# Presentation: 024844

## New England SPARROW Water-Quality Nutrient Models

**New England SPARROW Water-Quality Nutrient Models**

- Richard Moore, Craig Johnston, and Keith RobinsonUSGS, NH/VT District, Pembroke, NH

## Today’s Presentation

-  What is SPARROW
-  SPARROW model results for        New England
-  Introduce potential uses of SPARROW data

## SPARROW (Spatially Referenced 

*Regressions On Watershed Attributes)*
-  Described in Smith and others, *Water Resources **	**Research,* 33(12): 2781-2798
-  An empirical approach relating observed water-	quality data (TN and TP loads) to upstream 	watershed characteristics in a GIS framework

## SPARROW (Spatially Referenced 

*Regressions On Watershed Attributes)*
-   Incorporates variables to simulate in-stream 	processes
-   Incorporates only statistically significant variables.

## Slide 5

## Hydrologic Network – the Back-bone of SPARROW

- Upstream monitoring station

- Point source

- Reach segment

- Reach segment contributing area

- Downstream monitoring station

**Hydrologic Network – the Back-bone of SPARROW**

## Purpose of the New England Model is to support major water-quality management activities 

-      Nutrient criteria development - Ranges in nutrient 	levels in rivers and streams throughout the region
-      TMDL program - Identification of factors (sources 	and watershed characteristics) affecting nutrient 	levels
-      Coastal Water Assessments - Transport of nutrients 	by rivers (especially interstate) 	to coastal waters

## Design of the New England SPARROW 	Model

-    Focus on Total Nitrogen and Total 	Phosphorus loads
-    Model for the mid-1990s time period
-    Improve on national model for more spatial 	detail and using local data sets
-    Collaboration with EPA and NEIWPCC

## Status of the New England SPARROW Modeling Effort

-  Final models calibrated and applied to 	region
-  Final report is published
-  EPA/NEIWPCC conducting external 	review

## New England Model

**New England Model**
**Watersheds and Streams**
**Reaches**
** ****Based on the National **
**   ****Hydrography**
**   ****Data Set (NHD)**
** ****Approx 42,000 in model**
** ****Average 1.7 mi****2**** in size**
** ****Corrected to NRCS 12-digit ****    watersheds**
** ****Hydrologically connected**

##     Generation of  NHD Reach Catchments Using                    a Hydrologically-Conditioned DEM  Incorporating: 

-     Generation of  NHD Reach Catchments Using                    a Hydrologically-Conditioned DEM  Incorporating:

- National
- Hydrography
- Dataset (NHD)

- Watershed
- Boundary
- Dataset (WBD)

- National
- Elevation
- Dataset (NED)

- NE SPARROW developed a process to create
- a DEM which recognizes these three datasets

## Slide 12

## Nutrient Water-Quality Monitoring Sites used in SPARROW Model

## Nutrient (Dependent) Data to be Used in the Model

-  Collected data from USGS, STORET, States, research studies 	during the 1980-2000 time period.
-  Calculated discharge/nutrient relation to predict nutrient loads 	during all conditions of a hydrograph using the USGS 	Estimator Program. 		67 TP and 65 TN sites
-  Mean annual loads for years of water-quality and streamflow 	data

## Nutrient Sources

- Point Source

- Atmospheric deposition of
- nitrogen ( Ollinger 1992)

- National Land Cover
- Dataset 1992
-   - Agriculture
-   - Developed
-   - Forest

- Soil permeability –
- STATSGO

- Mean annual stream-flow
- Reservoir detention

- Processes

- Land to water delivery

- In-stream loss

- NE SPARROW Model Input

## Model Calibration Results for the 

**New England SPARROW Nitrogen Model**
- R-squared = .95, MSE = 0.16
**Variable                          Bootstrap        Standard**
**                                               ****model ****	****   error of          p-value**
**SOURCES                     coefficient       coefficient**
**                                                                                                      **
**Municipal wastewater-**
**  ****treatment facilities****	****       ****	****1.13                0.36    ****	****<.005**
**  **
**Atmospheric deposition    ****	****.36                  .07 ****	****<.005**
**  **
**Cultivated agricultural **
**    ****land  (kg/km****2****/y)  ****	****	****910               362 ****	****	**** .005**
**Developed urban **
**    ****land   (kg/km****2****/y)**** ****	****	****988                385**** ****	**** .010**
**    **

