marrying a movie star (Antonio Banderas), having beautiful babies (she also has three), but expressed frustration that she hasn't won an Oscar, even though she was nominated in 1989 for the Best Actress Academy Award for Working Girl (1988).

According to the biography "Paul Newman: A Life" (2009) by Shawn Levy, Newman had an almost major accident whilst racing a Porsche car at a New Orleans race-track off set during production. According to the book, Newman and a cohort were not wearing seat belts when the vehicle spun out of control. Newman said: "For a time we rode on two wheels. Then the car went on its side but we weren't thrown out. The windshield shattered. Fortunately it was European glass that breaks into powder on impact. We climbed out of the windshield. Neither of us was hurt. We hardly had our hair mussed. As I stood by the car, somebody slammed the door on my hand. Fortunately the door was sprung or I would have lost the tips of my fingers. 'Open the door' I said quietly. When they did, I ran to the beer cooler and stuck my fingers in the icy water. I didn't even lose my fingernails." Incidentally, in the earlier Lew Harper movie Harper (1966) starring Newman, the make and model of Lew Harper (Paul Newman)'s car was also a Porsche, a black-top gray / silver Porsche 356 A Speedster.

The Lew Harper character was originally known as Lew Archer in the series of detective novels. According to Frank Miller at the TCMDb, for the first Paul Newman Lew Harper movie Harper (1966), the success of source novelist Ross Macdonald's Lew Archer detective series "didn't stop [actor Paul] Newman from changing the name of Macdonald's most famous detective, however. Struck by his success in two films beginning with the letter "h" - The Hustler (1961) (1961) and Hud (1963) (1963), Newman asked that the private eye's name be changed from Archer to Harper". However, alternatively, Wikipedia states "The name of the lead character was changed from Lew Archer to [Lew] Harper because the producers had not bought the rights to the series, just to 'The Moving Target'. [Screenwriter William] Goldman later wrote 'so we needed a different name and Harper seemed OK, the guy harps on things, it's essentially what he does for a living'."

The studio sound-stage that was used to house "the Drowning Pool" was Stage 15 at the Warner Brothers Burbank Studios. The stage had been a studio watering place for such earlier pictures as the marlin fishing scenes in The Old Man and the Sea (1958) and the Arctic ice floe sequence in The Great Race (1965).

During post-production, director Stuart Rosenberg hired Composer Charles Fox to do additional scoring, integrating the composer's melody "Killing Me Softly With His Song", into the movie. The song had been a #1 hit two yrs prior, while Fox was scoring Rosenberg's previous film, "The Laughing Policeman"

The amount of water that 'the drowning pool' hydro-therapy chamber contained was 37,500 gallons.

The Drowning Pool marked a reteaming of Paul Newman, Joanne Woodward, and Anthony Franciosa. All of whom appeared in The Long, Hot Summer.

The picture was not the commercial success at the box-office that its precursor Harper (1966) had been.

Lew Harper (Paul Newman)'s fee was $150 per day plus expenses which had increased by $50 from his fee in the first film Harper (1966).

Actor Paul Newman once said of the Lew Harper character in the "Paul Newman: A Life" (2009) biography by Shawn Levy: "I simply adore that character because it will accommodate any kind of actor's invention...It's just lovely to get up in the morning, it's great to go to work, because you know you're going to have a lot of fun that day".

The eighth cinema movie collaboration of husband-and-wife actors Paul Newman and Joanne Woodward.

Robert Mulligan was originally signed to direct.

Paul Newman would reteam with Melanie Griffith in Nobody's Fool wherein she played his potential love interest.

Actress Melanie Griffith was aged only about seventeen.

The New Orleans location was the same setting that actors Paul Newman and Joanne Woodward's previous film WUSA (1970) had.

The film's source Ross Macdonald 1950 novel of the same name was set in Southern California but the setting was moved to New Orleans for this filmed version.

Fourth and final feature film collaboration of actor Paul Newman and director Stuart Rosenberg. The movies are WUSA (1970), Pocket Money (1972), Cool Hand Luke (1967), and The Drowning Pool (1975).

One of two 1975 "film noir" pictures featuring Melanie Griffith, a then very young actress. The other movie was Arthur Penn's Night Moves (1975).

In a scene concerning Paul Newman and Andy Robinson, armed men are wearing masks very similar to ones worn by Robinson and his partner in another Neo Noir, Charley Varrick.

The movie's lead stars Paul Newman and Joanne Woodward were married.

The film was made and released about twenty-five years after its source novel of the same name by Ross Macdonald had been first published in 1950.

'The Drowning Pool' set was built within an inner tank which measured 13 x 18 x 10 feet deep. This inner set resided within an outer permanent tank that measured 21 x 25 x 12 feet deep.

After Harper (1966), this is the second and final "Lew Harper" film.

According to trade paper Variety, the Drowning Pool "title derives from an offbeat and exciting climactic sequence in an abandoned mental asylum hydro-therapy room".

The cost to construct the "drowning pool" hydro-therapy chamber set was $60,000.

Star Billing: Paul Newman (1st), Joanne Woodward (2nd), and Anthony Franciosa (3rd).

Average Shot Length = ~7.2 seconds. Median Shot Length = ~7.3 seconds.

According to Allmovie, "This was Coral Brownes first film after her marriage to actor Vincent Price in 1974".

This sequel was made and released around nine years after its precursor Harper (1966) had debuted in 1966.

The movie and its precursor Harper (1966) both had a connection to Alfred Hitchcock. The earlier movie co-starred Janet Leigh who had starred in Psycho (1960) whereas this picture co-starred Melanie Griffith who was the daughter of Tippi Hedren who co-starred in The Birds (1963). Well... and Paul Newman starred in Hitchcock's Torn Curtain, so....

Paul Newman: [H] The character Lew Harper is based on novelist Ross Macdonald's character Lew Archer. The name was changed for the first 'Lew Harper' film Harper (1966) supposedly because Paul Newman had recently enjoyed success with Hud (1963) and The Hustler (1961) (two of his successful films beginning with the letter "H", a later one after Harper (1966) was 1967's Hombre (1967)) and the producers wanted the movie's title to begin with "H". Also, the Macdonald estate did not want the name "Archer" used in the movie. There may have been fear of legal complications because Macdonald got the name "Archer" in the first place from Miles Archer, Sam Spade's partner who is killed early on in Dashiell Hammett's The Maltese Falcon (1941)".