Flood Information
The Town of Ross is prone to flooding. Residents, both in and out of flood zones, should be prepared for flood emergencies. Areas near Corte Madera and Ross creeks are most likely to flood during storms. These areas include land west of Sir Francis Drake Boulevard, Shady Lane, Ross Common, Poplar, Redwood and areas of Fernhill and Bolinas Avenue. Ross has experienced three 100-year storms in the past decades (1982, 1986 and 2006). Engineers use the term “100-year storm” to describe a storm that has a 1% chance of occurring in any given year (not a storm that occurs only once in 100 years). Even less severe storms cause Corte Madera and Ross Creeks to rise and local flooding problems.
Ross Valley Flood Protection & Watershed Program:
http://www.rossvalleywatershed.org
Map of Local Flood Hazards
Flood Insurance Rate Map for the Town of Ross
General flood, flood insurance and flood safety information is available from FEMA:
http://www.fema.gov
Real Time Corte Madera Creek Gage Data
The Marin County Flood Control and Water Conservation District maintains a stream gaging station in Corte Madera Creek, near Town Hall, to provide real-time data on the level of the creek.
Corte Madera Creek Stage Monitor
Flood Safety
Do not walk through flowing water. Drowning is the number one cause of flood deaths. Currents can be deceptive, only six inches of moving water can knock you off your feet. If you walk in standing water, use a pole or stick to ensure that the ground is still there.
Do not drive through a flooded area. More people drown in their cars than anywhere else. Don’t drive around road barriers; the road or bridge may be washed out.
Stay away from power lines and electrical wires. The number two flood killer after drowning is electrocution. Electrical current can travel through water. Report downed power lines to the PG&E.
Have your electricity turned off. Some appliances, such as television sets, keep electrical charges even after they have been unplugged. Don’t use appliances or motors that have gotten wet unless they have been taken apart, cleaned, and dried.
Look before you step. After a flood, the ground and floors are covered with debris including broken bottles and nails. Floors and stairs that have been covered with mud can be very slippery.
Be alert for gas leaks. Use a flashlight to inspect for damage. Don’t smoke or use candles, lanterns, or open flames unless you know the gas has been turned off and the area has been ventilated.
Office of Emergency Services: http://www.oes.ca.gov
Be prepared for 72 hours: http://www.72hours.org
Disaster preparedness: http://www.ready.gov/
Drainage System Maintenance
The watercourses and drainage ways in Town may be a major cause of flooding when blocked. Maintaining the flow capacity in creeks, watercourses and drainage ways in Town requires cooperation and assistance to prevent flooding and bank erosion. Please be sure that any watercourse or drainage way on or adjacent to your site is clean and clear of all obstructions and debris. The water should be able to flow freely under fences.
Do not dump or throw anything into ditches or streams: A plugged channel cannot carry water, and when it rains, the excess water must go somewhere. Trash and vegetation dumped into a stream degrades water quality of both the stream itself and its receiving waters, and every piece of trash contributes to flooding.
Remove debris, trash, loose branches and vegetation: Keep banks clear of brush and debris to help maintain an unobstructed flow of water in stream channels. Do not, however, remove vegetation that is actively growing on a stream bank. Streamside vegetation is tightly regulated by local, state and federal regulations. Before undertaking any removal of streamside vegetation, contact the Town. Please report any observations of the clearing of vegetation or trees on stream banks to the Town.
Flood Warning System
The Town uses different methods of alerting residents of floods. For decades, an air horn on top of the fire house has served that purpose. In 2008, that horn will be replaced with a new electric siren system. The system will be tested each Saturday at noon. If the siren is sounded during the winter months, residents should be alert for a flood emergency. If heard during the summer months residents should be alert for a fire. In either case, the sound of the signal means to be alert for information how to react. Sources of information include: local television stations, local AM radio stations (KCBS AM 740), the Telephone Emergency Notification System, or the public address system from a passing police car.The Telephone Emergency Notification System (TENS) is a subscriber-based system used by the Town of Ross to send recorded emergency announcements to residents via telephone. Residents may subscribe to the system by completing an application form available at Town Hall, the Public Safety Building or by downloading the form here.