## Model Calibration Results for the 

**New England SPARROW Nitrogen Model (cont.)**
- R-squared = .95, MSE = 0.16
**Variable                 Bootstrap       Standard **
**                                      ****model ****	****       error of         p-value **
**       ****	****	****           ****coefficient     coefficient**
**                                                                                                      **
**Delivery variable:**
**  ****Natural Log of **
**  ****Soil Permeability            0.36                0.14 ****	****   <.005**
**  **
**Decay Variable:**
** ****Stream decay****	****          ****.71                 .52    ****	****    .065**
** ****for streams  <= 100 cfs**
**(per day)**

## Model Calibration Results for the 

**New England SPARROW Phosphorus Model**
- R-squared = .94, MSE = 0.23
**Variable                          Bootstrap        Standard**
**                                               ****model ****	****   error of          p-value**
**SOURCES                     coefficient       coefficient**
**                                                                                                      **
**Municipal wastewater-**
**  ****treatment facilities****	****       ****	****1.28                0.22    ****	****<.005**
**  ****and pulp and paper**
**Forested Land****	****    ****	****12.7                  4.1 ****	****<.005**
**    ****(kg/km****2****/y)**
**Cultivated agricultural **
**    ****land  (kg/km****2****/y)  ****	****	****110                 27.5 ****	****<.005**
**Developed urban **
**    ****land   (kg/km****2****/y)**** ****	****	****37.8                14.3**** ****	**** .005**
**    **

## Model Calibration Results for the 

**New England SPARROW Phosphorus Model (cont.)**
- R-squared = .94, MSE = 0.23
**Variable                 Bootstrap       Standard **
**                                      ****model ****	****       error of         p-value **
**       ****	****	****           ****coefficient     coefficient**
**                                                                                                      **
**Decay variables:**
**Reservoir decay for small **
**lakes and reservoirs         105                59.7 ****	****    .04**
**(****<= 10 km****2****)**   **(m/y)**
**  **
**Decay Variable:**
** ****Stream decay****	****          ****.42                 .41    ****	****    .125**
** ****for streams  <= 100 cfs**
**(per day)**

## =

- SPARROW Model Results:

**Predicted Total Nitrogen **
**Catchment Yield**

**Contributions to Total Nitrogen**
**from each source**

**Atmospheric**

**Urban**

**Agriculture**

**Point Source**

**=**

**+**

**+**

**+**

## Atmospheric Deposition of Nitrogen

## Slide 22

## Slide 23

## SPARROW Model Results: 

**Agricultural Land**

## SPARROW Model Results: 

**  ****Forest**

**Urban**

**Point Source**

**Agricultural**

**Primary Sources of **
**Phosphorus**

**Primary Sources of **
**Nitrogen**

**Point Source**

**Urban**

**Atmospheric**

**Agricultural**

- SPARROW Model Results:
- Identifying Primary Sources  of Nutrients

## Utility of New England SPARROW Model Results for Nitrogen Loading Assessments

**Utility of New England SPARROW Model Results for Nitrogen Loading Assessments**
** ****An Example from the Connecticut River Basin**

## Estimated Mean Annual concentration of (A) Nitrogen and (B) phosphorus.

**Estimated Mean Annual concentration of (A) Nitrogen and (B) phosphorus****.**

## Assessing Nutrient Loadings to Coastal Waters

**Assessing Nutrient Loadings to Coastal Waters**

## Model Strengths (cont.)

*SPARROW has been recognized by the National Academy of Sciences and National Research Council as a suggested regional assessment tool, specifically for TMDLs*

## THE END