San Francisco Baykeeper v. Sunnyvale

Background

San Francisco Baykeeper brought a citizen suit under the Clean Water Act against the Cities of Sunnyvale and Mountain View. Baykeeper alleges that the Cities violated two provisions of their National Pollutant Discharge Elimination System permit: Discharge Prohibition A.1, concerning effective prohibition of non-stormwater discharges into storm-drain systems and watercourses, and Receiving Water Limitation B.2, concerning causing or contributing to violations of applicable water-quality standards.

The final pretrial order resolved several disputes before a bench trial, including motions in limine, which are requests to restrict evidence or argument at trial; motions to amend pleadings; a standing dispute; and the Cities’ objection to late-disclosed witnesses.

Motions in Limine

The Cities’ Motion in Limine No. 1 sought to exclude evidence about the Sunnyvale East Channel and Guadalupe Slough because the court had previously held that Baykeeper lacked standing to raise claims concerning those waterbodies. The court found the evidence relevant to whether pollution moved downstream into waterbodies where Baykeeper did have standing. The court did not decide at this stage whether the Cities could face liability for violations in the East Channel or Slough and directed the parties to address that issue in posttrial briefing. The court DENIED the Cities’ Motion in Limine No. 1.

The Cities’ Motion in Limine No. 2 sought to exclude evidence about B.2 violations after Baykeeper’s February 2019 water-quality sampling. The court rejected the Cities’ arguments that the later evidence was insufficient as a matter of law or irrelevant because the 2022 Permit was not itself at issue. The court held that those arguments concerned the weight and sufficiency of the evidence, not its admissibility before trial. The court DENIED the Cities’ Motion in Limine No. 2.

The Cities’ Motion in Limine No. 3 sought to exclude evidence about non-exfiltration sources of non-stormwater, including outdoor defecation, pet waste, and trash-receptacle leachate. The court found that the Cities had not identified specific undisclosed evidence or witnesses and that Baykeeper had disclosed this theory when it amended its complaints in 2022. The court also stated that experts’ trial testimony is limited to their reports, while objections that testimony exceeds a report are better addressed through cross-examination or a later motion to strike. The court DENIED the Cities’ Motion in Limine No. 3 without prejudice to specific objections at trial.

The Cities’ Motion in Limine No. 4 sought to exclude the opinions of Baykeeper’s economic expert, Jonathan Shefftz, about benefits the Cities allegedly gained by not complying with their permits. The court held that the Cities’ objections concerned the merits, the appropriate injunctive relief, or the weight of the testimony rather than admissibility. The court DENIED the Cities’ Motion in Limine No. 4.

Baykeeper’s Motion in Limine No. 1 challenged supplemental opinions by the Cities’ economic expert, Dr. Mark Berkman. The court held that opinions based on new information outside the narrowly reopened discovery— including new Census data and certain new financial data—were outside the permitted scope and had to be excluded. Opinions concerning the Cities’ request to redesignate certain waters from REC-1, meaning water-contact recreation, to REC-2, meaning non-water-contact recreation, were admissible because that request appeared in one of the Cities’ reports. The court found Baykeeper’s reliability objections went to the weight of the opinions, not admissibility. The court GRANTED IN PART and DENIED IN PART Baykeeper’s Motion in Limine No. 1.

Baykeeper’s Motion in Limine No. 2 challenged supplemental opinions by the Cities’ stormwater-management expert, Brandon Steets. The court deferred objections concerning legal conclusions until trial, excluded Steets’ Supplemental Opinion 5 because it exceeded the scope of reopened discovery, and permitted Steets to testify about the remainder of his supplemental opinions. The court GRANTED IN PART and DENIED IN PART Baykeeper’s Motion in Limine No. 2.

Baykeeper’s Motion in Limine No. 3 sought to exclude all evidence and argument concerning the Cities’ equitable defenses. The court concluded that equitable defenses are allowed in Clean Water Act citizen suits, although the Cities face a high burden to defeat Baykeeper’s request for injunctive relief. The court DENIED Baykeeper’s Motion in Limine No. 3.

