River Heights committee conditionally approves Cottonwood Bend subdivision pending stormwater agreements and plat edits

The River Heights Design Review Committee conditionally approved the Cottonwood Bend minor subdivision final plat and construction drawings at its Aug. 13, 2025 meeting, provided a stormwater maintenance agreement is executed and several plat edits are made.

The committee made the approval contingent on three primary items: (1) a stormwater maintenance agreement acceptable to River Heights City, (2) removal of the word "City Council" from the plat signature block and other wording changes on note 6 about sanitary sewer dedication, and (3) a legal review and sign-off of existing irrigation agreements and how they relate to the state's MS4 (municipal separate storm sewer system) permitting and jurisdiction. The committee also required a new note on the plat explicitly prohibiting basements in the development and confirmation that tracer wire for the sewer mainline is called out on the construction drawings.

Why it matters: the subdivision discharges to an outfall that lies outside River Heights' MS4 boundary, in territory controlled by adjacent jurisdictions and private entities. Committee members and staff said the legal status of existing irrigation agreements and the MS4 permit language could affect what approvals are required and whether additional agreements with the Cobblestone HOA and Providence City will be necessary before final recording. The committee's conditional approval allows the development to proceed through the DRC process while those cross-jurisdictional items are resolved.

Major outcomes and required changes

- Conditional approval: The committee voted to approve the Cottonwood Bend final plat and construction documents on the condition that a stormwater maintenance agreement acceptable to River Heights City is executed before recording; the city attorney must review the irrigation agreements and advise on how the existing agreements interact with state MS4 requirements. The motion, as recorded in the meeting, included the requirement that the attorney review the irrigation agreements and provide legal approval of the standing of the stormwater discharge system. The approval was taken by voice vote and recorded as all present in favor.

- Plat edits: The committee directed the applicant to remove the phrase "accepted by the River Heights City Council" from the plat signature block and instead use wording such as "approved and accepted by River Heights City." Committee members also directed striking the second sentence of note 6 that referenced sanitary sewer dedication wording; the first sentence should state that related infrastructure is dedicated to River Heights City.

- Stormwater jurisdiction and agreements: Committee members and staff discussed that the subdivision's outfall ultimately discharges through ditches and infrastructure outside River Heights' MS4 area. Committee members said an agreement with the Cobblestone HOA is the practical first step; Providence City, as the MS4 permit holder for the receiving system, will need to be involved after the Cobblestone agreement is in place. The committee required that the city attorney review the irrigation agreement(s) already in place and confirm whether those documents and any new agreement with Cobblestone and Providence City satisfy state MS4 permit obligations.

- Basements and construction details: Because of locally high groundwater in parts of the area, the committee added a note to the plat that basements are not allowed in the development. Staff also confirmed that the construction drawings must clearly call out tracer wire for the sewer mainline (sheet 501 was cited as the location of the tracer-wire detail).

Next steps

The committee asked the applicant to deliver final vellums with the requested redlines. Staff will circulate the irrigation agreement and the draft stormwater maintenance agreement to the city attorney for review. Once the required plat edits and the stormwater maintenance agreement are completed and the attorney and staff approve the legal standing of the irrigation/stormwater arrangements, the mayor and the committee chair will sign the vellums and the plat may be recorded.

Context and technical points raised in discussion

Committee members and staff repeatedly noted that the site historically drained to the same ditch and that the project includes a detention pond sized to hold post-development runoff to pre-development volumes. Staff said that while detention reduces peak flows, the state's MS4 permit and local jurisdictional boundaries determine whether River Heights or Providence City (the downstream MS4 permit holder) must formally consent to the outfall. Members warned that Cobblestone could still impose conditions, and Providence City could require a separate agreement once Cobblestone's position is known. Committee members described the issue as important for future development in the same drainage area but not a reason to indefinitely delay the current minor subdivision application.

Ending

The committee approved the conditional motion and the amendment banning basements by voice vote. Staff and the applicant will complete the plat edits, secure the stormwater maintenance agreement, and obtain attorney sign-off on the irrigation/MS4 issues before final signatures and plat recording.