In addition, the Town sends flood warnings and information to addresses in the Town email list. Contact Linda Lopez via Email to be included on the Town email list.
Property Protection Measures
The Town provides sandbags free of charge to residents each winter. The self-serve sandbag stations are located at the entrance to Natalie Coffin Greene Park and at the Town corporation yard behind the fire station. Residents who may need sandbags should pick them up well in advance of heavy rains and should not wait until flooding begins. This is self-service, so please bring a shovel to fill your bags.
Practical and cost-effective methods for reducing or eliminating the risk of flooding are available to property owners whose homes have experienced damage from flooding in the past, or may experience damage in the future. Such techniques include elevation of the home, flood-proofing, and protecting utilities. For further information, contact the Building and Planning Departments and the Federal Emergency Management Agency.
The following publications are available at the FEMA web site:
Above the Flood: Elevating your Flood Prone House
Elevated Residential Structures
Floodproofing for Nonresidential Structures
Natural and beneficial functions of floodplains
Floodplains are a natural component of the environment. Understanding and protecting the natural functions of floodplains helps reduce flood damage and protect resources. When flooding spreads out across the floodplain, its energy is dissipated, which results in lower flood flows downstream, reduced erosion of the streambank and channel, deposition of sediments higher in the watershed and improved groundwater recharge. Floodplains are scenic, valued wildlife habitat. Poorly planned development in floodplains can lead to streambank erosion, loss of valuable property, increased risk of flooding to downstream properties and degradation of water quality.
Building in the Floodplain
Flood Damage Prevention Ordinance
Work within the flood hazard areas must comply with the Town Flood Damage Prevention Ordinance. Any work within 25 feet of a creek or watercourse (even a seasonal watercourse) requires design review. So, always check with the Building and Planning Departments before you build on, alter, re-grade, or fill on your property. A permit may be needed to ensure that projects do not cause problems on other properties.
Floodplain management requirements apply to new construction and to substantial improvements. “Substantial improvement” is any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the start of construction of the improvement. This term includes structures which have incurred “substantial damage”. The term does not, however, include either:
1) Any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications and which are the minimum necessary to assure safe living conditions or
2) Any alterations of a historic structure, provided that the alteration will not preclude the structure’s continued designation as a historic structure.
If you see building or filling without a Town permit posted, please contact the Building Department.
Flood Insurance and Flood Zone Information
The Town of Ross participates in the National Flood Insurance Program (NFIP), which makes federally backed flood insurance available for all eligible buildings, whether they are in a floodplain or not. Flood insurance covers direct losses caused by surface flooding, including a creek flowing over its banks and local drainage problems.
As a public service, the Town of Ross will provide you with the following information upon request:
Whether a property is in or out of the Flood Hazard Area (FHA) as shown on the current Town Flood Insurance Rate Map (FIRM).
Additional flood insurance data for a site, such as the FIRM zone and the base flood elevation or depth, if shown on the FIRM.
We have a handout on the flood insurance purchase requirement that can help people who need a mortgage or loan for a property in the Special Flood Hazard Area. Click About the mandatory purchase of flood insurance to download the handout.
The Town of Ross maintains elevation certificates for review at our office and on this site.
We update the Flood Insurance Rate Maps as needed when revisions are made to the maps.
If you would like additional information, please contact the Building Department. There is no charge for this service.
FEMA Elevation Certificate Form
Town of Ross Elevation Certificates:
Allen Avenue 24
Allen Lane 5
Bolinas Avenue 55
Bolinas Avenue 73
Brookwood 17
Dewitt Drive 2
Fernhill 2
Poplar 55
Poplar 57
Poplar 63
Poplar 65
Redwood Drive 21
Redwood Drive 27
Redwood Drive 37
Redwood Drive 44
Redwood Drive 45
Redwood Drive 47
Shady Lane 20
Shady Lane 64
Shady Lane 72
Shady Lane 83
Shady Lane 90
Shady Lane 96
Sir Francis Drake 15
Sir Francis Drake 26
Sir Francis Drake 29
Sir Francis Drake 65
Sir Francis Drake 79