Three things you can do
Three things you can do today. Then who is responsible for what, and how to reach them. Where we have not checked something, we say so instead of guessing.
01 · What you can do now
None of them needs an appointment. Each one leaves something with a date on it. Who to call is next.
The bulletin board is the one place on this site that keeps what you write. A dated account of water at a named corner is worth something later; remembered in a meeting three years on, it is not. Neighbors read it, and it stays yours to edit or delete.
A photo with something of known height in it (a curb, a hydrant, a door) becomes a depth in inches, in your browser, with nothing uploaded. Paired with the bay level at that minute, it is the strongest evidence you can produce, and the one kind our model cannot argue with.
An agency circulating a draft environmental document must respond in writing to substantive comments. “My street floods, here is a dated photograph, and the document does not mention it” is one. The studies page says where the documents are posted and where a comment period is announced.
02 · Who to call
If someone is in danger, call 911. Nothing below is for an emergency.
Each office is named because a document on this site says what it is responsible for. The county supervisor's numbers are here, from the county's own page. For the other offices they are not yet; until they are, each card says what the office does and what to bring.
The Army Corps describes the pond as privately owned, with a single manually operated tidal gate. Who opens and shuts it, and who to tell when water is standing behind it, this site does not know. [TODO: project team to find out who operates the gate, and add them here.]
03 · If you are measuring a photo
This is the question everything else turns on. A depth without a bay level beside it cannot be compared with anything.
Use the verified water level tab, not the prediction. Predictions are what the tide would do on astronomy alone; verified data is what the water actually did, storm surge included. Surge, the extra height a storm pushes the water up beyond the predicted tide, is the part worth capturing. This is the long-record station, and the one the photo tool asks you for.
Much closer to Richardson Bay, and useful for knowing when a high tide is coming. But it only publishes predictions: what the tide should do, not what it did. Fine for planning a trip out with a camera; not a source for a measurement.
Record which station and which you used. A depth measured against one datum and compared against another is worse than no measurement, because it looks usable. The photo tool has a field for both.
04 · This site
Every figure sorted into measured, estimated and assumed, plus the water balance written out step by step. Start here: it tells you which numbers to be wary of before you spend time on the rest. The 72 by 38 inch opening (about 19 square feet, 1.8 m²) is the one doing the most work.
344 acres, one culvert, thirty days of tide. Move the storm slider and the three measure toggles and watch what each one does to the water behind the gate. The model counts Drake & Donahue under water once the water there rises above +8.3 ft (+2.53 m) on the survey scale.
The hydrology, the terrain build and the two original standalone tools all live in the project's repository, which is not public yet. [TODO: project team to decide whether to open the repository, and link it here if so.] A site that asks to be checked is easier to take seriously when the checking is possible.
05 · Further afield
Two things you might reasonably want. One has a source we can vouch for. The other does not yet, and we say what to look for.
The Marin City Stormwater Plan, October 2025 ↗ is the authority on this drainage, and better than anything on this site: a surveyed, modeled study prepared for the Marin County Flood Control and Water Conservation District, building on a 2018 drainage study. The culvert's dimensions, the , the silted pond and the proposed pump station all come from it. Read it before you read us.
The general practice (, detention, peak-shaving) is well documented in municipal guidance and in the sponge-city literature. It is worth picking one clear introduction rather than a reading list. [TODO: project team to choose and verify one introductory source.]