In this slip and fall case, Connie and Terry Pinckney appeal from the trial court’s grant of summary judgment to The Covington Athletic Club and Fitness Center (“Covington Athletic”). Because there is no genuine issue of material fact as to the existence of a defect and as to whether any such defect could have caused Connie Pinckney to fall, we affirm.
Summary judgment is proper when no genuine issue of material fact exists and the movant is entitled to judgment as a matter of law. OCGA§ 9-11-56 (c). Ade novo standard of review applies to an appeal from a grant of summary judgment, and we view the evidence, and all reasonable conclusions and inferences drawn from it, in the light most favorable to the nonmovant. Matjoulis v. Integon Gen. Ins. Corp., 226 Ga. App. 459 (1) (486 SE2d 684) (1997). So viewed, the record shows that Mrs. Pinckney fell at Covington Athletic as she stepped out of the swimming pool during a swim lesson. Pinckney testified in her deposition that “[a]s I was walking up the steps holding on the rail with my left hand, as soon as I put my right foot down on the deck to come up and stand on the last thing, it slipped.” Pinckney also testified in her deposition that on the day of her fall, she had no idea what made her fall, she saw nothing that could explain her fall, there was no substance on her foot after her fall, and she saw no “slime” on the day of her fall.
The accident report signed by Pinckney after her fall stated that the cause of the accident was “slipping on wet deck.” In her deposition, Pinckney acknowledged that the area where she fell was “sort of” wet. A Covington Athletic employee inspected the area after Pinckney’s fall and saw nothing other than water to explain her fall.
The day after Pinckney’s fall, Covington Athletic closed and drained the pool for replastering. When the pool reopened 12 days after Pinckney’s fall, she went back to the pool “because [she] was just wondering what was going on and why, how did I fall.” At that time, she “noticed that there was ... a little slime, greenish looking stuff that was along this line.” She then “assumed” that the slime was what *892caused her to fall 12 days earlier. Pinckney took a photograph of the area where she fell and testified that “a little” of the slime she observed was in the same place she placed her foot before her fall. The employee who inspected the area the day of Pinckney’s fall averred that he saw no algae or slime in the area of her fall at that time.
Based on this evidence, Covington Athletic moved for summary judgment and asserted that no genuine issue existed as to whether a defect was present at the time Pinckney fell and as to whether any such defect could have caused her fall. In response to the motion for summary judgment, Pinckney submitted an affidavit in which she claimed for the first time that before her fall, she “could feel that the wetness was not merely soaked with water but it had an abnormally slippery wet film, such as slime. I did not expect this.” The trial court applied the rule in Prophecy Corp. v. Charles Rossignol, Inc., 256 Ga. 27, 30 (2) (343 SE2d 680) (1986), to this new testimony and granted summary judgment in favor of Covington Athletic.
On appeal, Pinckney argues the trial court erred by applying the rule in Prophecy, supra, because her affidavit does not contradict her deposition testimony and because she provided a reasonable explanation for her “additional testimony.” We disagree.
Pinckney’s affidavit clearly contradicts her earlier testimony that she “had no idea what made her fall,” and just “assumed” that it was algae based on what she saw 12 days later. Unless she offers a “reasonable explanation” for this contradiction, the statement in her affidavit cannot be considered. Prophecy, supra. “The burden rests upon the party giving the contradictory testimony to offer a reasonable explanation, and whether this has been done is an issue of law for the trial judge.” (Citations omitted.) Id.
Here, Pinckney attempts to explain the inconsistency by claiming that she “never had the opportunity to explain this fully when [her] deposition was taken.” But the multiple questions posed in her deposition provided Pinckney ample opportunity to explain what she observed before she fell, including any “slime” or abnormal slipperiness. Additionally, the transcript of Pinckney’s deposition shows that although she reserved the right to read and sign her deposition, she did not make any changes or additions to her testimony on the errata sheet provided to her by the court reporter as permitted by OCGA § 9-11-30 (e). See J. H. Harvey Co. v. Reddick, 240 Ga. App. 466, 473 (2) (522 SE2d 749) (1999) (changes to form or substance expressly contemplated by OCGA § 9-11-30 (e)). Because Pinckney had an opportunity to explain fully her testimony both in her deposition and on the deposition errata sheet provided by the court reporter but failed to do so, this court concludes that her explanation, that she had no such opportunity, is unreasonable.
*893When Pinckney’s contradictory averments in her affidavit are removed from consideration, the remaining evidence — Pinckney’s claim that she slipped on a wet pool deck while climbing out of the pool — fails to create a genuine issue. The standing water in plain view on the pool deck was a hazard “any person with ordinary, common sense would recognize as something that might cause a person to trip, slip, or fall.” (Citation and footnote omitted.) Music v. Steamco, Inc., 265 Ga. App. 185, 186 (593 SE2d 370) (2004); see also Brownlow v. Six Flags Over Ga., 172 Ga. App. 242, 243-244 (322 SE2d 548) (1984) (appellant failed to exercise ordinary care for her own safety where she was aware of wet conditions caused by patrons exiting a water ride).
A photograph taken 12 days after Pinckney’s fall does not create a genuine issue about the existence of algae at the time she fell, particularly when the pool had been closed for repairs during the intervening period. The employee who inspected the area after Pinckney’s fall saw nothing other than water to explain her fall, and this evidence is consistent with Pinckney’s deposition testimony that she had no idea what caused her to fall and saw nothing that could have explained her fall.
“The threshold point of inquiry in a slip and fall case is the existence of a hazardous condition on the premises. Proof of a fall, without more, does not create liability on the part of a proprietor or landowner. It is common knowledge that people fall on the best of sidewalks and floors.” (Citations and punctuation omitted.) Flag star Enterprises v. Burch, 267 Ga. App. 856, 856-857 (600 SE2d 834) (2004). Additionally,
[cjausation is always an essential element in slip or trip and fall cases. Where the plaintiff does not know of a cause or cannot prove the cause, there can be no recovery because an essential element of negligence cannot be proven. A mere possibility of causation is not enough and when the matter remains one of pure speculation or conjecture ... , it is appropriate for the court to grant summary judgment to the defendant.
(Citations and footnotes omitted.) Pennington v. WJL, Inc., 263 Ga. App. 758, 760 (1) (589 SE2d 259) (2003).
This is a case in which only speculation and conjecture support the conclusion that algae was actually present at the time of Pinckney’s fall. Moreover, even if we were to assume a genuine issue with regard to the existence of a hazard, speculation and conjecture are also the only support for the conclusion that algae caused Pinckney to fall. See Pennington, supra, 263 Ga. App. at 761 (2) (summary *894judgment granted to defendant because only causation evidence was presence of hoses at scene and “speculation after the fact” that plaintiff must have tripped over hoses); Moore v. Teague, 255 Ga. App. 220 (564 SE2d 817) (2002) (affirming grant of summary judgment to defendant where plaintiff “assumed” she slipped on wet floor, but testified that she did not know if floor was actually wet and did not know why she slipped); Shadburn v. Whitlow, 243 Ga. App. 555 (533 SE2d 765) (2000) (defendant entitled to summary judgment where witnesses “believed” woman fell on loose carpeting at top of stairwell, but also admitted that they were not certain what caused fall).
Because the evidence fails to create a genuine issue with regard to both the existence of algae at the time of Pinckney’s fall and whether any such defect could have caused her fall, the trial court properly granted summary judgment in favor of Covington Athletic.
Judgment affirmed.
Andrews, P. J., Johnson, P. J., Ellington and Adams, JJ., concur. Barnes, C. J., and Miller, J., dissent.