MMSK Stormwater Quality Improvement and Stream Restoration Project (DRAFT)

Montessori Middle School of Kentucky
The MMSK Project will:
Reduce stormwater runoff quantity.
Improve water quality in South Elkhorn watershed.
Educate students and public about storm water quality, and involve them in practical solutions to improve it.

Background: The stream on MMSK property drains 245 acres (or over 10,000,000 square feet) of commercial (90%) and residential (10%) areas. Except for the MMSK property, the watershed is 100% developed, with a land cover of over 60% impervious area.
The MMSK property is the most upstream portion of the "natural" stream (i.e. not in a pipe). All of the runoff from upstream enters the property through three culvert locations. Most of the watershed (inside New Circle) was developed prior to the requirements of stormwater detention or water quality treatment. As such the runoff is very flashy, peaks quickly, and carries a large load of pollutants from road and parking lot runoff.

Water Quality Data: The water has been sampled for 5 to 6 years.

MMSK purchased the 12 acre property in 2006, with the goal of utilizing the stream as the focal point for their environmentally sustainable education (K-8) campus.

MMSK Project Summary:
Utilize rain gardens to capture and treat on-site runoff.
Utilize constructed wetlands to capture pollutants from off-site runoff.
Restore stream by lowering floodplain and banks to reduce sediment from bank erosion and increase stormwater detention/retention capacity.
Install wetlands in new, lower floodplain to retain runoff and treat pollutants.
Install organic (carbon) filter/aquifer in stream bed to treat pollutants in stream baseflow (nutrients, especially nitrogen)
Use 10,000 gallon underground infiltration chamber system to recharge groundwater from relatively clean roof runoff.
Water Quality Monitoring to determine BMP effectiveness and treatment efficiency.

Schedule for Structural BMP Implementation:
FY 2011: Design and WQ Monitoring (Pre-construction)
FY 2012: Construction
FY2013: WQ Monitoring (Post-construction)

Project Criteria:
1. Project Location/Impact:
a. Located in the South Elkhorn watershed.
b. The MMSK facility is a developed Class B parcel. The upstream watershed is 100% developed.
c. The MMSK project targets the following pollutants:
i. Nutrients: Nitrogen and phosphorus (sources: fertilizer, bird and pet feces, etc.)

MMSK Stormwater Quality Improvement and Stream Restoration Project (DRAFT)
Montessori Middle School of Kentucky
ii. Metals, salts, inorganic and organic chemicals (sources: commercial truck and vehicle parking areas, local roads, New Circle Road)
iii. Organic Enrichment: BOD, organic material (untreated sewage, leaves, grass, etc.)
iv. Sediment, TSS: (sources: bank erosion of channel on property and downstream channel, upstream sediment disturbing activities)
d. The project stream flows through Stonewall Estates, which contains structures that have experienced flooding due to the complicated karst nature, and then into South Elkhorn.
e. Will treat stormwater runoff and pollutants from 245 acres (or over 10,000,000 square feet) of commercial (90%) and residential (10%) areas.
2. Project Type:
a. Proposed Structural BMP’s:
i. Rain garden (bioretention system): dual water quality/water quantity BMP
ii. Constructed wetlands: dual water quality/water quantity BMP
iii. Water quality trash collection manhole: water quality BMP
iv. Underground infiltration chamber system: dual water quality/water quantity BMP
v. Stream restoration
1. Floodplain wetlands: dual water quality/water quantity BMP
2. Lower and wider floodplain: dual water quality/water quantity BMP
3. Organic (carbon) filter/aquifer in stream bed: water quality BMP
b. Educational Opportunities:
i. MMSK student and teacher education of stormwater pollution and treatment.
ii. Community walking trail around and through riparian area with environmental signage.
iii. Kentucky Transportation Cabinet will use as a demonstration project.
iv. MMSK is a partner project with the UK Tracy Farmer Institute for Sustainability and the Environment (TFISE) and their Outdoor Environmental Learning Centers (OELC) program. Partnering schools include:
1. Clays Mill Elementary (FCPS)
2. Millcreek Elementary(FCPS)
v. UK TFISE will host tours with Bluegrass Rain Garden Alliance, UK Colleges of Engineering and Agriculture, LFUCG, KY Natural Channel Design Working Group, KY Wetlands Working Group, etc.
3. Project Design Innovation:
a. The proposed structural BMP’s have been proven to work in the previously constructed Mill Creek Wetland and Stream Restoration Project, and other projects throughout the state.
b. Innovative design components include:
i. Treating and removing pollutants from stream baseflow with organic (carbon) filter/aquifer.
ii. Utilizing low floodplain with wetlands to remove pollutants from stormwater runoff.
iii. Creating outdoor classroom for school use in conjunction with stormwater quality structural BMP.

MMSK Stormwater Quality Improvement and Stream Restoration Project (DRAFT)
Montessori Middle School of Kentucky
iv. Incorporating environmental walking trail with signage describing water quality BMP’s.
v. Retrofitting existing detention basin into constructed wetland while maintaining required detention storage.
c. The project is a retrofit of existing stormwater systems. The headwall at the end of the storm sewer from Ark Royal Way is failing (see photo) and needs to be replaced. The existing detention basin on site will be retrofitted with a constructed wetland. The existing school roof runoff will be captured in an underground infiltration chamber system.
d. The project education is tied to the UK TFISE OELC, which will host on-site tours and workshops for professionals and the public, develop student water quality curriculum, hold teacher professional development courses, and student involvement in the construction and planting.
4. Project Success Measures:
a. The design/build team has designed and permitted a similar project at Millcreek Elementary utilizing rain gardens, constructed wetlands, and stream restoration. The Mill Creek project was a winner of the Kentucky Environmental Quality Commission 2010 Earth Day Award.
b. MMSK is willing to grant a conservation or similar easement to LFUCG for perpetuity to protect the structural BMP’s funded by the WQMF Incentive Grant.
5. Project Sustainability:
a. MMSK takes great pride in their campus as can be shown by their work to remove invasive honeysuckle, plant native trees, clean up trash and debris, etc. They will maintain the proposed BMP’s using more than a minimum industry standard Operations and Maintenance Plan.
b. The Montessori philosophy encourages students to participate in a hands-on fashion. Students and teachers alike care for their campus and will continue to maintain the structural BMP’s installed as part of this project.
c. MMSK will continue to maintain their facility. MMSK does ask that LFUCG clean out the WQ Trash Collection Manhole on at least an annual basis because they do not have the capabilities to do so in a confined space.
d. All project elements can and will be easily accessed for maintenance and monitoring. The WQ Trash Collection Manhole can be accessed by LFUCG vacuum truck from Ark Royal Way to the north.