This project will increase flood protection for the Martinez Adult School campus, reduce stormwater runoff, and extend a successful riparian restoration project on this site.
This project will increase flood protection for the Martinez Adult School campus, which is located next to Alhambra Creek, and extend a successful riparian restoration project on this site.
A protective berm with a robust spillway and vegetated swale will be installed which will route creek overflows away from buildings to a parking lot configured to function as a detention basin.
The parking lot will be converted from asphalt to a pervious surface with vegetated filter strips. Storm drains will be fitted with backflow preventers.
The riparian area and floodplain of Alhambra Creek will be extended, and enhanced with additional native-plants and a self-guided nature trail.
This project can be used as an educational resource for students and as an outreach tool or demonstration project for the public.
Drinking Water Supply
Water Quality Improvement
Habitat Protection and Restoration
FLOOD PROTECTION-This project will route floodwater safely away from school buildings to a dual-use detention basin/parking lot.
STORMWATER IMPROVEMENT- LID measures including vegetated swales between buildings and and vegetated filter strips around the parking lot/detention basin will slow and filter stormwater.
INFILTRATION- Converting the school parking lot/detention basin to pervious pavement will greatly increase infiltration after floods and storm events, then gradually release the water as filtered groundwater seepage back into Alhambra Creek.
WATER QUALIITY - The swales, filter strips and infiltrated ground-water from the pervious parking lot will improve water quality after storm events by filtering hydrocarbons and other pollutants that are presently flushed directly into the creek.
HABITAT PROTECTION - The riparian zone will be expanded and enhanced with native plants. The filter strips and swales will also utilize native plants suitable for pollinators and birds.
This project will re-route flood flows safely around public school buildings. The City of Martinez planning and public works depts. will participate in analyzing and planning exit points adn routes for the floodwaters to leave the school property to minimize damage downstream.
Beyond the benefits of flood protection, runoff reduction, water quality improvement and habitat enhancement, because this project is on public school property, the project offers an opportunity to engage students in watershed education. (There is an environmentally focused high-school program at this site already.) It also offers an excellent demonstration site to do community outreach about Low Impact Development, pollution prevention, and habitat restoration.
YES, pervious pavement, vegetated filter strips and bioswales will be major components of this project.
Ecosystem Restoration, Environmental and habitat protection and improvement, Flood management, NPS pollution control, Recreation and public access, Storm water capture and management, Water quality protection and improvement, Watershed planning
CONTEXT: The Martinez Adult School campus borders Alhambra Creek for about 620 linear ft. in the lower watershed floodplain. This part of the creek is still subject to periodic flooding even after the creek channel was widened in 2005 to increase flow capacity.
In January of 2006, overflows of Alhambra Creek caused approximately one million dollars in damage to this school property. The possibility of housing developments upstream in the middle watershed would bring increased impervious surface that could intensify future flooding at this downstream site.
In April of 2012, the Martinez Unified School District(MUSD)Board of Education, voted to spend 5.2 million dollars to contruct new campus buildings at this site. As of 9/2012, preliminary concepts and designs are being developed for MUSD Board consideration to see how far that $5.2M can stretch. This is the ideal time to develop and integrate flood protection, LID measures and riparian corridor restoration into the overall building design for the new campus. Routing floodwaters through bioswales between the buildings out to the parking area/detention basin could protect this major investment in new construction.
The current parking area covers 1.4 acres, with an adjacent .5 acre paved lot. Converting this area,and possibly pedestrian walkways to pervious surface could yield between 1.4 to 2 acres of infiltration surface.
During the creek channel widening in 2005, native trout were discovered in the creek at this site. It was theorized that cooler water from groundwater seepage into the creek was creating preferable temperature conditions at this location that attracted the trout. Adding a large infiltration area could only improve conditions.
The Alhambra Watershed Council has offered to assist in developing ways to organically integrate the creek and an expanded riparian buffer zone into the campus design so that it can become an educational resource and community asset, while simultaneously increasing flood protection and improving water quality in the creek.
One aspect of this integration would be the self-guided nature trail along the edge of the riparian zone for the 620 feet of school property. This would be developed by the award-winning, environmentally focused high school program, "The New Leaf Collaborative for Sustainable Living" that has been housed at this campus since 2005. (see http://www.martinez.k12.ca.us/schools/briones/esa/)
Adult Education Campus Renovation
Martinez News-Gazette article on MUSD Board vote for New Campus construction. http://martineznewsgazette.com/index.php?option=com_content&view;=article&id;=8966:board-votes-in-favor-of-52-million-campus&catid;=46:news&Itemid;=81
This project is located on the banks of Alhambra Creek in Martinez.
The need for this project has been demonstrated by the estimated $1 million in flood damage from the 2006 New Year's Day flood.
The school district has a plan to completely renovate this campus and replace aging "portable" trailers with new buildings. If this flood protection work is not integrated into the campus renovation, the new structures will be in jeopardy of future flood damage.
This project would provide the opportunity to also integrate state-of-the-art LID and "green" stormwater practices into this campus renovation.
If this flood protection work is not integrated into the campus renovation, the new campus buildings will be in jeopardy of future flood damage, and future expense.
i. Water Supply (conservation, recycled water, groundwater recharge, surface storage, etc.)
Converting the large asphalt parking lot to pervious pavement will allow for groundwater recharge, that may also benefit nearby Alhambra Creek.
ii. Water Quality
iii. Flood and Stormwater Management
Flood water will be safely re-routed and stormwater will be both filtered and infiltrated.
iv. Resource Stewardship (watershed management, habitat protection and restoration, recreation, open space, etc.)
The flood plain and riparian habitat will be extended, providing habitat enhancement, but the addition of a self-guided nature trail and possible education programs will promote community watershed education and improved stewardship.
The Martinez school district includes disadvantaged communities, and students from this campus reside in these disadvantaged communities. This project has the opportunity to include watershed education and outreach to the members of these communities who attend school at this campus, or even at other campuses, depending on the type of education and outreach that is developed.
Increases Water Supply Reliability
Advances/ Expands Conjunctive Management of Multiple Water Supply Sources
Increases Water Use and/or Reuse Efficiency
Provides Additional Water Supply
Promotes Water Quality Protection
Reduces Water Demand
Advances/Expands Water Recycling
Promotes Urban Runoff Reuse
Addresses Sea Level Rise
Addresses other Anticipated Climate Change Impact (e.g. through water management system modifications)
Improves Flood Control (e.g. through wetlands restoration, management, protection)