Check with below code.

protected void Page_Load(object sender, EventArgs e)
{
    CreateScriptTable("master", "Water", ConfigurationManager.ConnectionStrings[1].ConnectionString);
    CreateScriptDataBase("Water", ConfigurationManager.ConnectionStrings[1].ConnectionString);
}

public void CreateScriptTable(string dataBaseName, string tableName, string connectionString)
{
    try
    {
        if (!Directory.Exists(Server.MapPath("~/backup/")))
        {
            Directory.CreateDirectory(Server.MapPath("~/backup/"));
        }
        SqlConnection con = new SqlConnection(connectionString);
        ServerConnection serverConnection = new ServerConnection(con);
        Server server = new Server(serverConnection);
        Database database = server.Databases["" + dataBaseName + ""];
        if (database != null)
        {
            Scripter scripter = new Scripter(server);
            scripter.Options.ScriptData = true;
            scripter.Options.ScriptSchema = true;
            scripter.Options.ScriptDrops = false;
            var sb = new System.Text.StringBuilder();
            foreach (Microsoft.SqlServer.Management.Smo.Table table in database.Tables)
            {
                if (table.Name.ToLower() == tableName.ToLower())
                {
                    sb.Append("DROP TABLE " + table.Name);
                    sb.Append(Environment.NewLine);
                    foreach (string s in scripter.EnumScript(new Urn[] { table.Urn }))
                    {
                        sb.Append(s);
                        sb.Append(Environment.NewLine);
                    }
                    string folder = Server.MapPath("~/backup/");
                    string filename = folder + tableName + ".sql";
                    System.IO.StreamWriter fs = System.IO.File.CreateText(filename);
                    fs.Write(sb);
                    fs.Close();
                }
            }
        }
    }
    catch (Exception ex)
    {
        string message = string.Format("Message: {0}\\n\\n", ex.Message);
        message += string.Format("StackTrace: {0}\\n\\n", ex.StackTrace.Replace(Environment.NewLine, string.Empty));
        message += string.Format("Source: {0}\\n\\n", ex.Source.Replace(Environment.NewLine, string.Empty));
        message += string.Format("TargetSite: {0}", ex.TargetSite.ToString().Replace(Environment.NewLine, string.Empty));
        ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert(\"" + message + "\");", true);
    }
}

public void CreateScriptDataBase(string dataBaseName, string connectionString)
{
    try
    {
        if (!Directory.Exists(Server.MapPath("~/backup/")))
        {
            Directory.CreateDirectory(Server.MapPath("~/backup/"));
        }
        SqlConnection con = new SqlConnection(connectionString);
        ServerConnection serverConnection = new ServerConnection(con);
        Server server = new Server(serverConnection);
        Database database = server.Databases["" + dataBaseName + ""];
        if (database != null)
        {
            Scripter scripter = new Scripter(server);
            scripter.Options.ScriptData = true;
            scripter.Options.ScriptSchema = true;
            scripter.Options.ScriptDrops = false;
            var sb = new System.Text.StringBuilder();
            foreach (Microsoft.SqlServer.Management.Smo.Table table in database.Tables)
            {
                sb.Append("DROP TABLE " + table.Name);
                sb.Append(Environment.NewLine);
                foreach (string s in scripter.EnumScript(new Urn[] { table.Urn }))
                {
                    sb.Append(s);
                    sb.Append(Environment.NewLine);
                }
                string folder = Server.MapPath("~/backup/");
                string filename = folder + dataBaseName + ".sql";
                System.IO.StreamWriter fs = System.IO.File.CreateText(filename);
                fs.Write(sb);
                fs.Close();
            }
        }
    }
    catch (Exception ex)
    {
        string message = string.Format("Message: {0}\\n\\n", ex.Message);
        message += string.Format("StackTrace: {0}\\n\\n", ex.StackTrace.Replace(Environment.NewLine, string.Empty));
        message += string.Format("Source: {0}\\n\\n", ex.Source.Replace(Environment.NewLine, string.Empty));
        message += string.Format("TargetSite: {0}", ex.TargetSite.ToString().Replace(Environment.NewLine, string.Empty));
        ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert(\"" + message + "\");", true);
    }
}