1. Stormwater Corps
  2. Town Projects
  3. Norwalk

Norwalk

Project Team

Date: Summer 2024
UConn Students: Indigo Irwin, Emily Markelon, ​Sophia Steen
UConn CLEAR: David Dickson, Michael Dietz, and Chloé Zampetti ​

The Runoff Reduction Report

This report includes recommendations for green stormwater infrastructure practices at 7 sites in the city of Norwalk. Each site is displayed with an ArcGIS map of the recommended practice, detailed description of our recommendations, and an informational table. Each table shows an estimated drainage area, our recommended green infrastructure, annual gallons of runoff treated, nitrogen and phosphorus pollution reduction amounts, and the suggested size of each practice. These estimations were calculated based on the drainage area, annual rainfall estimates specific to Connecticut, and literature export values.

GSI Summary Table

The following calculations display the potential pollutant-reducing benefits if the practices identified within the report were implemented:

Site Location GSI Suggestion Drainage Area Annual Gallons Treated Annual Nitrogen Reduction (lb N/yr) Annual Phosphorous Reduction (lb P/yr? Suggested Practice Size [6in depth] (sq ft)
1
Mathews Park 
 Rain Garden 1

4,530​

119,295​

0.99​

0.13​

 736 (8in)
Rain Garden 2

3,877​

102,089​

0.85​

0.11​

 8,276
2
City Hall
 Tree Box Filters

8,146​

214,502​

1.78​

0.23​

 N/A
3
Rowayton Library​
 Rain Garden

1,045​

27,530​

0.23​

0.03​

 227
4
Cranbury Park​
 Rain Garden 1

518​

13,641​

0.11​

0.01​

 112
Rain Garden 2

211​

5,556​

0.05​

0.01​

 46
Rain Garden 3

225​

5,925​

0.05​

0.01​

 49
Rain Garden 4

6,564​

172,851​

1.44​

0.18​

 1,219 (7in)
5
Rowayton Elementary 
 Rain Garden 1

1,481​

38,999​

0.32​

0.04​

 321
Rain Garden 2

392​

10,234​

0.09​

0.01​

 85
Rain Garden 3

5,227​

137,648​

1.14​

0.15​

 1,133
6
Kendall Elementary 
 Rain Garden 1

6,316​

166,325​

1.38​

0.18​

 1,369
Rain Garden 2

653​

17,196​

0.14​

0.02​

 141
7
Senior Center 
 Tree Box Filters

8,178​

215,352​

1.79​

0.23​

 N/A

Totals

Total IC Disconnected (sq. ft.) Annual Gallons Treated Annual Nitrogen Reduction (lb. N/yr) Annual Phosphorous Reduction (lb. P/yr)
Total 47,363 1,247,143 10.36 1.34