Motions to Amend

Baykeeper sought to amend its complaints to add claims under the 2022 Permit for violations of Prohibition A.1 and Limitation B.2 and to add a claim under Provision C.14 concerning monitoring and reporting. Because the deadline to amend had passed, Baykeeper had to show good cause, which primarily depends on diligence.

The court found Baykeeper was not diligent in seeking to add the A.1 and B.2 claims under the 2022 Permit. Baykeeper had known about that permit for more than three years and had been aware of the Cities’ position concerning the permit for about a year, but waited until two weeks before trial to seek amendment. The court also denied leave to add the C.14 claim. Even assuming Baykeeper had good cause based on a report that became available in March 2025, amendment would be futile because Baykeeper had not given the Cities the required 60-day notice of intent to sue concerning monitoring and reporting violations under the new permit. The court DENIED Baykeeper’s motion to amend in its entirety.

The Cities sought to amend their answers to add due-process defenses based on alleged vagueness of the permit provisions and an alleged denial of judicial review. The court found no good cause for the late vagueness defense because the Cities could have raised it earlier. The court found good cause for the judicial-review defense because a 2025 Supreme Court decision had changed the relevant legal landscape and the Cities acted promptly afterward. However, the court concluded that adding that defense would be futile. It therefore DENIED the Cities’ motion for leave to amend.

Scope of Trial

The court held that Baykeeper’s complaints encompass injunctive relief for violations of the 2022 Permit because the conduct being challenged remained the same and the complaints gave notice that Baykeeper sought forward-looking relief. The complaints did not, however, give the Cities adequate notice that they could face civil penalties for violations of the 2022 Permit. The court emphasized that this conclusion was based on the complaints’ lack of notice under Federal Rule of Civil Procedure 8(a)(3), not on the Clean Water Act’s 60-day notice provision. The trial will therefore be limited to civil penalties for violations of the 2015 Permit and injunctive relief for violations of the 2022 Permit.

Standing

The Cities questioned whether Baykeeper had standing to allege violations of both REC-1 and REC-2 water-quality standards. The court held that Baykeeper has standing to raise both. For REC-1, Baykeeper’s members testified that they avoided water contact because they feared pollution, which the court found sufficiently connected their injuries to REC-1 violations. For REC-2, the court relied on its prior finding that Baykeeper’s members’ aesthetic interests were harmed. The court therefore reaffirmed that Baykeeper has standing to raise violations of both standards.

Late-Disclosed Witnesses

The Cities objected to three laboratory witnesses whom Baykeeper had not specifically named in its initial disclosures. The court agreed that Baykeeper’s disclosure was inadequate under Rule 26 because producing test results and referring generally to documents did not identify the individuals likely to have discoverable information. But the court found the failure harmless under Rule 37 because Baykeeper intended to use the witnesses only to authenticate water-quality testing results, and the Cities had not questioned the results’ authenticity. The court OVERRULED the Cities’ objections and limited the witnesses’ direct testimony to authentication, without limiting the Cities’ cross-examination.

Disposition

The court ruled as follows:

- The Cities’ Motion in Limine No. 1 was DENIED. - The Cities’ Motion in Limine No. 2 was DENIED. - The Cities’ Motion in Limine No. 3 was DENIED without prejudice. - The Cities’ Motion in Limine No. 4 was DENIED. - Baykeeper’s Motion in Limine No. 1 was GRANTED IN PART and DENIED IN PART. - Baykeeper’s Motion in Limine No. 2 was GRANTED IN PART and DENIED IN PART. - Baykeeper’s Motion in Limine No. 3 was DENIED. - Baykeeper’s Motion to Amend was DENIED. - The Cities’ Motion to Amend was DENIED. - Baykeeper had standing to raise violations of both REC-1 and REC-2 water-quality standards. - The Cities’ objections to the late-disclosed witnesses were OVERRULED.

Judge Edward J. Davila signed the order on June 6, 2025.